2004 Transit of Venus by Fred Espenak Printable version by JP GODARD

Fred Espenak e-mail: mailto:[email protected] Planetary Systems Branch - Code 693 NASA's Goddard Space Flight Center, Greenbelt, Maryland 20771 USA

Permission is freely granted to reproduce this data when accompanied by an acknowledgment: "Transit Predictions by Fred Espenak, NASA/GSFC" All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Table of contents PLANETARY TRANSITS ACROSS THE SUN

3

2004 TRANSIT OF VENUS

6

OBSERVING THE TRANSIT FREQUENCY OF TRANSITS HISTORY OF TRANSITS

8 8 9

AN IMAGE OF ONE OF THE 1700 PLATES TAKEN WORLDWIDE DURING THE 1882 TRANSIT, SHOWING VENUS CROSSING THE DISK OF THE SUN. 10 COMMEMORATIVE STAMP OF THE 1769 COOK’S EXPEDITION TO TAHITI

10

PREDICTIONS FOR THE 2004 TRANSIT OF VENUS

11

INTRODUCTION TRANSIT CONTACT TIMES FOR CITIES AROUND THE WORLD

11 12

CIRCUMSTANCES FOR EUROPE

13

WORLD VISIBILITY OF 2004 TRANSIT OF VENUS

21

2004 AND 2012 TRANSITS OF VENUS

24

INTRODUCTION GEOGRAPHIC VISIBILITY OF 2004 JUNE 08 GEOGRAPHIC VISIBILITY OF 2012 JUNE 06 FREQUENCY OF TRANSITS ADDITIONAL COMMENTS

24 25 25 25 26

KEY TO CATALOGS OF TRANSITS OF VENUS

32

FOOTNOTES

34

VENUS FACT SHEET

35

ACKNOWLEDGMENTS REFERENCES (TRANSIT PREDICTIONS) REFERENCES (HISTORY OF TRANSITS) LINKS ON TRANSITS

37 38 38 39

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Planetary Transits Across the Sun

Transit of Mercury on 1973 Nov 10.

The transit or passage of a planet across the disk of the Sun may be thought of as a special kind of eclipse. As seen from Earth, only transits of the inner planets Mercury and Venus are possible. Planetary transits are far more rare than eclipses of the Sun by the Moon. On the average, there are 13 transits of Mercury each century. In comparison, transits of Venus usually occur in pairs with eight years separating the two events. However, more than a century elapses between each transit pair. The first transit ever observed was of the planet Mercury in 1631 by the French astronomer Gassendi. A transit of Venus occurred just one month later but Gassendi's attempt to observe it failed because the transit was not visible from Europe. In 1639, Jerimiah Horrocks and William Crabtree became the first to witness a transit of Venus. At the present time, all transits of Mercury fall within several days of May 08 and November 10. Since Mercury's orbit is inclined seven degrees to Earth's, it intersects the ecliptic at two points or nodes which cross the Sun each year on those dates. If Mercury passes through inferior conjunction at that time, a transit will occur. During November transits, Mercury is near perihelion and exhibits a disk only 10 arc-seconds in diameter. By comparison, the planet is near aphelion during May transits and appears 12 arc-seconds across. However, the probability of a May transit is smaller by a factor of almost two. Mercury's slower orbital motion at aphelion makes it less likely to cross the node during the critical period. November transits recur at intervals of 7, 13, or 33 years while May transits recur only over the latter two intervals. The following table lists all transits of Mercury from 1924 through 2050.

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Transits of Mercury: 1901-2050 Date Universal Separation* Time (Sun and Mercury) 1924 1927 1937 1940 1953 1957 1960 1970 1973 1986 1993 1999 2003 2006 2016 2019 2032 2039 2049 •

May Nov May Nov Nov May Nov May Nov Nov Nov Nov May Nov May Nov Nov Nov May

08 10 11 11 14 06 07 09 10 13 06 15 07 08 09 11 13 07 07

01:41 05:44 09:00 23:20 16:54 01:14 16:53 08:16 10:32 04:07 03:57 21:41 07:52 21:41 14:57 15:20 08:54 08:46 14:24

85" 129" 955" 368" 862" 907" 528" 114" 26" 471" 927" 963" 708" 423" 319" 76" 572" 822" 512"

(graze)

distance (arc-seconds) between the centers of the Sun and Mercury

To determine whether a transit of Mercury is visible from a specific geographic location, it is simply a matter of calculating the Sun's altitude and azimuth during each phase of the transit using information tabulated in the Seven Century Catalog of Mercury Transit. For the relevant equations and a sample calculation , see Transit Visibility. This web page also has links to several Excel files which perform the calculations automatically when the user inputs the latitude and longitude of any location. In 1716, Edmond Halley published a paper describing exactly how transits could be used to measure the Sun's distance, thereby establishing the absolute scale of the solar system from Kepler's third law. Unfortunately, his method proved somewhat impractical since contact timings of the required accuracy are difficult to make. Nevertheless, the 1761 and 1769 expeditions to observe the transits of Venus gave astronomers their first good value for the Sun's distance.

Photograph of the Transit of Venus on 1882 Dec 06. Taken by students at Vassar College (Sky & Telescope Feb. 1961). All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Because Venus's orbit is considerably larger than Mercury's orbit, transits of Venus are much rarer. Indeed, only six such events have occurred since the invention of the telescope (1631,1639, 1761,1769, 1874 and 1882). Transits of Venus are only possible during early December and June when Venus's orbital nodes pass across the Sun. Transits of Venus show a clear pattern of recurrence at intervals of 8, 121.5, 8 and 105.5 years. The following table lists all transits of Venus during the 800 year period from 1601 through 2400. Transits of Venus: 1601-2400 Date Universal Separation Time (Sun and Venus) 1631 1639 1761 1769 1874 1882 2004 2012 2117 2125 2247 2255 2360 2368

Dec Dec Jun Jun Dec Dec Jun Jun Dec Dec Jun Jun Dec Dec

07 04 06 03 09 06 08 06 11 08 11 09 13 10

05:19 18:25 05:19 22:25 04:05 17:06 08:19 01:28 02:48 16:01 11:30 04:36 01:40 14:43

940" 522" 573" 608" 832" 634" 627" 553" 724" 733" 693" 492" 628" 835"

To determine whether a transit of Venus is visible from a specific geographic location, it is simply a matter of calculating the Sun's altitude and azimuth during each phase of the transit using information tabulated in the Six Millennium Catalog of Venus Transits. For the relevant equations and a sample calculation , see Transit Visibility. This web page also has links to several Excel files which perform the calculations automatically when the user inputs the latitude and longitude of any location. The 2004 transit of Venus will be best seen from Europe,Africa and Asia. However, the final stages of the event will also be visible from the eastern USA and Canada. Since Venus will subtend 61 arcseconds, it should be visible to the naked eye using suitable filtration. The first transit of Venus in 121 years is most eagerly anticipated.

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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2004 Transit of Venus Published in Observer's Handbook 2004, Royal Astronomical Society of Canada The transit or passage of a planet across the face of the Sun is a relatively rare occurrence. As seen from Earth, only transits of Mercury and Venus are possible. On average, there are 13 transits of Mercury each century. In contrast, transits of Venus occur in pairs with more than a century separating each pair.

No living person has seen a transit of Venus because the most recent one occurred in 1882. This situation is about to change since Venus will transit the Sun on Tuesday, 2004 June 08. The entire event will be widely visible from the Europe, Africa and Asia as shown in the map in Figure 1. Japan, Indonesia, the Philippines and Australia will witness the beginning of the transit but the Sun will set before the event ends. Similarly, observers in western Africa, eastern North America, the Caribbean and most of South America will see the end of the event since the transit will already be in progress at sunrise from those locations. All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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The principal events occurring during a transit are conveniently characterized by contacts, analogous to the contacts of an annular solar eclipse. The transit begins with contact I, the instant the planet's disk is externally tangent with the Sun. Shortly after contact I, the planet can be seen as a small notch along the solar limb. The entire disk of the planet is first seen at contact II when the planet is internally tangent with the Sun. During the next several hours, the silhouetted planet slowly traverses the brilliant solar disk. At contact III, the planet reaches the opposite limb and once again is internally tangent with the Sun. Finally, the transit ends at contact IV when the planet's limb is externally tangent to the Sun. Contacts I and II define the phase called ingress while contacts III and IV are known as egress. Position angles for Venus at each contact are measured counterclockwise from the north point on the Sun's disk. Table 1 Geocentric Phases of the 2004 Transit of Venus Event Universal Position Time Angle Contact I Contact II Greatest Contact III Contact IV

05:13:29 05:32:55 08:19:44 11:06:33 11:25:59

116° 119° 166° 213° 216°

The table above gives the times of major events during the transit. Greatest transit is the instant when Venus passes closest to the Sun's center (i.e. - minimum separation). During the 2004 transit, Venus's minimum separation from the Sun is 627 arc-seconds. The position angle is defined as the direction of Venus with respect to the center of the Sun's disk, measured counterclockwise from the celestial north point on the Sun. Figure 2 shows the path of Venus across the Sun's disk and the scale gives the Universal Time of Venus's position at any instant during the transit. The celestial coordinates of the Sun and Venus are provided at greatest transit as well as the times of the major contacts. All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Note that these times are for an observer at Earth's center. The actual contact times for any given observer may differ by up to ± 7 minutes. This is due to effects of parallax since Venus's 58 arc-second diameter disk may be shifted up to 30 arc-seconds from its geocentric coordinates depending on the observer's exact position on Earth. Table 2 and Table 3 list predicted contact times and corresponding altitudes of the Sun for locations throughout Canada and the United States, respectively. Table 4 provides transit predictions for a number of major cities around the world.

