Transit of Mercury from Saturn

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A transit of Mercury across the Sun as seen from Saturn takes place when the planet Mercury passes directly between the Sun and Saturn, obscuring a small part of the Sun's disc for an observer on Saturn. During a transit, Mercury 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 Mercury from Saturn, since nobody has ever been to Saturn. Nor is one likely to be seen in the foreseeable future. However, and unobserved one happened on September 27, 2012.

It is possible that a transit of Mercury could be observed from the surface of one of Saturn's moons rather than from Saturn itself. The times and circumstances of the transits would be slightly different.

The Mercury-Saturn synodic period is about 88.694 days. This can be calculated using the formula synodic period = 1/(1/P - 1/Q), where P is the sidereal orbital period of Mercury (87.968 days) and Q is the orbital period of Saturn (10746.940 days).

The inclination of Mercury's orbit with respect to Saturn's ecliptic is about 6.38 degrees, which is less than the inclination of about 7.00 degrees with respect to the ecliptic of the Earth.

The transits of Mercury as seen from Saturn are found to occur in clusters, with two such clusters happening every 30 years or so.

The transit that occurred on March 21, 1894 was a particularly interesting one because it happened on the same day as both transit a transit of Venus from Saturn and of a transit of Mercury from Venus. However, no two of these transits were simultaneous.

Also interesting will the transit of December 9, 2056, when Mercury barely misses transiting the Sun, but Venus begins an actual transit about six hours later.

Note: the image linked to in the following table does not take into account the finite speed of light. The distance of Mercury from Saturn at inferior conjunction is about 9.3 astronomical units or about 80 light-minutes. It will take about eight hours for Mercury to transit the face of the Sun, hence the image corresponds fairly closely to what would actually be seen by an observer on Saturn.

Transits of Mercury as seen from Saturn
March 4, 1998
June 1, 1998
August 28, 1998
November 25, 1998
February 21, 1999
December 30, 2011
March 28, 2012
June 25, 2012
September 27, 2012
July 22, 2027
October 19, 2027
January 15, 2028
April 13, 2028
July 10, 2028
August 15, 2041
November 12, 2041
February 9, 2042
March 7, 2057
June 3, 2057
August 31, 2057
November 28, 2057
January 2, 2071
April 1, 2071
June 29, 2071
September 26, 2071
July 25, 2086
October 22, 2086
January 18, 2087
April 17, 2087
May 22, 2100
August 19, 2100
November 16, 2100
February 13, 2101


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