Transit of Earth from Jupiter

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A transit of Earth across the Sun as seen from Jupiter takes place when the planet Earth passes directly between the Sun and Jupiter, obscuring a small part of the Sun's disc for an observer on Jupiter. During a transit, Earth can be seen from Jupiter as a small black disc moving across the face of the Sun.

The event is particularly interesting because both the Earth and the Moon can usually be seen together in transit. In rare cases one of them transits and the other does not, such as on December 21, 2060, when there is a grazing transit for the Moon and a near-miss for the Earth. In other cases, the two may be so close together that they are hard to tell apart, such as on June 24, 2055, when the Earth and Moon are less than 20" apart as seen from Jupiter.

Naturally, no one has ever seen a transit of Earth from Jupiter, nor is this likely to happen in any foreseeable future. Nevertheless, the next one will take place on July 9, 2008.

A transit could hypothetically be observed from the surface of one of Jupiter's moons rather than from Jupiter itself. The times and circumstances of the transits would naturally be slightly different.

The Earth-Jupiter synodic period is 398.883 days. It can be calculated using the formula 1/(1/P-1/Q), where P is the sidereal orbital period of Earth (365.25636 days, not the same as a tropical year) and Q is the orbital period of Jupiter (4332.71 days).

Transits of Earth from Jupiter repeat with a pattern of 83 years. That is, the December/January transits recur in a pattern of 12, 12, 12, 47 years, and the June/July transits do likewise.

Note: the images linked to in the following table do NOT take into account the finite speed of light. The distance of Earth from Jupiter at inferior conjunction is approximately 4.2 AU, which would correspond to about 33 light-minutes. It can take up to 12 hours for Earth to transit across the Sun at its widest point, thus the images correspond fairly closely to what would actually be seen by an observer on Jupiter.

The images correspond to a hypothetical observer at the center of Jupiter. Since Jupiter has a very large radius, the parallax of Earth between Jupiter's center and its north or south pole would be about 23.5", which is about 5.5 times Earth's apparent angular diameter of 4.2", or about 6.0% of the Sun's angular diameter (about 6.5'). Therefore, some extremely close near-misses might be seen as grazing transits at Jupiter's poles.

Near misses are indicated with strikeout.

Transits of Earth from Jupiter
January 1, 2002	[1]
July 9, 2008	[2]
January 5, 2014	[3]
July 13, 2020	[4]
January 10, 2026	[5]
June 24, 2055	[6]
December 21, 2060	[7]
June 29, 2067	[8]
December 26, 2072	[9]
July 4, 2079	[10]
December 31, 2084	[11]
July 9, 2091	[12]
January 4, 2097	[13]
July 15, 2103	[14]
January 10, 2109	[15]

[edit] See also

• Astronomical transit

Transit visibility from planets superior to the transiting body
Venus	Earth	Mars	Jupiter	Saturn	Uranus	Neptune
Mercury	Mercury	Mercury	Mercury	Mercury	Mercury	Mercury
	Venus	Venus	Venus	Venus	Venus	Venus
		Earth	Earth	Earth	Earth	Earth
			Mars	Mars	Mars	Mars
				Jupiter	Jupiter	Jupiter
					Saturn	Saturn
						Uranus

[edit] References

• Albert Marth, Note on the Transit of the Planet Mars and its Satellites across the Sun’s disc, which will occur for the Planet Jupiter and its Satellites on April 13, 1886, Monthly Notices of the Royal Astronomical Society, 46 (1886), 161–164. [16]
• Andrew Crommelin, Ephemeris for physical observations of Jupiter, 1901, Monthly Notices of the Royal Astronomical Society, 61 (1900), 117–118 [17] (full article: [18])

[edit] External links

• JPL Solar System Simulator