Observing the Transit Since the apparent diameter of Venus is nearly 1 arc-minute, it should be possible to see without optical magnification (but using solar filter protection) as it crosses the Sun. Nevertheless, the planet appears to be only 1/32 of the Sun's apparent diameter so a pair of binoculars or a small telescope at modest power will offer a much more satisfying view. Naturally, all binoculars and telescopes must be suitably equipped with adequate filtration to ensure safe solar viewing. The visual and photographic requirements for observing a transit are identical to those for solar viewing. Amateurs can make a scientific contribution by timing the four contacts at ingress and egress. Observing techniques and equipment are similar to those used for lunar occultations. Since poor seeing often increases the uncertainty in contact timings, an estimate of the possible error associated with each timing should be included. Transit timings and geographic coordinates of the observing site (measured with a topographic map or GPS receiver) should be sent to: A. L. P. O. Mercury/Venus Transit Section, P.. Box 16131, San Francisco, CA 94116, USA. The European Southern Observatory (ESO) is organizing a network of amateur astronomers and students to measure Earth's distance from the Sun during the transit. For more information, see their web site at: http://www.eso.org/outreach/eduoff/vt-2004/ White light observations of contacts I and IV are not technically possible since Venus is only visible after contact I and before contact IV. However, if Hydrogen-alpha filtration is available, the planet will be visible against either prominences or the chromosphere before and after contacts I and IV, respectively. Observations of contacts II and III also require amplification. They are defined as the two instants when the planet appears internally tangent to the Sun. However, just before contact II, the socalled black drop effect is seen. At that time, the transiting planet seems to be attached to the Sun's limb by a thin column or thread. When the thread breaks and the planet is completely surrounded by sunlight, this marks the true instant of contact II. Contact III occurs in exactly the reverse order. Atmospheric seeing often makes it difficult to measure contact timings with a precision better than several seconds (see "black drop" effect below).

Frequency of Transits The orbit of Venus is inclined 3.4° with respect to Earth's orbit. It intersects the ecliptic at two points or nodes which cross the Sun each year during early June and December. If Venus happens to pass through inferior conjunction at that time, a transit will occur. Although Venus's orbital period is only 224.7 days, its synodic period (conjunction to conjunction) is 583.9 days. Due to its inclination, most inferior conjunctions of Venus do not result in a transit because the planet passes too far above or below the ecliptic and does not cross the face of the Sun. Venus transits currently recur at intervals of 8, 105.5, 8 and 121.5 years. Since the invention of the telescope (1610), there have only been six transits as listed in table 5.

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Table 5 Transits of Venus: 1601-2200 Date Universal Separation Time 1631 1639 1761 1769 1874 1882 2004 2012 2117 2125

Dec Dec Jun Jun Dec Dec Jun Jun Dec Dec

07 04 06 03 09 06 08 06 11 08

05:19 18:26 05:19 22:25 04:07 17:06 08:20 01:28 02:48 16:01

939 524 570 609 830 637 627 553 724 733

" " " " " " " " " "

The next transit of Venus will occur in 2012. More than a century will elapse before the next pair of transits in 2117 and 2125. During the 6,000 year period from 2000 BC to AD 4000, a total of 81 transits of Venus occur.

History of Transits When Johannes Kepler published the Rudolphine Tables of planetary motion in 1627, they permitted him to make detailed and fairly accurate predictions of the future positions and interesting alignments of the planets. Much to his surprise, he discovered that both Mercury and Venus would transit the Sun's disk in late 1631. Kepler died before the transits, but French astronomer Pierre Gassendi succeeded in becoming the first to witness a transit of Mercury. The following month, he tried to observe the transit of Venus, but modern calculations show that it was not visible from Europe. Although Kepler's predictions suggested that the next Venus transit would not occur until the following century, a promising, young British amateur astronomer named Jeremiah Horrocks believed that another transit would occur in 1639. His calculations were completed just a month before the event so there was little time to spread the word. Horrocks and his good friend William Crabtree were apparently the only ones to witness the transit of Venus on 1639 Dec 04 which allowed them to accurately measure the apparent diameter of the planet. Unfortunately, both Horrocks and Crabtree died young before either of them reached their full potential. Nearly forty years later a young Edmond Halley observed the 1677 transit of Mercury while completing a southern hemisphere star catalog from Saint Helena's Island. Halley realized that the careful timing of transits could be used to determine the distance of Earth from the Sun. The technique relied on observations made from the far corners of the globe. The effect of parallax on the remote observers would allow them to derive the absolute distance scale of the entire solar system. Venus transits were better suited to this goal than were Mercury transits because Venus is closer to Earth and consequently exhibits a larger parallax. Halley challenged future generations to organize major expeditions to the ends of Earth in order to observe the transits of 1761 and 1769. Many scientific expeditions were mounted but the results were disappointing. The accurate timings needed were not possible due to a mysterious "black drop" effect in which the edge of Venus's disk appeared to deform and cling to the limb of the Sun. Undeterred by the results, another major observing campaign was mounted by many nations for the Venus transits of 1874 and 1882. Again, the "black drop" limited the precision of the observations and the determination of the Sun's distance. Modern analyses show that the "black drop" is the result of seeing effects due to Earth's turbulent atmosphere. All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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The distance to the Sun and planets can now be measured extremely accurately using radar, so the 2004 transit will be of much less scientific importance. Still, it is a remarkably rare event which was of great value during the early the history of modern astronomy.

An image of one of the 1700 plates taken worldwide during the 1882 transit, showing Venus crossing the disk of the Sun.

Commemorative stamp of the 1769 Cook’s expedition to Tahiti

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Predictions for the 2004 Transit of Venus Fred Espenak, NASA's GSFC and Jay Anderson, Environment Canada

Introduction A transit of Venus across the disk of the Sun is among the rarest of planetary alignments. The last transit occurred 120 years ago in 1882, while the next one takes place on 2004 June 08. Figure 1 shows the geocentric path of Venus across the Sun.

Figure 1 The scale along the track gives the Universal Time1 of Venus's position at any instant. The planet moves westward with respect to the Sun and inscribes a chord through the Sun's 1

Universal Time or UT is the basis for the worldwide system of civil time. It is often referred to as Greenwich Mean Time although UT is actually based on atomic clock time rather than the Sun's mean motion. All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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southern hemisphere. Moving with an angular speed of 3.2 arc-minutes per hour, Venus takes about 6.2 hours to cross the Sun's disk. The transit begins with contact I when the limb of Venus is externally tangent with the Sun. It takes about nineteen minutes for the planet's disk to cross the solar limb where it becomes internally tangent with the Sun at contact II. The period between contacts I and II is known as ingress. At the end of ingress, the entire disk of Venus is seen silhouetted against the Sun's disk as it begins its slow six-hour passage across our star. Contact III occurs when Venus reaches and first touches the opposite limb of the Sun. Another nineteen minutes elapse as the planet gradually exits the solar disk. Finally, the transit ends with contact IV when Venus's disk completely exits the Sun and the planet vanishes from sight. The period from contact III to IV is referred to as egress.

Table 1 Geocentric Phases of the 2004 Transit of Venus Event

Universal Time

Description

Contact I

05:13:29

ingress begins

Contact II

05:32:55

ingress ends

Greatest

08:19:44

minimum angular distance

Contact III

11:06:33

egress begins

Contact IV

11:25:59

egress ends

Table 1 gives the times of major events during the transit. Greatest transit is the instant when Venus passes closest to the Sun's center. These contact times are actually for an observer at Earth's center. The contact times at other location will differ by up to seven minutes. This effect is due to parallax since Venus's position will shift slightly2 depending on the observer's geographic coordinates on Earth

Transit Contact Times for Cities Around the World The following tables provide contact times and corresponding altitudes of the Sun for hundreds of cities and locations throughout the world. For convenience, the times of sunrise and sunset for each city are also provided. Greatest transit is the instant when Venus passes closest to the Sun's center (i.e. - minimum angular separation). Please note that all times listed are in Universal Time (UT).

2

Venus's 58 arc-second disk may be shifted up to 30 arc-seconds from its geocentric coordinates depending on the observer's geographic position on Earth. All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Circumstances for Europe Venus will pass across the disk of the Sun during a rare transit on 2004 June 08. This uncommon event will be visible from many locations including Europe, Asia, Africa, Australia and eastern North and South America. The following table presents detailed predictions for a number of cities. First, the approximate times of sunrise and sunset (Sun's upper limb) are given in Universal Time for a given city. The starting (ingress) and ending (egress) times for each stage of the transit are provided along with the corresponding altitude of the Sun.

