Transit of Venus from Saturn
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A transit of Venus across the Sun as seen from Saturn takes place when the planet Venus passes directly between the Sun and Saturn, obscuring a small part of the Sun's disc for an observer on Saturn. During a transit, Venus 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 Venus from Saturn, nor is this likely to happen in any foreseeable future. Nevertheless, the next one will take place on May 6 2012.
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 Venus-Saturn synodic period is 229.494 days. It can be calculated using the formula 1/(1/P-1/Q), where P is the sidereal orbital period of Venus (224.695434 days) and Q is the orbital period of Saturn (10746.940 days).
The inclination of Venus's orbit with respect to Saturn's ecliptic is 2.06°, which is less than its value of 3.39° 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 Venus from Saturn at inferior conjunction is approximately 8.8 AU or about 73 light-minutes. It can take up to 10 hours for Venus 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 Venus between Saturn's center and its north or south pole would be about 9.4", which is about 4.7 times Venus's apparent angular diameter of 2.0", 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.
The transit that occurred on March 21 1894 was particularly interesting, because during the transit of Venus from Saturn there was simultaneously a transit of Mercury from Saturn and a transit of Mercury from Venus.
Also interesting is the event of December 8 2056, when there is a simultaneous near-miss of Venus and Mercury.
Near misses are indicated with strikeout.
| Transits of Venus from Saturn | |
|---|---|
| March 21 1894 | [1] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=0&vbody=6&month=3&day=21¢ury=18&decade=9&year=4&hour=23&minute=0&fovmul=1&rfov=0.25&bfov=0.25&porbs=1)
[2] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=1&vbody=2&month=3&day=21¢ury=18&decade=9&year=4&hour=23&minute=0&fovmul=1&rfov=3&bfov=3&porbs=1) |
| | [3] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=0&vbody=6&month=9&day=20¢ury=20&decade=1&year=1&hour=5&minute=0&fovmul=1&rfov=0.25&bfov=0.25&porbs=1) |
| May 6 2012 | [4] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=0&vbody=6&month=5&day=6¢ury=20&decade=1&year=2&hour=13&minute=0&fovmul=1&rfov=0.25&bfov=0.25&porbs=1) |
| December 21 2012 | [5] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=0&vbody=6&month=12&day=21¢ury=20&decade=1&year=2&hour=20&minute=0&fovmul=1&rfov=0.25&bfov=0.25&porbs=1) |
| | [6] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=0&vbody=6&month=8&day=8¢ury=20&decade=1&year=3&hour=0&minute=0&fovmul=1&rfov=0.25&bfov=0.25&porbs=1) |
| | [7] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=0&vbody=6&month=5&day=29¢ury=20&decade=2&year=7&hour=17&minute=0&fovmul=1&rfov=0.25&bfov=0.25&porbs=1) |
| January 14 2028 | [8] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=0&vbody=6&month=1&day=14¢ury=20&decade=2&year=8&hour=10&minute=0&fovmul=1&rfov=0.25&bfov=0.25&porbs=1) |
| August 31 2028 | [9] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=0&vbody=6&month=8&day=31¢ury=20&decade=2&year=8&hour=6&minute=0&fovmul=1&rfov=0.25&bfov=0.25&porbs=1) |
| | [10] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=0&vbody=6&month=4&day=18¢ury=20&decade=2&year=9&hour=2&minute=0&fovmul=1&rfov=0.25&bfov=0.25&porbs=1) |
| | [11] (http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=0&vbody=6&month=12&day=8¢ury=20&decade=5&year=6&hour=22&minute=0&fovmul=1&rfov=0.25&bfov=0.25&porbs=1) |
See also
Template:Transit visibility table
References
- Albert Marth, Note on the Transit of Mercury over the Sun’s Disc, which takes place for Venus on 1894 March 21, and on the Transits of Venus and Mercury, which occur for Saturn’s System on the same day, Monthly Notices of the Royal Astronomical Society, 54 (1894), 172–174. [12] (http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1894MNRAS..54..172M)
External links
- JPL Solar System Simulator (http://space.jpl.nasa.gov/)