Jupiter Today | 03 August 2015 | Jupiter Hug

Good Day!

JUPITER TODAY is a daily blog about the dynamic Jupiter system for the purpose of monitoring activity.

We start with the overall view of activity with the Jupiter system, showing the orbits of the four Galilean moons:

This is a view of the Jupiter system looking down on it.  The blue line is the line of sight to Earth, while the gray line is the line of sight to the Sun.  The orbits of the four Galilean moons are shown.  The large dots indicate the position of each moon at 0h, 6h, 12h, 18h, and 24h (0h the next day) UTC for this date.  From this point of view, the moons revolve around Jupiter in a counter-clockwise motion.  For more information about this graphic, see the post from 30 July 2015.

At 0h UTC, Io begins the day just past eastern elongation and in quad 2 moving west.  Europa starts the day in quad 1 moving east.  Ganymede spends all day in quad 4 moving east along with Callisto.

By 6h UTC, Io is now firmly in quad 2 moving west.  Europa is near it eastern elongation and will be moving into quad 2 moving west.  So by about this time, the two inner Galilean moons are moving west, while the two outer Galilean moons are moving east.  All of them are moving towards Jupiter for a big group Hug.

At 12h UTC, Io has transited Jupiter and is now in quad 3 moving west.  Europa is past its eastern elongation and will spend the rest of the day in quad 2 moving west

By 18h UTC, Io is in quad 3 moving west but getting near its western elongation.

At 0h UTC tomorrow, Io is in quad 4 moving west.  Europa is still in quad 2 moving west and will soon be transiting Jupiter.  Ganymede is still in quad 4 moving east and will be moving behind Jupiter.  Callisto spends a few more hours in quad 4 when it too will appear to move behind Jupiter from Earth's point of view

At 10:06 UTC, Io goes through an apojove at a distance of 423,485.1 km.  Ganymede goes through an apojove (the furthest it will be in this orbit) at 17:08 UTC at a distance of 1,071,623.4 km.

Io transits Jupiter from 07:51 to 10:10 UTC.  That's a 133 minute transit.  Io shadow transits Jupiter from 08:14 to 10:32 UTC.

There are no satellite mutual events today.

A nice set of Orbital Ribbons today:

At 0h UTC, the position of Jupiter on Earth's celestial sphere is RA 10h 01m 49.3s, DEC +12d 58m 52.0s.  The phase angle today is 3.311 degrees, which is 0.134 degrees less than what it was yesterday.  The angular separation between Jupiter and the Sun as seen from Earth is 18.582 degrees, which is 0.744 degrees less than what it was yesterday.  The distance between Jupiter and the Sun is 805,166,728 km, which is 37,622 km further apart that yesterday.  This gives a radial velocity between Jupiter and the Sun of 1,567.6 km/h, which is 2.417 km/h slower than yesterday.  The distance between Jupiter and the Earth is 948,332,387 km, which is 746,584 km further apart than yesterday.  This gives a radial velocity between Jupiter and the Earth of 31,107.7 km/h, which is 1211.1 km/h slower than yesterday.

Even though Jupiter is near Superior Conjunction (taking place on 26 August 2015), please send me your pictures of Jupiter!  If you do, I'll post them to this blog!  Please also include the time (in UTC if possible) you took the image, the telescope you used, the camera you used, and any other information you might think is useful.

Spread the word about this daily blog!  This blog is subject to evolution.  What can I do to make this blog more interesting and more informative?

Please send me your feedback, comments, and questions to jupitertoday AT gmail DOT com.

With my gratitude, the data used to create the orbit plots and ribbons was supplied by the JPL Horizons website.  The graphics showing the location of the four moons as seen from Earth are via 'Jupiter Viewer 2.8'.  Jupiter-Satellite and Satellite mutual events data is supplied from IMCEE.

Until tomorrow, I bid you Peace.