For locations in other parts of the world, see http://sunearth.gsfc.nasa.gov/eclipse/transit/TV2004.html#city . Location Name

Sunrise Sunset h

m

h

m

------------------- T r a n s i t C o n t a c t s ------------------Contact I Contact II Contact III Contact IV -------------------------------------------------------External Sun Internal Sun Greatest Sun Internal Sun External Sun Ingress Alt Ingress Alt Transit Alt Egress Alt Egress Alt h m s ° h m s ° h m s ° h m s ° h m s °

Albania Tirane

03:08

18:11

05:20:01

22

05:39:40

26

08:22:38

56

11:04:13

71

11:23:31

69

Austria Graz Linz Wien (Vienna)

03:05 03:04 02:53

18:49 18:59 18:54

05:19:56 05:19:54 05:19:51

20 20 21

05:39:39 05:39:39 05:39:35

24 23 24

08:22:27 08:22:25 08:22:19

51 50 51

11:03:53 11:03:49 11:03:43

66 65 65

11:23:16 11:23:14 11:23:08

65 64 64

Belarus Brest Gomel' Grodno Minsk Mogil'ov Vitebsk

02:08 01:37 01:58 01:37 01:31 01:23

18:40 18:13 18:49 18:40 18:24 18:33

05:19:29 05:19:13 05:19:24 05:19:16 05:19:11 05:19:07

26 31 26 29 30 30

05:39:11 05:38:52 05:39:07 05:38:58 05:38:51 05:38:48

29 34 29 31 33 33

08:21:38 08:21:12 08:21:30 08:21:17 08:21:08 08:21:03

53 55 52 53 54 53

11:03:01 11:02:39 11:02:53 11:02:41 11:02:34 11:02:28

60 58 58 57 57 56

11:22:28 11:22:05 11:22:20 11:22:09 11:22:01 11:21:56

59 56 57 56 55 54

Belgium Antwerpen

03:30

19:53

05:19:53

14

05:39:44

17

08:22:35

43

11:03:56

61

11:23:26

61

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Location Name

Sunrise Sunset h

Brussels Charleroi Gent Hasselt Liege

m

h

m

------------------- T r a n s i t C o n t a c t s ------------------Contact I Contact II Contact III Contact IV -------------------------------------------------------External Sun Internal Sun Greatest Sun Internal Sun External Sun Ingress Alt Ingress Alt Transit Alt Egress Alt Egress Alt h m s ° h m s ° h m s ° h m s ° h m s °

03:32 03:34 03:34 03:28 03:28

19:51 19:49 19:55 19:48 19:45

05:19:55 05:19:56 05:19:54 05:19:54 05:19:55

14 14 14 15 15

05:39:46 05:39:47 05:39:46 05:39:44 05:39:45

17 17 17 18 18

08:22:37 08:22:39 08:22:37 08:22:34 08:22:35

43 43 42 43 43

11:03:59 11:04:01 11:03:59 11:03:56 11:03:57

61 62 61 61 62

11:23:28 11:23:30 11:23:29 11:23:25 11:23:26

62 62 62 62 62

Bosnia & Herzegowina Sarajevo 03:06

18:25

05:19:59

22

05:39:39

25

08:22:32

54

11:04:02

69

11:23:23

68

Bulgaria Plovdiv Sofija (Sofia) Varna

02:47 02:45 02:29

17:54 18:06 17:46

05:19:50 05:19:52 05:19:41

26 25 28

05:39:26 05:39:29 05:39:16

30 29 32

08:22:16 08:22:19 08:21:59

59 58 60

11:03:51 11:03:53 11:03:35

69 69 67

11:23:10 11:23:12 11:22:53

67 67 64

Croatia Zagreb

03:08

18:42

05:19:58

20

05:39:41

24

08:22:32

52

11:03:59

67

11:23:21

66

Cyprus Lesmesos Nicosia

02:36 02:30

16:58 17:01

05:19:36 05:19:35

31 32

05:39:03 05:39:02

35 36

08:22:06 08:22:03

68 68

11:04:02 11:03:58

69 69

11:23:13 11:23:10

66 66

Czech Republic Brno Ostrava Praha

02:51 02:41 02:52

18:54 18:50 19:11

05:19:48 05:19:44 05:19:49

21 23 20

05:39:32 05:39:28 05:39:34

25 26 23

08:22:13 08:22:05 08:22:16

50 51 49

11:03:37 11:03:29 11:03:38

64 63 63

11:23:02 11:22:54 11:23:04

63 62 62

Denmark Arhus Kobenhavn

02:34 02:29

20:02 19:48

05:19:32 05:19:32

19 20

05:39:22 05:39:21

22 23

08:21:54 08:21:51

44 45

11:03:13 11:03:10

57 57

11:22:45 11:22:42

57 57

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Location Name

Sunrise Sunset h

m

h

m

------------------- T r a n s i t C o n t a c t s ------------------Contact I Contact II Contact III Contact IV -------------------------------------------------------External Sun Internal Sun Greatest Sun Internal Sun External Sun Ingress Alt Ingress Alt Transit Alt Egress Alt Egress Alt h m s ° h m s ° h m s ° h m s ° h m s °

Finland Helsinki

01:01

19:38

05:19:00

27

05:38:45

30

08:20:57

47

11:02:19

52

11:21:52

51

France Bethune Bordeaux Cannes Clermont Ferrand Grenoble Le Havre Lens Lille Lyon Marseille

03:41 04:17 03:53 04:00 03:52 03:56 03:40 03:37 03:49 03:58

19:56 19:46 19:09 19:34 19:21 20:01 19:55 19:57 19:30 19:17

05:19:56 05:20:13 05:20:13 05:20:10 05:20:10 05:20:00 05:19:56 05:19:56 05:20:09 05:20:15

13 9 14 12 13 11 13 13 13 12

05:39:48 05:40:05 05:40:00 05:40:00 05:39:59 05:39:53 05:39:48 05:39:47 05:39:58 05:40:03

16 12 17 15 17 14 16 16 16 16

08:22:42 08:23:20 08:23:09 08:23:07 08:23:04 08:22:53 08:22:42 08:22:41 08:23:03 08:23:15

42 41 46 43 45 40 42 42 44 45

11:04:05 11:04:50 11:04:39 11:04:35 11:04:32 11:04:17 11:04:05 11:04:03 11:04:30 11:04:45

61 65 69 66 67 61 61 61 66 69

11:23:34 11:24:16 11:24:02 11:24:00 11:23:56 11:23:47 11:23:34 11:23:33 11:23:56 11:24:08

62 67 69 67 68 63 62 62 67 69

Nancy Nantes Nice Paris Rouen Saint Etienne Strasbourg Toulon Toulouse Tours

03:35 04:13 03:51 03:48 03:52 03:56 03:26 03:59 04:12 04:03

19:33 19:58 19:09 19:52 19:57 19:27 19:30 19:12 19:35 19:50

05:20:00 05:20:07 05:20:13 05:20:01 05:20:00 05:20:10 05:19:59 05:20:15 05:20:16 05:20:06

15 9 14 12 12 13 16 13 10 11

05:39:50 05:40:00 05:40:00 05:39:53 05:39:52 05:40:00 05:39:48 05:40:03 05:40:06 05:39:58

18 13 17 15 15 16 19 16 13 14

08:22:44 08:23:09 08:23:08 08:22:52 08:22:52 08:23:06 08:22:41 08:23:14 08:23:23 08:23:04

44 40 46 42 41 44 45 46 42 41

11:04:08 11:04:36 11:04:37 11:04:16 11:04:16 11:04:34 11:04:05 11:04:45 11:04:53 11:04:30

64 63 69 63 62 66 64 69 67 63

11:23:35 11:24:05 11:24:00 11:23:45 11:23:45 11:23:59 11:23:31 11:24:07 11:24:18 11:23:58

64 64 69 64 63 67 64 70 68 65

Valenciennes

03:38

19:52

05:19:56

14

05:39:48

17

08:22:41

42

11:04:04

61

11:23:33

62

Germany Aachen Augsburg

03:26 03:18

19:44 19:13

05:19:54 05:19:57

15 18

05:39:44 05:39:44

18 21

08:22:33 08:22:34

44 47

11:03:55 11:03:58

61 64

11:23:24 11:23:23

62 64

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Location Name

Sunrise Sunset h

m

h

m

------------------- T r a n s i t C o n t a c t s ------------------Contact I Contact II Contact III Contact IV -------------------------------------------------------External Sun Internal Sun Greatest Sun Internal Sun External Sun Ingress Alt Ingress Alt Transit Alt Egress Alt Egress Alt h m s ° h m s ° h m s ° h m s ° h m s °

Berlin Bielefeld Bochum Bonn Braunschweig Bremen Darmstadt Dortmund

02:47 03:09 03:17 03:22 03:00 03:01 03:20 03:16

19:24 19:41 19:43 19:40 19:34 19:47 19:29 19:42

05:19:42 05:19:48 05:19:51 05:19:53 05:19:46 05:19:44 05:19:55 05:19:51

20 17 16 16 18 18 17 16

05:39:29 05:39:38 05:39:41 05:39:43 05:39:34 05:39:34 05:39:43 05:39:40

23 20 19 19 21 20 20 19

08:22:06 08:22:21 08:22:27 08:22:31 08:22:15 08:22:15 08:22:32 08:22:26

47 45 44 44 46 44 46 44

11:03:27 11:03:42 11:03:48 11:03:53 11:03:35 11:03:35 11:03:54 11:03:47

60 61 61 62 61 60 63 61

11:22:55 11:23:11 11:23:17 11:23:21 11:23:04 11:23:04 11:23:22 11:23:16

60 61 61 62 61 60 63 61

Dresden Duisburg Dusseldorf Essen Frankfurt am Main Gelsenkirchen Halle Hamburg Hannover Chemnitz

02:54 03:20 03:21 03:18 03:16 03:18 02:58 02:53 03:02 02:58

19:15 19:44 19:43 19:44 19:33 19:44 19:24 19:45 19:38 19:17

05:19:46 05:19:51 05:19:52 05:19:51 05:19:54 05:19:51 05:19:47 05:19:42 05:19:46 05:19:48

20 16 16 16 17 16 19 18 18 19

05:39:33 05:39:41 05:39:42 05:39:41 05:39:43 05:39:41 05:39:34 05:39:31 05:39:35 05:39:35

23 19 19 19 20 19 22 21 21 23

08:22:13 08:22:28 08:22:29 08:22:27 08:22:31 08:22:27 08:22:15 08:22:09 08:22:16 08:22:16

48 44 44 44 45 44 47 45 45 48

11:03:34 11:03:50 11:03:51 11:03:49 11:03:53 11:03:48 11:03:36 11:03:29 11:03:36 11:03:38

