Transit of Mars from Saturn
A '''[[astronomical transit|transit]] of [[Mars (planet)|Mars]] across the [[Sun]] as seen from [[Saturn (planet)|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 year|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.
<!-- cos i12 = sin i1 sin i2 cos (OM1 - OM2) * cos i1 cos i2 -->
{| border cellspacing=0 cellpadding=5 align="center"
!colspan="2"|Transits of Mars from Saturn
|-
| [[October 4]] [[1670]]
|-
| [[March 1]] [[1759]]
|-
| [[July 25]] [[1831]]
|-
| [[July 26]] [[1847]]
|-
| [[December 21]] [[1919]]
|-
| [[December 22]] [[1935]]
|-
| [[May 17]] [[2008]]
|-
| [[May 17]] [[2024]]
|-
| [[August 26]] [[2082]]
|-
| [[October 12]] [[2096]]
|-
| [[January 22]] [[2171]]
|-
| [[March 10]] [[2185]]
|-
| [[June 18]] [[2259]]
|-
| [[August 4]] [[2273]]
|-
| [[November 13]] [[2347]]
|-
| [[April 7]] [[2436]]
|-
| [[May 23]] [[2450]]
|-
|}
<!-- checked up to 2475 -->
==See also==
* [[Astronomical transit]]
{{transit visibility table}}
==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. [http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1879MNRAS..39..513M]
==External links==
* [http://space.jpl.nasa.gov/ JPL Solar System Simulator]
[[Category:Astronomical transits]]