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. Following the blue line to the left is the line of sight to Earth, while following the gray line to the left 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.
Orbital Motion
The graph below shows the positions of the four Galilean moons over the next 24 hours as seen from Earth. The curved lines show the path of each moon through time. The dark band in the center is Jupiter. The x-axis is the distance, in arc seconds, from the center of Jupiter:
At 0h UTC, Io begins the day at western elongation and will be moving into quad 4 headed east. Europa starts the day in quad 4 moving east pretty near Io from Earth's POV. Ganymede spends most of the day in quad 1 moving east. Callisto is in quad 1 moving east one more day.
At 6h UTC, Io is now firmly in quad 4 headed east.
By 12h UTC, Io and Europa are moving behind Jupiter.
By 18h UTC, Io and Europa are now firmly in quad 1 moving east. Ganymede is at eastern elongation and will be moving into quad 2 headed west.
At 0h UTC tomorrow, Io has gone through eastern elongation and is now in quad 2 headed west. Europa continues in quad 1 moving east for another half-day. Ganymede is now firmly in quad 2 moving west. Callisto spends its last full day in quad 1 moving east.
Apojoves and Perijoves
At 07:42 UTC, Io goes through a perijove (closest it will be to Jupiter this orbit) at a distance of 420,046.8 km. At 08:05 UTC, on the same side of the planet Europa goes through an apojove (furthest it will be to Jupiter this orbit) at a distance of 677,643.9 km. Europa is 1.613 times further away from Jupiter than Io.
Relative Positions and Motions
At 0h UTC, the position of Jupiter is RA 10h 33m 10.6s, DEC +10d 03m 56.4s. The phase angle continues to widen and today it's 1.972 degrees, which is 0.138 degrees greater than yesterday. Jupiter also continues to move away from the Sun at an angular separation of 10.614 degrees, which is 0.753 degrees greater than yesterday. The distance between Jupiter and Earth is 954,174,536.8 km, which is 417,968 km closer than yesterday. Jupiter and Earth are moving toward one another at a velocity of 17,415.33 km/h (similar to low Earth orbiting satellites) ad this is 1.294.1 km/h faster than yesterday. Jupiter is 806,559,462.3 km from the Sun, which is 35,649.4 km further away than yesterday. Jupiter and the Sun are moving apart at a velocity of 1,485.39 km/h, which is 0.26 km/h faster than yesterday.
Jupiter-Satellite Events
From 09:27 to 11:59 UTC, Io moves behind Jupiter. From 12:14 to 15:38 UTC, Europa moves behind Jupiter.
Orbital Ribbons
These are the spacial and temporal connections between the four Galilean moons. This is, once again, looking down upon the Jupiter system.
When is the first image of Jupiter after Superior Conjunction going to be taken? If you have one, send it to me!
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?
Subscribe at the right column of this blog and get these posts sent to you automatically!
Please send me your feedback, comments, and questions to jupitertoday AT gmail DOT com or the comments section of this blog.
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.
No comments:
Post a Comment