62 61 61 61 62 61 61 59 60 62

11:23:01 11:23:19 11:23:20 11:23:18 11:23:20 11:23:17 11:23:04 11:22:59 11:23:05 11:23:05

62 61 62 61 63 61 61 59 60 62

Karlsruhe Kassel Kiel Koln (Cologne) Leipzig Lubeck Magdeburg Mannheim Monchengladbach Munchen

03:25 03:09 02:49 03:21 02:58 02:50 02:56 03:22 03:22 03:10

19:26 19:33 19:48 19:41 19:22 19:43 19:29 19:28 19:45 19:15

05:19:58 05:19:50 05:19:39 05:19:53 05:19:47 05:19:40 05:19:45 05:19:56 05:19:52 05:19:57

16 17 19 16 19 19 19 16 16 18

05:39:46 05:39:38 05:39:28 05:39:43 05:39:34 05:39:29 05:39:33 05:39:45 05:39:42 05:39:44

19 20 21 19 22 22 22 19 19 21

08:22:37 08:22:22 08:22:05 08:22:30 08:22:15 08:22:06 08:22:13 08:22:35 08:22:30 08:22:33

46 45 45 44 47 45 46 46 44 48

11:04:00 11:03:43 11:03:24 11:03:52 11:03:36 11:03:25 11:03:33 11:03:57 11:03:52 11:03:57

64 61 58 61 62 59 61 63 61 65

11:23:27 11:23:12 11:22:54 11:23:21 11:23:04 11:22:55 11:23:02 11:23:24 11:23:21 11:23:23

64 62 59 62 61 59 61 63 62 65

Munster Nurnberg Osnabruck Saarbrucken

03:13 03:07 03:10 03:30

19:44 19:22 19:44 19:33

05:19:49 05:19:54 05:19:48 05:19:58

17 18 17 15

05:39:39 05:39:41 05:39:37 05:39:47

19 21 20 18

08:22:23 08:22:28 08:22:21 08:22:40

44 47 44 45

11:03:44 11:03:51 11:03:41 11:04:03

61 63 60 63

11:23:13 11:23:17 11:23:11 11:23:30

61 63 61 64

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

16/39

Location Name

Sunrise Sunset h

m

h

m

------------------- T r a n s i t C o n t a c t s ------------------Contact I Contact II Contact III Contact IV -------------------------------------------------------External Sun Internal Sun Greatest Sun Internal Sun External Sun Ingress Alt Ingress Alt Transit Alt Egress Alt Egress Alt h m s ° h m s ° h m s ° h m s ° h m s °

Stuttgart Wiesbaden Wuppertal

03:23 03:20 03:19

19:22 19:32 19:42

05:19:58 05:19:55 05:19:52

17 16 16

05:39:46 05:39:43 05:39:41

20 19 19

08:22:37 08:22:32 08:22:28

46 45 44

11:04:00 11:03:54 11:03:49

64 62 61

11:23:26 11:23:22 11:23:18

64 63 62

Greece Athens ThessalonIki (Sal*

03:02 02:58

17:47 17:57

05:19:58 05:19:56

24 24

05:39:33 05:39:33

28 28

08:22:36 08:22:29

60 58

11:04:19 11:04:06

73 71

11:23:34 11:23:23

70 69

Hungary Budapest

02:46

18:39

05:19:49

23

05:39:31

26

08:22:14

53

11:03:39

65

11:23:03

64

Ireland Dublin

03:59

20:49

05:19:46

9

05:39:43

12

08:22:41

36

11:04:05

56

11:23:39

57

Italy Bari Bergamo Bologna Cagliari Catania Florence Genoa Messina Mestre Milan

03:22 03:34 03:32 03:58 03:40 03:35 03:39 03:36 03:24 03:37

18:22 19:07 18:56 18:47 18:18 18:53 19:07 18:18 18:56 19:08

05:20:07 05:20:06 05:20:07 05:20:20 05:20:15 05:20:09 05:20:10 05:20:14 05:20:04 05:20:07

20 16 17 14 18 17 15 18 18 16

05:39:47 05:39:52 05:39:52 05:40:04 05:39:55 05:39:54 05:39:56 05:39:53 05:39:49 05:39:53

24 19 20 17 22 20 19 22 21 19

08:22:50 08:22:51 08:22:52 08:23:24 08:23:12 08:22:56 08:22:59 08:23:07 08:22:45 08:22:53

54 48 49 49 54 49 47 54 49 47

11:04:24 11:04:17 11:04:20 11:05:00 11:04:52 11:04:25 11:04:28 11:04:46 11:04:11 11:04:20

72 67 68 73 75 69 68 75 67 67

11:23:42 11:23:41 11:23:43 11:24:19 11:24:08 11:23:47 11:23:51 11:24:03 11:23:35 11:23:44

71 67 68 74 74 69 68 74 67 67

Naples Padova Palermo Rome

03:32 03:26 03:43 03:34

18:32 18:57 18:28 18:44

05:20:11 05:20:04 05:20:17 05:20:11

18 18 17 17

05:39:53 05:39:49 05:39:58 05:39:55

22 21 20 21

08:23:00 08:22:46 08:23:15 08:23:01

52 49 52 51

11:04:34 11:04:13 11:04:54 11:04:33

72 67 75 71

11:23:53 11:23:36 11:24:11 11:23:53

71 67 74 71

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

17/39

Location Name

Sunrise Sunset h

m

h

m

------------------- T r a n s i t C o n t a c t s ------------------Contact I Contact II Contact III Contact IV -------------------------------------------------------External Sun Internal Sun Greatest Sun Internal Sun External Sun Ingress Alt Ingress Alt Transit Alt Egress Alt Egress Alt h m s ° h m s ° h m s ° h m s ° h m s °

Salerno Turin Venice Verona

03:31 03:44 03:23 03:30

18:29 19:12 18:56 19:01

05:20:11 05:20:09 05:20:04 05:20:05

18 15 18 17

05:39:52 05:39:56 05:39:48 05:39:51

22 18 21 20

08:22:59 08:23:00 08:22:44 08:22:48

53 46 49 49

11:04:33 11:04:27 11:04:11 11:04:15

72 67 67 67

11:23:52 11:23:51 11:23:34 11:23:39

72 68 67 67

Kaliningrad Kaliningrad

02:05

19:09

05:19:26

25

05:39:11

27

08:21:35

49

11:02:56

58

11:22:25

57

Latvia Riga

01:35

19:10

05:19:13

27

05:38:57

29

08:21:15

49

11:02:36

55

11:22:06

54

Lithuania Kaunas Vilnius

01:50 01:46

18:57 18:49

05:19:20 05:19:18

26 27

05:39:03 05:39:01

29 30

08:21:25 08:21:21

51 52

11:02:46 11:02:44

57 57

11:22:15 11:22:12

56 56

Luxembourg Luxembourg

03:26

19:43

05:19:58

15

05:39:47

18

08:22:40

44

11:04:02

63

11:23:30

63

Macedonia Skopje

02:57

18:10

05:19:57

23

05:39:35

27

08:22:29

57

11:04:04

70

11:23:22

68

Malta Valletta

03:45

18:17

05:20:18

17

05:39:58

21

08:23:20

54

11:05:04

77

11:24:19

76

Moldova Kisin'ov

02:12

17:55

05:19:31

29

05:39:08

33

08:21:41

58

11:03:12

63

11:22:33

61

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

18/39

Location Name

Sunrise Sunset h

m

h

m

------------------- T r a n s i t C o n t a c t s ------------------Contact I Contact II Contact III Contact IV -------------------------------------------------------External Sun Internal Sun Greatest Sun Internal Sun External Sun Ingress Alt Ingress Alt Transit Alt Egress Alt Egress Alt h m s ° h m s ° h m s ° h m s ° h m s °

Monaco Monaco

03:49

19:10

05:20:13

14

05:40:00

17

08:23:07

47

11:04:37

69

11:24:00

69

Netherlands Amsterdam Arnhem Eindhoven Enschede Heerlen Rotterdam S'Gravenhage Utrecht

03:21 03:20 03:25 03:15 03:25 03:26 03:26 03:22

19:57 19:51 19:50 19:48 19:45 19:56 19:58 19:55

05:19:49 05:19:50 05:19:52 05:19:49 05:19:53 05:19:51 05:19:50 05:19:50

15 16 15 16 15 15 15 15

05:39:40 05:39:41 05:39:43 05:39:39 05:39:44 05:39:42 05:39:42 05:39:41

18 18 18 19 18 18 18 18

08:22:27 08:22:27 08:22:31 08:22:24 08:22:33 08:22:31 08:22:30 08:22:28

42 43 43 44 44 42 42 43

11:03:48 11:03:48 11:03:53 11:03:44 11:03:55 11:03:52 11:03:51 11:03:49

60 60 61 60 61 60 60 60

11:23:18 11:23:18 11:23:22 11:23:14 11:23:23 11:23:22 11:23:21 11:23:19

60 61 61 61 62 61 61 61

Norway Oslo

01:57

20:35

05:19:17

20

05:39:08

23

08:21:32

42

11:02:51

53

11:22:26

53

Poland Bialystok Bialystok Bydgoszcz Czestochowa Gdansk Gdynia Katowice Krakow Lodz Lublin

02:04 02:04 02:25 02:33 02:14 02:14 02:36 02:30 02:27 02:17

18:49 18:49 19:09 18:52 19:15 19:16 18:50 18:49 18:55 18:40

05:19:27 05:19:27 05:19:35 05:19:40 05:19:30 05:19:29 05:19:42 05:19:41 05:19:37 05:19:33

26 26 23 23 23 23 23 24 24 25

05:39:09 05:39:09 05:39:20 05:39:24 05:39:15 05:39:15 05:39:25 05:39:24 05:39:21 05:39:15

