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

Transits of Mercury from Mars are roughly twice as common as transits of Mercury from Earth: there are several per decade.

Transit
The Mars rovers Spirit and Opportunity could have observed the transit of January 12, 2005 (from 14:45 UTC to 23:05 UTC); however the only camera available for this had insufficient resolution. They were able to observe transits of Deimos across the Sun, but at 2' angular diameter, Deimos is about 20 times larger than Mercury's 6.1" angular diameter. Ephemeris data generated by JPL Horizons indicates that Opportunity would have been able to observe the transit from the start until local sunset at about 19:23 UTC, while Spirit could have observed it from local sunrise at about 19:38 UTC until the end of the transit.  The rover Curiosity observed the Mercury transit of June 3, 2014, marking the first time any planetary transit has been observed from a celestial body besides Earth.

The Mercury-Mars synodic period is 100.888 days. It can be calculated using the formula 1/(1/P-1/Q), where P is the orbital period of Mercury (87.969 days) and Q is the orbital period of Mars (686.98 days).

The inclination of Mercury's orbit with respect to that of Mars is 5.16°, which is less than its value of 7.00° with respect to Earth's ecliptic.

Transits 2000–2100

 December 18, 2003
 January 12, 2005
 November 23, 2005
 May 10, 2013
 June 3, 2014
 April 15, 2015
 October 25, 2023
 September 5, 2024 
 January 26, 2034 
 February 21, 2035
 July 13, 2044 
 May 24, 2045 
 November 8, 2052 
 December 3, 2053 
 October 14, 2054 
 April 25, 2063
 March 6, 2064
 July 27, 2073
 August 22, 2074
 December 17, 2082
 January 12, 2084
 November 22, 2084
 May 9, 2092
 June 3, 2093
 April 14, 2094

Simultaneous transits
The simultaneous occurrence of a transit of Mercury and a transit of Venus is extremely rare, but somewhat more frequent than from Earth, and will next occur in the years ,  and .
On several occasions a related event is predicted: a transit of Mercury and a transit of Venus, or transit of Earth, will follow themselves, one after the other, in an interval of only several hours.

On November 28, 3867, there will be a transit of Earth and Moon, and two days later there will be a transit of Mercury.
On January 16, 18551, transits of Mercury and Venus will occur 14 hours apart.

See also
 Astronomical transit
 Transit of Deimos from Mars
 Transit of Phobos from Mars
 Transit of Mercury from Earth

References

Sources
 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. 
 Giorgini, J.D., Yeomans, D.K., Chamberlin, A.B., Chodas, P.W., Jacobson, R.A., Keesey, M.S., Lieske, J.H., Ostro, S.J., Standish, E.M., Wimberly, R.N., "JPL's On-Line Solar System Data Service", Bulletin of the American Astronomical Society 28(3), 1158, 1996.

External links
 Transits of Mercury on Mars - Fifteen millennium catalog: 5 000 BC - 10 000 AD
 JPL Horizons

Transit of Mercury
Mars