A transit of Phobos from Mars: <a href="https://en.wikipedia.org/wiki/Phobos_(moon)" class="extiw" title="w:Phobos (moon)">Phobos</a> is in transit across the Sun, as seen from Mars by MER <i>Opportunity</i> on March 10, 2004, at 07:36:38 UTC Earth time. In the photo, the Sun has angular diameter 20.5' while Phobos has angular diameter of 15.1'. <a href="https://en.wikipedia.org/wiki/Deimos_(moon)" class="extiw" title="w:Deimos (moon)">Deimos</a> by contrast usually has an angular diameter of about 2.3' as seen from Mars. Phobos took about 32 seconds to transit the Sun.
NASA/JPL/Cornell
2004-03-10
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