29 29 26 26 26 26 26 27 27 29

08:21:35 08:21:35 08:21:50 08:21:58 08:21:42 08:21:42 08:22:01 08:21:59 08:21:52 08:21:45

52 52 49 51 49 49 51 52 51 53

11:02:57 11:02:57 11:03:11 11:03:21 11:03:03 11:03:02 11:03:24 11:03:23 11:03:15 11:03:09

59 59 60 62 58 58 62 62 61 61

11:22:25 11:22:25 11:22:39 11:22:47 11:22:32 11:22:31 11:22:50 11:22:48 11:22:41 11:22:35

58 58 59 61 58 58 62 62 60 60

Poznan Sosnowiec Szczecin Warsaw

02:33 02:36 02:37 02:15

19:09 18:49 19:25 18:55

05:19:38 05:19:42 05:19:38 05:19:33

22 23 21 25

05:39:24 05:39:25 05:39:25 05:39:16

25 26 24 28

08:21:57 08:22:01 08:21:58 08:21:46

49 51 47 51

11:03:18 11:03:24 11:03:19 11:03:08

60 62 59 60

11:22:46 11:22:49 11:22:48 11:22:35

60 61 59 59

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

19/39

Location Name

Sunrise Sunset h

m

h

m

------------------- T r a n s i t C o n t a c t s ------------------Contact I Contact II Contact III Contact IV -------------------------------------------------------External Sun Internal Sun Greatest Sun Internal Sun External Sun Ingress Alt Ingress Alt Transit Alt Egress Alt Egress Alt h m s ° h m s ° h m s ° h m s ° h m s °

Wroclaw

02:37

19:05

05:19:42

22

05:39:27

25

08:22:03

50

11:03:25

62

11:22:52

61

Portugal Lisbon Porto

05:11 05:03

20:00 20:04

05:20:24 05:20:19

1 2

05:40:19 05:40:15

4 6

08:24:08 08:23:54

35 35

11:05:53 11:05:35

65 64

11:25:18 11:25:01

68 67

Romania Brasov Bucharest Cluj-Napoca Constanta Craiova Galati Iasi Ploiesti Timisoara

02:30 02:31 02:29 02:23 02:43 02:21 02:16 02:31 02:48

18:03 17:58 18:20 17:46 18:05 17:52 18:01 17:58 18:21

05:19:41 05:19:43 05:19:43 05:19:37 05:19:48 05:19:36 05:19:34 05:19:42 05:19:50

27 27 26 29 26 29 28 27 24

05:39:19 05:39:19 05:39:22 05:39:12 05:39:26 05:39:12 05:39:11 05:39:19 05:39:30

30 31 29 32 29 32 32 31 27

08:21:59 08:22:02 08:22:01 08:21:53 08:22:11 08:21:50 08:21:45 08:22:00 08:22:14

57 58 56 60 57 59 58 58 55

11:03:29 11:03:34 11:03:30 11:03:27 11:03:43 11:03:23 11:03:15 11:03:32 11:03:43

65 66 65 66 67 65 63 66 66

11:22:50 11:22:54 11:22:52 11:22:46 11:23:03 11:22:43 11:22:37 11:22:52 11:23:04

64 64 63 63 65 63 62 64 65

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

20/39

World Visibility of 2004 Transit of Venus

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

21/39

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

22/39

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

23/39

2004 and 2012 Transits of Venus Based on a poster presented at the conference Scientific Frontiers in Research on Extrasolar Planets Carnegie Institution, 2002 June 18-21

Introduction Transits of Venus across the disk of the Sun are among the rarest of planetary alignments. Indeed, only six such events have occurred since the invention of the telescope (1631, 1639, 1761, 1769, 1874 and 1882). The next two transits of Venus will occur on 2004 June 08 and 2012 June 06. The principal events occurring during a transit are characterized by contacts. The event begins with contact I which is the instant when the planet's disk is externally tangent with the Sun. The entire disk of the Venus is first seen at contact II when the planet is internally tangent with the Sun. During the next several hours, Venus gradually traverses the solar disk at a relative angular rate of approximately 4 arc-min/hr. At contact III, the planet reaches the opposite limb and is once again internally tangent with the Sun. The transit ends at contact IV when the planet's limb is externally tangent to the Sun. Contacts I and II define the phase called ingress while contacts III and IV are known as egress. Greatest transit is the instant of minimum angular separation between Venus and the Sun as seen from Earth's geocenter.

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

24/39

Figure 1 illustrates the geocentric observing geometry of each transit across the Sun (celestial north is up). The 2004 transit crosses the Sun's southern hemisphere while the 2012 event crosses the northern hemisphere. The position of Venus at each contact is shown along with its path as a function of Universal Time. Each transit lasts over six hours. The apparent semi-diameters of Venus and the Sun are 29 arc-seconds and 945 arc-seconds respectively. This 1:32.6 diameter ratio results in an effective 0.001 magnitude drop in the Sun's integrated magnitude due to the transit. Geocentric contact times and instant of greatest transit appear to the left corners of figure 1

Geographic Visibility of 2004 June 08 The global visibility of the 2004 transit is illustrated with the world map in figure. The entire transit (all four contacts) is visible from Europe, Africa (except western parts), Middle East, and most of Asia (except eastern parts). The Sun sets while the transit is still in progress from Australia, Indonesia, Japan, Philippines, Korea, easternmost China and Southeast Asia. Similarly, the Sun rises with the transit already in progress for observers in western Africa, eastern North America, the Caribbean and most of South America. None of the transit will be visible from southern Chile or Argentina, western North America, Hawaii or New Zealand. The horizontal parallax of Venus (~30 arc-sec) introduces a topocentric correction of up to ±7 minutes with respect to the geocentric contact times for observers at different geographic locations. Topocentric contact times (Universal Time) and corresponding altitudes of the Sun are presented for over one hundred cities in table 1a (international) and table 1b (USA).

Geographic Visibility of 2012 June 06 The global visibility of the 2012 transit is illustrated with the world map in figure 3 . The entire transit (all four contacts) is visible from northwestern North America, Hawaii, the western Pacific, northern Asia, Japan, Korea, eastern China, Philippines, eastern Australia, and New Zealand. The Sun sets while the transit is still in progress from most of North America, the Caribbean, and northwest South America. Similarly, the transit is already in progress at sunrise for observers in central Asia, the Middle East, Europe, and eastern Africa,. No portion of the transit will be visible from Portugal or southern Spain, western Africa, and the southeastern 2/3 of South America. The horizontal parallax of Venus (~30 arc-sec) introduces a topocentric correction of up to ±7 minutes with respect to the geocentric contact times for observers at different geographic locations. Topocentric contact times (Universal Time) and corresponding altitudes of the Sun are presented for over one hundred cities in table 2a (international) and table 2b (USA).

Frequency of Transits Transits of Venus are only possible during early December and early June when Venus's orbital nodes pass across the Sun. If Venus reaches inferior conjunction at this time, a transit will occur. Transits show a clear pattern of recurrence at intervals of 8, 121.5, 8 and 105.5 years. The next pair of Venus transits occur over a century from now on 2117 Dec 11 and 2125 Dec 08. Edmund Halley first realized that transits of Venus could be used to measure the Sun's distance, thereby establishing the absolute scale of the solar system from Kepler's third law. Unfortunately, his method proved impractical since contact timings of the desired accuracy are impossible due to the effects of atmospheric seeing and diffraction. Nevertheless, the 1761 and 1769 expeditions to observe the transits of Venus gave astronomers their first good value for the Sun's distance. All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

25/39

The planet Mercury can also transit the Sun. Since Mercury orbits the Sun more quickly than does Venus, it undergoes transits much more frequently. There are about 13 or 14 transits of Mercury each century. All Mercury transits fall within several days of 8 May and 10 November. During November transits, Mercury is near perihelion and exhibits a disk only 10 arc-seconds in diameter. By comparison, the planet is near aphelion during May transits and appears 12 arc-seconds across. However, the probability of a May transit is smaller by a factor of almost two. Mercury's slower orbital motion at aphelion makes it less likely to cross the node during the critical period. November transits recur at intervals of 7, 13, or 33 years while May transits recur only over the latter two intervals. The next two transits of Mercury are on 2003 May 07 and 2006 Nov 08. For details on the first event, see: 2003 Transit of Mercury

Additional Comments The upcoming transits of Venus offer a unique and rare opportunity to develop and test new techniques which can be applied to the detection and characterization of extrasolar planets.

