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05/11/2017 – Ephemeris – Cassini is surviving its death-defying dives under the rings of Saturn
Ephemeris for Thursday, May 11th. Today the Sun will be up for 14 hours and 40 minutes, setting at 8:59, and it will rise tomorrow at 6:17. The Moon, 1 day past full, will rise at 9:42 this evening.
The Cassini spacecraft has been redirected by passing Titan on a special trajectory that sent it into a fatal set of orbits that take it a few thousand miles above Saturn’s cloud tops and under the innermost rings. So far after two passes Cassini survives. One discovery of the first pass was a storm, perhaps a hurricane, whose clear eye is at Saturn’s north pole. Cassini has yet to turn its cameras to the rings on these passes inside the rings, but it will before its final orbit. Currently it is flying communication dish first to protect its delicate instruments from ring particles. So far the gap between the rings and the planet are more free of particles than expected. Which is a good omen for the last 20 passes between the rings and planet.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
In its planned last 22 orbits of Saturn, the Cassini spacecraft will pass between the innermost ring and the planet itself. Credit NASA, JPL.
The clearing (blue sky) in the clouds at Saturn’s north pole spotted by Cassini on its first pass under the rings. Credit: NASA/JPL-Cal Tech/S Si/Sophia Nasr
07/19/2013 – Ephemeris – Smile you’re on Candid Cassini Camera
Ephemeris for Friday, July 19th. Today the sun will be up for 15 hours and 6 minutes, setting at 9:21. The moon, 3 days before full, will set at 3:55 tomorrow morning. Tomorrow the sun will rise at 6:16.
Between 5:27 and 5:42 p.m. today go outside and look to the southeast and smile. An hour and a half later when the light arrives the Cassini spacecraft, hiding from the sun behind Saturn will take a series of photographs that will include the Earth in the background. All of us, the Earth included will fit into one pixel in Cassini’s camera. This is a reprise of the famous back-lit photograph of Saturn taken earlier in its mission. Closer to home members of the Grand Traverse Astronomical Society will be part of Kingsley Heritage Days Saturday and Sunday to view the sun if it’s clear. Also the society will host a star party at the NMC’s Rogers Observatory starting at 9 p.m. tomorrow night.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Saturn night side mosaic taken early in the mission. Note the pale blue dot at the 9:30 position outside the main rings and just inside the next fuzzy ring out. That’s Earth. Credit: NASA. Click on the image to enlarge.
Bob Moler's Ephemeris Blog 