05/28/2018 – Ephemeris – NASA’s Juno spacecraft takes deep dives at Jupiter

Ephemeris for Memorial Day, Monday, May 28th. Today the Sun will be up for 15 hours and 15 minutes, setting at 9:17, and it will rise tomorrow at 6:02. The Moon, 1 day before full, will set at 6:24 tomorrow morning.

NASA’s Juno spacecraft has made 11 close passes of Jupiter since being inserted into Jovian orbit in July 2016. It has a highly elliptical orbit. It comes in over the north pole, passes only 2,000 miles over the cloud tops at the equator and heads out over the south pole, avoiding the most intense parts of Jupiter’s radiation belts. The high latitude and polar clouds appear more chaotic than expected. We can’t see these very well from the Earth. The magnetic field is much stronger and lumpier than thought before. A very much improved and complex picture of our largest planet is emerging, as we expected. The mission isn’t over and years of analysis are ahead to begin to more fully understand the solar system’s greatest planet.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addenda

Chaotic storms at Jovian high latitudes. Credit NASA/JUNO

Jupiter’s North Pole in the infrared. 8 cyclones surrounding a 9th at the pole. Credit: NASA/JPL-Caltech/SwRI/ASI/INAF/JIRAM

Jupiter’s South Pole in the infrared. 5 cyclones surrounding a 6th at the pole. Credit: NASA/JPL-Caltech/SwRI/ASI/INAF/JIRAM

Alan Bean

Astronaut Alan Bean, 4th person to walk on the Moon with Apollo 12 passed away this weekend.  He also commanded the second Skylab mission and retired to become an artist, a painter of his adventures on the Moon and in space.  Of the twelve men who walked on the Moon, only four survive.

04/11/2017 – Ephemeris – What’s under Jupiter’s cloud tops?

Ephemeris for Tuesday, April 11th.  The Sun will rise at 7:04.  It’ll be up for 13 hours and 17 minutes, setting at 8:22.  The Moon, at full today, will rise at 8:54 this evening.

I made an error in yesterday’s on-air program which I fixed before posting this blog version.  The moon Io will be over the face of Jupiter from when it rises tonight until 8:58 p.m.*, thereafter it will be seen just to the west of the planet.  What we see of Jupiter are its cloud tops.  Planetary astronomers have some very educated guesses as to what lies beneath them.  An atmosphere of mainly hydrogen and helium, ending in a hot liquid ocean of hydrogen.  Beneath that a core of metallic hydrogen that generates the planet’s huge magnetic field.  Below that maybe a core of solid iron and other metals.  NASA’s Juno spacecraft now orbiting Jupiter is tasked with finding out the interior structure by measuring the velocity of the spacecraft as it flies just above the cloud tops of this giant planet.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

* Observers in other locations around the world can check out the table from yesterday’s post of other Jovian satellite events after this entry is posted at 4:01 UT, April 11, 2017.

Addendum

Jupiter and its moons in a telescope at 10 p.m. both April 10th & 11th, 2017. Created using Cartes du Ciel (Sky Charts).

For a year’s worth of Jovian satellite events and when the Great Red Spot crosses Jupiter’s central meridian, go to: http://www.projectpluto.com/jevent.htm.

The Juno spacecraft. Credit: NASA.

A February 2, 2017 Juno image of Jupiter’s south pole and its chaotic storm clouds. I think I have a paisley tie that looks like that. Credit NASA/JPL-Caltech/SwRI/MSSS/John Landino.