Orbit’s planes

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

26/39

Six Millennium Catalog: 2000 BCE to 4000 CE A transit is the passage of a planet across the Sun's bright disk. At this time, the planet can be seen as a small black disk slowly moving in front of the Sun. The orbits of Mercury and Venus lie inside Earth's orbit, so they are the only planets which can pass between Earth and Sun to produce a transit. Transits are very rare astronomical events. In the case of Venus, there are on average two transits every one and a quarter centuries. A transit of Venus occurs only if the planet is in inferior conjunction with the Sun (between Earth and Sun) and is also crossing the through Earth's orbital plane (the Ecliptic). During the present period in Earth's history, Venus's orbit crosses Earth's orbital plane in early June and early December each year. If the Venus is passing between the Earth and Sun at that time, a transit will be seen. During the six millennium period 2000 BCE to 4000 CE1, Earth experiences 81 transits of Venus across the Sun. These events can be organized into two groups: All Transits = 81 = 100.0% June (Descending Node2) = 44 = 54.3 % December (Ascending Node3) = 37 = 45.7 %

When a transit of Venus occurs, a second one often follows eight years later. This is because the orbital periods of Venus (224.701 days) and Earth (365.256 days) are in an 8 year (2922 days) resonance with each other. In other words, in the time it takes Earth to orbit the Sun eight times, Venus completes almost exactly thirteen revolutions about the Sun. As a result, Venus and Earth line up in the same positions with respect to the Sun. Actually, the two orbital periods are not quite commensurate with each other since Venus arrives at the eight year rendezvous about 22 hours earlier that Earth. By the third eight-year cycle, Venus arrives too early for a transit to occur. The next transit season occurs either 105.5 years or 121.5 years later at the opposite node of Venus' orbit. Once again, a pair of transits will often occur separated by eight years. This recurrence pattern of 8 + 105.5 + 8 + 121.5 years can be seen repeating itself in the catalog of Venus transits. An example of the pattern can be seen in the transits of 1631, 1639, 1761, 1769, 1874, 1882, 2004 and 2012. Occasionally, one of the eight year "double-transits" may disappear from the catalog for several centuries because one of them is a near miss. For instance, note the "missing" transits of 1388, 1145, 0902, 0659, 0416, etc.. A useful way to organize the transits is by grouping them into series where each member of a series is separated by 88,756 days or 243 years (= sum of 8 + 105.5 + 8 + 121.5 years). Thus, the transits of 1518, 1761 and 2004 would belong to one series, while the transits of 1639, 1882 and 2125 would belong to another series. Such transit series are quite long-lived and may last 5,000 years or more. For example, Series 4 (December at Ascending Node) began in -1763 (1764 BCE) and will run through 2854 (a grazing transit) for a total of 20 transits spanning 4617 years. These transit families are quite analogous to the Saros series for solar and lunar eclipses. The position of the orbital nodes of Venus with respect to Earth are slowly changing with time. Five thousand years ago, transits occurred around May 21 and November 19. At present, the transits occur within a day of June 7 and December 9. In about 1500 years, the transits will occur during Earth's solstices (June 21 and December 22). This trend in the shift of transit dates is readily apparent in the catalog below. Over a period of approximately eighty thousand years, the transit dates will migrate forward one complete cycle through the seasons. All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

27/39

The following catalog contains predictions for every transit of Venus during the six thousand year interval 2000 BCE through 4000 CE. The information for each transit in the catalog is summarized as follows. The calendar date6 and geocentric Universal Time7 of the four transit contacts8 and the instant of greatest transit9 are found in the first six columns. The Sun's coordinates (Right Ascension and Declination) and the Greenwich Sidereal Time at 00:00 UT are given next. The minimum separation between the centers of Venus and the Sun is listed in arc-seconds. Finally the transit series10 is given. The individual columns in each table are described in greater detail in the Key to Transit Catalogs. Over the six millennium period of this catalog, transits of Venus can be organized into six series. The transits in any one series recur with a 243 year period. The series numbers have been assigned in chronological order with respect to the first transit in each series. Transit series with an odd number occur at Venus' descending node (May/June) while series with an even number occur at Venus' ascending node (November/December). All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

28/39

Transit Contact Times (UT) ------------------------------------I II Greatest III IV h:m h:m h:m h:m h:m

Date

Minimum Sep. "

Sun RA h

Sun Dec °

GST h

Transit Series

-1998 -1892 -1884 -1763 -1755 -1649 -1641 -1520 -1512 -1406 -1398 -1277 -1269 -1163 -1155 -1034 -1026

Nov May May Nov Nov May May Nov Nov May May Nov Nov May May Nov Nov

18 21 19 20 18 22 20 20 18 23 20 21 19 23 21 21 19

10:03 18:33 11:22 23:46 10:42 23:41 16:13 23:14 11:04 04:53 20:39 22:37 11:36 10:05 01:26 22:27 12:03

10:20 18:53 11:40 11:00 00:03 16:29 23:49 11:23 05:19 20:55 23:02 11:58 10:41 01:42 22:48 12:30

13:49 21:42 14:44 00:56 14:17 02:32 19:48 01:17 14:23 07:18 00:23 01:18 14:35 12:00 05:19 01:30 14:33

17:19 00:31 17:49 17:35 05:00 23:06 02:45 17:22 09:17 03:51 03:33 17:13 13:19 08:56 04:12 16:36

17:36 00:50 18:06 02:06 17:52 05:22 23:23 03:20 17:42 09:44 04:07 03:58 17:35 13:54 09:11 04:34 17:03

374.0 617.5 545.4 966.6 474.8 696.9 459.9 871.8 585.4 780.4 384.6 760.3 684.5 858.1 295.9 665.6 796.4

14.541 2.721 2.581 14.831 14.669 2.872 2.732 14.961 14.797 3.024 2.883 15.090 14.928 3.177 3.036 15.223 15.058

-15.31 16.16 15.50 -16.65 -15.91 16.83 16.20 -17.21 -16.48 17.47 16.86 -17.74 -17.04 18.08 17.50 -18.25 -17.58

2.672 14.885 14.739 2.966 2.810 15.035 14.889 3.104 2.946 15.185 15.038 3.241 3.084 15.334 15.189 3.378 3.221

2 1 3 4 2 1 3 4 2 1 3 4 2 1 3 4 2

-0920 -0912 -0791 -0783 -0669 -0548 -0540 -0426 -0305 -0183 -0062

May May Nov Nov May Nov Nov May Nov May Nov

23 21 21 19 22 21 19 22 22 22 22

15:40 05:52 21:49 12:37 10:24 21:28 14:46 20:41 18:56 20:09

06:07 22:08 13:17 10:39 21:46 15:01 20:58 19:11 20:25

16:40 09:50 01:13 14:28 14:25 01:07 14:05 18:50 00:32 23:00 00:07

13:32 04:19 15:38 18:12 04:28 22:38 04:06 02:49 03:49

17:39 13:47 04:38 16:18 18:26 04:45 22:53 04:22 03:03 04:05

942.2 222.1 553.1 899.2 137.4 451.2 1012.3 61.5 335.5 11.0 229.8

3.332 3.190 15.355 15.190 3.345 15.489 15.322 3.502 15.623 3.659 15.759

18.67 18.11 -18.74 -18.10 18.69 -19.21 -18.59 19.25 -19.66 19.76 -20.08

15.484 15.338 3.515 3.358 15.489 3.652 3.495 15.639 3.789 15.788 3.926

1 3 4 2 3 4 2 3 4 3 4

0060 May 22 0181 Nov 22 0303 May 24

23:05 19:18 03:06

23:19 19:33 03:21

03:07 23:21 07:06

06:55 03:08 10:52

07:10 03:24 11:06

87.4 114.3 157.7

3.817 15.895 3.977

20.25 -20.48 20.71

15.938 4.063 16.088

3 4 3

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Transit Contact Times (UT) ------------------------------------I II Greatest III IV h:m h:m h:m h:m h:m

Date

Minimum Sep. "

Sun RA h

Sun Dec °

GST h

Transit Series

0424 0546 0554 0667 0789 0797 0910

Nov May May Nov May May Nov

22 24 22 23 24 22 23

18:41 07:18 03:26 18:07 11:25 06:33 17:26

18:56 07:33 18:22 11:40 07:10 17:42

22:45 11:14 04:34 22:10 15:16 08:24 21:25

02:34 14:56 01:58 18:51 09:37 01:09

02:49 15:11 05:43 02:14 19:07 10:15 01:24

9.6 232.3 933.6 99.2 307.6 866.6 207.9

16.033 4.138 3.990 16.172 4.300 4.151 16.312

-20.86 21.13 20.72 -21.21 21.52 21.14 -21.53

4.200 16.238 16.093 4.338 16.389 16.243 4.475

4 3 5 4 3 5 4

1032 1040 1153 1275 1283 1396 1518 1526 1631 1639 1761 1769 1874 1882

May May Nov May May Nov May May Dec Dec Jun Jun Dec Dec

24 22 23 25 23 23 25 23 07 04 06 03 09 06

15:19 10:03 16:48 19:04 13:08 15:45 22:29 16:15 03:52 14:57 02:02 19:15 01:49 13:57

15:35 10:30 17:05 19:20 13:31 16:02 22:46 16:35 04:59 15:15 02:20 19:34 02:19 14:17

19:04 12:25 20:41 22:40 15:48 19:27 01:57 19:12 05:19 18:26 05:19 22:25 04:07 17:06

22:33 14:20 00:18 02:01 18:05 22:52 05:08 21:49 05:40 21:36 08:18 01:16 05:56 19:55

22:49 14:46 00:34 02:17 18:28 23:09 05:25 22:09 06:47 21:55 08:37 01:35 06:26 20:15

373.4 791.8 307.6 444.9 733.6 424.3 505.3 666.7 939.3 523.6 570.4 609.3 829.9 637.3

4.463 4.314 16.454 4.627 4.477 16.595 4.791 4.640 16.912 16.738 4.957 4.805 17.056 16.881

21.87 21.52 -21.83 22.18 21.87 -22.10 22.45 22.18 -22.64 -22.34 22.69 22.44 -22.82 -22.56

16.539 16.393 4.613 16.689 16.543 4.750 16.838 16.692 5.045 4.888 16.988 16.842 5.182 5.025

