Transit of Mars from Saturn

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

Naturally, no one has ever seen a transit of Mars from Saturn, nor is this likely to happen in any foreseeable future. Nevertheless, the next one will take place on May 17, 2008.

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

The Mars-Saturn synodic period is 733.893 days. It can be calculated using the formula 1/(1/P-1/Q), where P is the sidereal orbital period of Mars (686.98 days) and Q is the orbital period of Saturn (10746.940 days).

Coincidentally, this is only about 3 days more than a calendar year on Earth. Interestingly, transits are empirically observed to occur in pairs exactly 16 Earth years apart, usually to the day.

The inclination of Mars's orbit with respect to Saturn's ecliptic is 2.36°, which is greater than its value of 1.85° with respect to Earth's ecliptic.

Note: the images linked to in the following table do NOT take into account the finite speed of light. The distance of Mars from Saturn at inferior conjunction is approximately 8.0 AU or about 66 light-minutes. It can take up to 10 hours for Mars 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 Saturn.

The images correspond to a hypothetical observer at the center of Saturn. Since Saturn has a large radius, the parallax of Mars between Saturn's center and its north or south pole would be about 10.4", which is about 8.5 times Mars's apparent angular diameter of 1.2", or about 4.5% of the Sun's angular diameter (about 3.5'). Therefore, some extremely close near-misses might be seen as grazing transits at Saturn's poles.

Near misses are indicated with strikeout.

Transits of Mars from Saturn
June 26, 1612	[1]
August 19, 1640	[2]
October 5, 1654	[3]
October 5, 1670	[4]
November 28, 1684	[5]
January 13, 1729	[6]
March 2, 1743	[7]
March 2, 1759	[8]
June 10, 1817	[9]
July 28, 1831	[10]
July 27, 1847	[11]
November 5, 1905	[12]
December 22, 1919	[13]
December 22, 1935	[14]
April 1, 1994	[15]
May 17, 2008	[16]
May 17, 2024	[17]
August 26, 2082	[18]
October 11, 2096	[19]
October 12, 2112	[20]
January 21, 2171	[21]
March 7, 2185	[22]
March 9, 2201	[23]
June 17, 2259	[24]
August 2, 2273	[25]
August 2, 2289	[26]
November 12, 2347	[27]
December 28, 2361	[28]
December 28, 2377	[29]
February 20, 2406	[30]
March 29, 2420	[31]
April 7, 2436	[32]
May 23, 2450	[33]
May 24, 2466	[34]

[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 Earth and Moon across the Sun’s Disk as seen from Mars on November 12, 1879, and on some kindred Phenomena, Monthly Notices of the Royal Astronomical Society, 39 (1879), 513–514. [35]

[edit] External links

• JPL Solar System Simulator