3 5 4 3 5 4 3 5 6 4 3 5 6 4

2004 2012 2117 2125 2247 2255 2360 2368 2490 2498 2603 2611 2733

Jun Jun Dec Dec Jun Jun Dec Dec Jun Jun Dec Dec Jun

08 05 10 08 11 09 12 10 12 10 15 13 15

05:13 22:10 23:58 13:15 08:42 01:08 22:32 12:29 11:39 03:48 20:43 12:04 15:02

05:33 22:27 00:21 13:38 09:03 01:25 22:52 13:00 12:02 04:05 21:02 13:07 15:30

08:20 01:30 02:48 16:01 11:33 04:38 01:44 14:45 14:17 07:25 00:13 13:34 17:18

11:07 04:32 05:15 18:24 14:04 07:51 04:35 16:31 16:32 10:45 03:25 14:01 19:06

11:26 04:49 05:38 18:48 14:25 08:08 04:56 17:01 16:55 11:02 03:43 15:04 19:34

626.9 554.4 723.6 736.4 691.3 491.9 625.7 836.4 741.1 442.7 517.1 934.8 808.3

5.121 4.969 17.201 17.026 5.289 5.135 17.348 17.172 5.454 5.301 17.494 17.319 5.623

22.89 22.68 -22.97 -22.74 23.05 22.87 -23.09 -22.90 23.17 23.02 -23.18 -23.03 23.24

17.137 16.991 5.320 5.163 17.287 17.141 5.458 5.301 17.436 17.290 5.596 5.440 17.587

3 5 6 4 3 5 6 4 3 5 6 4 3

You may see these ones

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Date

Transit Contact Times (UT) ------------------------------------I II Greatest III IV h:m h:m h:m h:m h:m

Minimum Sep. "

Sun RA h

Sun Dec °

GST h

Transit Series

2741 2846 2854 2976 2984

Jun Dec Dec Jun Jun

13 16 14 16 14

06:33 19:30 17:45 09:01

06:49 19:47 18:19 09:16

10:17 23:11 12:19 19:44 12:49

13:44 02:35 21:10 16:22

14:00 02:52 21:44 16:37

385.6 432.1 1026.7 850.5 336.3

5.468 17.643 17.466 5.791 5.634

23.14 -23.24 -23.12 23.28 23.21

17.440 5.735 5.578 17.735 17.589

5 6 4 3 5

3089 3219 3227 3332 3462 3470 3575 3705 3713 3818 3956

Dec Jun Jun Dec Jun Jun Dec Jun Jun Dec Jun

18 19 17 20 21 19 23 24 21 25 23

17:39 20:50 11:21 16:16 23:29 13:31 14:29 15:25 12:57 17:22

17:55 21:46 11:37 16:32 13:46 14:44 15:40 13:12 17:37

21:31 22:19 15:13 20:14 00:27 17:26 18:32 02:32 19:22 17:01 21:21

01:06 22:52 18:50 23:56 21:07 22:19 23:05 20:50 01:06

01:23 23:48 19:05 00:12 01:26 21:22 22:34 23:20 21:05 01:21

320.6 908.1 293.4 235.5 948.1 247.9 131.5 989.3 215.2 41.1 175.2

17.790 5.957 5.801 17.939 6.123 5.967 18.087 6.289 6.133 18.237 6.300

-23.27 23.28 23.25 -23.26 23.24 23.25 -23.23 23.16 23.21 -23.16 23.13

5.873 17.885 17.738 6.012 18.034 17.887 6.150 18.182 18.036 6.290 18.184

6 3 5 6 3 5 6 3 5 6 5

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Key to Catalogs of Transits of Venus Catalogs of transit circumstances include the following data. The calendar date1 and geocentric Universal Time2 of the four transit contacts3 and the instant of greatest transit4 are found in the first six columns. The Sun's coordinates (Right Ascension and Declination) and the Greenwich Siderial Time at 00:00 UT are given next. The minimum separation between the centers of the planet and the Sun is listed in arc-seconds. Finally the transit series5 is given. Transits recur in cycles much like the Saros cycle for eclipses: • Over the seven century period of the Mercury catalog, transits can be organized into twelve series.

The transits in any one series recur with a 46 year period (16,802 days). The series numbers have been assigned in chronological order with respect to the first transit in each series. • Over the four millennium period of the Venus catalog, transits can be organized into six series. The transits in any one series recur with a 243 year period (88,757 days). The series numbers have been assigned in chronological order with respect to the first transit in each series. Col Heading 1 Date 2

I

3

II

4 5

Greatest Transit III

6

IV

7

Minimum Sep. Sun RA Sun Dec GST Transit Series

8 9 10 11

Definition/Description Calendar Date (Gregorian) at instant of Greatest Eclipse. (Julian calendar is used before 1582 Oct 15). Contact I is the instant when the planet's disk is externally tangent to the Sun (transit begins). Contact II is the instant when the entire disk of the planet is first internally tangent to the Sun. The period from contact I to II is called Ingress.) Universal Time (UT) of Greatest Transit, which is defined as the instant when the planet passes closest to the center of the Sun as seen from the center of Earth. Contact III is the instant when the planet reaches the opposite limb of the Sun and is once again internally tangent to the Sun. Contact IV is the instant when the planet's disk is externally tangent to the Sun. (transit ends) The period from contact III to IV is called Egress.) The minimum angular separation between centers of the Sun and planet cccurs at the instant of greatest transit. Geocentric Right Ascension of the Sun at greatest transit (hours). Geocentric Declination of the Sun at greatest transit (degrees). Greenwich Siderial Time at 00:00 UT. Recurrance series of transit. Mercury transits recur after an interval of 46 years. Venus transits recur after an interval of 243 years.

Calendar Dates The Julian calendar is used for all dates up to 1582 Oct 04. After that date, the Gregorian calendar is used. Due to the Gregorian Calendar reform, the day after 1582 Oct 04 (Julian calendar) is 1582 Oct 15 (Gregorian calendar). Note that Great Britain did not adopt the Gregorian calendar until 1752. For more information, see Julian and Gregorian Calendars.

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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The Julian calendar does not include the year 0, so the year 1 BCE is followed by the year 1 CE. This is awkward for arithmetic calculations. In this catalog, dates are counted using the astronomical numbering system which recognizes the year 0. Historians should note the numerical difference of one year between astronomical dates and BCE dates. Thus, the year 0 corresponds to 1 BCE, and year -100 corresponds to 101 BCE, etc.. (See: Year Dating Conventions ) There is some historical uncertainty as to which years from 43 BCE to 8 CE were counted as leap years. For the purposes of this catalog, we will assume that all Julian years divisible by 4 will be counted as leap years.

Visibility of Transits To determine whether a transit is visible from a specific geographic location, it is simply a matter of calculating the Sun's altitude and azimuth during each phase of the transit. The calculations can be performed on any pocket calculator having trig functions (SIN, COS, TAN). Armed with the latitude and longitude of the location, the transit catalog provides all the additional information needed to make the calculations. For the equations and an example of how to calculate the Sun's altitude for a specific location, see Transit Visibility. As an aid to historical research, two Excel 97 spreadsheet files have been prepared which perform the above calculations automatically. You simply enter the location name, latitude and longitude. Each of the tables then calculates the altitude of the Sun at that location for every contact for several dozen of transits. The two tables are similar but cover different time periods: Please note that these files will not open properly unless you have Excel 97 (or newer) installed on your computer. When each of the spreadsheets is downloaded, it will be opened automatically in Excel where you will be able to enter the coordinates of any geographic location to calculate the transit circumstances. The spreadsheets are protected so that you can not accidently delete or edit any information required by the calculations. Only the name and coordinates of the geographic location (in the green box of each spreadsheet) may be modified. The transit times in these tables are based of geocentric calculations. Because of parallax, the observed transit times for any given location may differ by up to 10 minutes. Furthermore, the Sun's actual altitude at a location may differ by up to 2 degrees from the tables. Such precision is adequate for many applications especially since the geocentric approximation greatly simplifies the circumstances calculations. A final source of time and altitude uncertainty in transits before 0001 CE is due to variations in Earth's rotation which is expressed through the parameter delta T.

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Footnotes The terms BCE and CE are abbreviations for "Before Common Era" and "Common Era," respectively. They are the secular equivalents to the BC and AD dating conventions (See:Year Dating Conventions ) The descending node is the point along a planet's orbit where it crosses the ecliptic (Earth's orbital plane) from north to south. The ascending node is the point along a planet's orbit where it crosses the ecliptic (Earth's orbital plane) from south to north. Aphelion is the most distant point from the Sun along a planet's elliptical orbit. Perihelion is the closest point from the Sun along a planet's elliptical orbit. The Julian calendar is used for all dates up to 1582 Oct 04. After that date, the modern Gregorian calendar is used. Due to the Gregorian Calendar reform, the day after 1582 Oct 04 (Julian calendar) is 1582 Oct 15 (Gregorian calendar). Note that Great Britain did not adopt the Gregorian calendar until 1752. For more information, see Julian and Gregorian Calendars. For most practical purposes, Universal Time (UT) is equivalent to Greenwich Mean Time (GMT). The four transit contact times are defined as follows: • Contact I - The instant when the planet's disk is externally tangent to the Sun (transit begins). • Contact II - The entire disk of the planet is first seen when the planet is internally tangent to the Sun. • Contact III - The planet reaches the opposite limb and is once again internally tangent to the Sun. • Contact IV - The planet's disk is externally tangent to the Sun (transit ends). Contacts I and II define the phase called ingress while contacts III and IV are known as egress. Greatest transit is defined as the instant when the planet passes closest to the center of the Sun as seen from the center of Earth. The value for delta-T was determined as follows: 1) pre-1600: delta T was calculated from empirical expressions by Stephenson [1997] 2) 1600-present: delta T was obtained from published observations 3) future: delta-T was extrapolated from current values

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Venus Fact Sheet Venus/Earth Comparison

Bulk parameters Mass (1024 kg) Volume (1010 km3) Equatorial radius (km) Polar radius (km) Volumetric mean radius (km) Ellipticity (Flattening) Mean density (kg/m3) Surface gravity (eq.) (m/s2) Surface acceleration (eq.) (m/s2) Escape velocity (km/s) GM (x 106 km3/s2) Bond albedo Visual geometric albedo Visual magnitude V(1,0) Solar irradiance (W/m2) Black-body temperature (K) Topographic range (km) Moment of inertia (I/MR2) J2 (x 10-6) Number of natural satellites Planetary ring system

Venus 4.8685 92.843 6051.8 6051.8 6051.8 0.000 5243. 8.87 8.87 10.36 0.3249 0.750 0.65 -4.40 2613.9 231.7 15. 0.33 4.458 0. No

Earth Ratio (Venus/Earth) 5.9736 0.815 108.321 0.857 6378.1 0.949 6356.8 0.952 6371.0 0.950 0.00335 0.0 5515. 0.951 9.80 0.905 9.78 0.907 11.19 0.926 0.3986 0.815 0.306 2.45 0.367 1.77 -3.86 1367.6 1.911 254.3 0.911 20. 0.750 0.3308 0.998 1082.63 0.004 1. No

Orbital parameters Semimajor axis (106 km) Sidereal orbit period (days) Tropical orbit period (days) Perihelion (106 km) Aphelion (106 km) Synodic period (days) Mean orbital velocity (km/s) Max. orbital velocity (km/s) Min. orbital velocity (km/s) Orbit inclination (deg) Orbit eccentricity Sidereal rotation period (hrs) Length of day (hrs) Obliquity to orbit (deg)

Venus 108.21 224.701 224.695 107.48 108.94 583.92 35.02 35.26 34.79 3.39 0.0067 -5832.5 2802.0 177.36

Earth 149.60 365.256 365.242 147.09 152.10 29.78 30.29 29.29 0.00 0.0167 23.9345 24.0000 23.45

Ratio (Venus/Earth) 0.723 0.615 0.615 0.731 0.716 1.176 1.164 1.188 0.401 243.686 116.750 (0.113)

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Venus Observational Parameters Discoverer: Discovery Date:

Unknown Prehistoric

Distance from Earth Minimum (106 km) 38.2 Maximum (106 km) 261.0 Apparent diameter from Earth Maximum (seconds of arc) 66.0 Minimum (seconds of arc) 9.7 Maximum visual magnitude -4.6 Mean values at inferior conjunction with Earth Distance from Earth (106 km) 41.44 Apparent diameter (seconds of arc) 60.2

Venus Mean Orbital Elements (J2000) Semi major axis (AU) Orbital eccentricity Orbital inclination (deg) Longitude of ascending node (deg) Longitude of perihelion (deg) Mean Longitude (deg)

0.72333199 0.00677323 3.39471 76.68069 131.53298 181.97973

North Pole of Rotation Right Ascension: Declination : Reference Date :

272.76 67.16 12:00 UT 1 Jan 2000 (JD 2451545.0)

Venus Atmosphere Surface pressure: Surface density: Scale height: Total mass of atmosphere: Average temperature: Diurnal temperature range: Wind speeds: Mean molecular weight:

92 bars ~65. kg/m3 15.9 km ~4.8 x 1020 kg 737 K (464 C) ~0 0.3 to 1.0 m/s (surface) 43.45 g/mole

Atmospheric composition (near surface, by volume): Major: 96.5% Carbon Dioxide (CO2), 3.5% Nitrogen (N2) Minor (ppm): Sulfur Dioxide (SO2) - 150; Argon (Ar) - 70; Water (H2O) - 20; Carbon Monoxide (CO) - 17; Helium (He) - 12; Neon (Ne) - 7

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Acknowledgments Transit predictions were generated on a Macintosh G4 iBook using algorithms developed from the Explanatory Supplement [1974] and Meeus [1989]. All transit calculations are by Fred Espenak, and he assumes full responsibility for their accuracy. Besselian elements for the transit predictions are from "Transits" by Jean Meeus (Willmann-Bell, 1989). This is an indispensable reference for anyone wishing to do transit calculations. The 2004 transit predictions were generated on an Apple G4 iMac computer using algorithms developed from Meeus [1989] and the Explanatory Supplement [1974]. Ephemerides for the Sun and Venus were generated from VSOP87. The author wishes to thank Goddard's Living with a Star program for support of this work. All calculations, diagrams, tables and opinions presented in this paper are those of the author and he assumes full responsibility for their accuracy. Special thanks to National Space Club summer intern Lauren Williams for her hard work and valuable assistance in preparing the web version of this paper. (July 2003) Special thanks to eclipse chaser Michael Gill for enthusiastically and rigorously beta-testing this page and for catching typographic errors. (2003 March)

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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References (Transit Predictions) • • • • • • •

Explanatory Supplement to the Astronomical Ephemeris and the American Ephemeris and Nautical Almanac, 1974, Her Majesty's Nautical Almanac Office, London. Macdonald , P., 2002, "The transit of Venus on 2004 June 8", J. Brit. Astr. Assoc., 112, 6, pp 319-324. Maor, E., 2000, June 8, 2004--Venus in Transit, Princeton University Press, Princeton. Meeus, J., 1956,"Transits of Mercury, 1920 to 2080", J.B.A.A., 67, 30. Meeus, J., 1958,""Transits of Venus, 3000 BC to AD 3000", J.B.A.A., 68, 98. Meeus, J., 1989, Transits, Willmann-Bell, Inc., Richmond. Newcomb, S., 1895,"Tables of the Motion of the Earth on its Axis Around the Sun", Astron. Papers Amer. Eph., Vol. 6, Part I.

References (History of Transits) • •

• •

• • •

• •

• • •

• •

Berry, Arthur. "A Short History of Astronomy" (1898) Good general information. Includes detailed description of 1761-69 transits. Chapman, Allan. "Jeremiah Horrocks, the Transit of Venus, and the 'New Astronomy' in early seventeenth-century England". Qtrly. J. Royal Astr. Soc, 31 (1990) pp 333-357. An appraisal of Horrocks' achievement; an attempt to dispel some myths which surround him, and a discussion of his methods. Ferris, Timothy "Coming of Age in the Milky Way", esp. pp 130-135 A very readable account of 17th century attempts to use the transit of Venus to measure the solar parallax. Gaythorpe, S.B. "Horrocks Observations of the Transit of Venus 1639 November 24 (O.S.)". J.Brit.Astr.Assoc., 47 (1936-7) pp 60-68. This paper gives a detailed quantitative account of Horrocks' observations and the circumstances in which they were made. Halley, Edmond. "A new Method of determining the Parallax of the Sun" (Phil.Trans., Royal Soc., Vol xxix, 1716 pp 454-464) Hetherington, Barry. "An Astronomical Anniversary: The Transit of Venus 1769 June 3". J.Brit.Astr.Assoc., 80 (1969) pp 52-53. A short summary of various expeditions. Horrocks, Jeremiah. "Venus in sole visa" (1662) translated as "The Transit of Venus over the Sun" and published in "Memoir of the Life and Labors of the Rev.Jeremiah Horrox" by Rev.A.B.Whatton (London, 1859) Maor, Eli. "June 8, 2004 - Venus In Transit", (1999) Princeton University Press. An excellent account of the history of transit expeditions and their historical importance to astronomy. Maunder, Michael and Moore, Patrick . "Transit: When Planets Cross the Sun", (1999) Springer-Verlag. Another excellent account of the history of transit expeditions with details not covered in Maors' book. Includes practical information on observing transits. Newcomb, S., 1898,"Transits of Mercury, 1677-1881", Astron. Papers Amer. Eph., Vol. 6, Part IV. Pannekoek, Anton. "A History of Astronomy" (1961) Good general information. Includes detailed description of 1761-69 transits. Porter, J.G. "Transits of Mercury and Venus". J.Brit.Astr.Assoc., 80 (1970) pp 183-189. A very useful discussion of the theory of transits, with some reference to Halley's method of determining the solar parallax. Ruddy, H.E. "The Transit of Venus, 1874". J.Brit.Astr.Assoc., 64 (1954) pp 304-309. A diary style account of the expedition of Lt. C.Corbet to Kerguelen Island. Westfall, Richard S. "Jeremiah Horrocks" + "Edmond Halley". Internet, Galileo Project. Key facts relating to these two astronomers. Useful bibliographies.

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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Links on Transits • • • • • • • • • • • • • • • • • •

Seven Century Catalog of Mercury Transits: 1600 CE to 2300 CE - Espenak, NASA/GSFC Six Millennium Catalog of Venus Transits: 2000 BCE to 4000 CE - Espenak, NASA/GSFC The 1999 Transit of Mercury - Fred Espenak, NASA/GSFC The 2003 Transit of Mercury - Fred Espenak, NASA/GSFC The 2004 Transit of Venus - Fred Espenak, NASA/GSFC The 2004 and 2012 Transits of Venus - Fred Espenak, NASA/GSFC World Visibility Map of 2004 Transit of Venus (PDF) - Astronomical Almanac 2004 Transit Times for Major World Cities (PDF) - Astronomical Almanac Geometry of Transits - "The Quest for the Solar Parallax" David Sellers Frequency of Transits - Peter M Langford The 1761 & 1769 Transits of Venus - Richard W. Pogge/Ohio State University The 1882 Transit of Venus - W.P. Koorts ([email protected]) 2004 Transit of Venus - NASA - Sun/Earth Connection 2004 Transit of Venus - Chuck Bueter Public Outreach Project for 2004 Transit - ESO & EAAE 2004 Transit of Venus - Paper Plate Education Future Transits of Venus - Eclipse99, Guernsey Transit of Venus - Excellent List of Links - Chuck Bueter

All calculations and diagrams presented in this section are those of the author and he assumes full responsibility for their accuracy. "Transit Predictions by Fred Espenak, NASA/GSFC"

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