Help Shape the Future of Space Exploration

Join The Planetary Society Now  arrow.png

Join our eNewsletter for updates & action alerts

    Please leave this field empty

Headshot of Emily Lakdawalla

Spotting Jupiter's Moons...with a Solar Telescope!?

Posted by Emily Lakdawalla

06-04-2011 12:27 CDT

Topics: Jupiter's moons, Ganymede, the Sun, Callisto, solar observing spacecraft, Jupiter

It's not uncommon to see planets wandering through the field of view of a solar telescope, and when it's a bright planet like Jupiter it's almost painfully obvious. But I was astounded to learn this morning that SOHO can not only see Jupiter, it can actually resolve Jupiter's moons (at least its two outer ones) as points of light separate from their planet! That's just plain cool.

Here's an animation composed of one day's worth of SOHO images, roughly one frame per hour. SOHO's LASCO camera actually gathers images at about five times that frame rate, but this was enough detail to see the motion. It would've been cool if there were a major solar prominence that day, but it seems to have been a relatively quiet day on the Sun; there's something interesting happening at about the 4:30 position but the most prominent activity in this animation is the rapid motion of Jupiter across the frame.

SOHO's view of the Sun and Jupiter, April 5, 2011


SOHO's view of the Sun and Jupiter, April 5, 2011
SOHO's view of the Sun on April 5, 2011 also contained Jupiter near its solar conjunction, lower left.

And here's an animation of the full-resolution data, zoomed in on Jupiter. There's various noise and background stars moving about, but just to the left and right of Jupiter, just above and below the "wings" of saturated pixels streaking to the left and right, you can see two tiny little dots that move in a steady fashion from left to right. The left-hand one is Ganymede; the right-hand one is Callisto. These are the outermost of Jupiter's moons, so Io and Europa must also be within view, but are lost in the glare of the planet.

Spotting Jupiter's moons with a solar camera

NASA / ESA / SOHO / animation by Emily Lakdawalla

Spotting Jupiter's moons with a solar camera
As SOHO monitored the Sun on April 5, 2011, Jupiter was passing through its field of view. SOHO's LASCO camera was able to resolve two of Jupiter's moons as points of light separate from the blazing "star" of their planet. Ganymede is to the left of Jupiter, and Callisto is to the right. Both appear to move from left to right over the course of the 23 hours of this animation.

Thanks to @SungrazerComets for the tip!

See other posts from April 2011


Or read more blog entries about: Jupiter's moons, Ganymede, the Sun, Callisto, solar observing spacecraft, Jupiter


Leave a Comment:

You must be logged in to submit a comment. Log in now.
Facebook Twitter Email RSS AddThis

Blog Search


Our Curiosity Knows No Bounds!

Become a member of The Planetary Society and together we will create the future of space exploration.

Join Us

Featured Images

Gullies in the rim of a volcanic vent, Copland crater, Mercury
Asteroid 2008 EV5
Asteroid Redirect Mission spacecraft
Ready to launch
More Images

Featured Video

Intro Astronomy 2015. Class 8: Galilean Satellites, Saturn System

Watch Now

Space in Images

Pretty pictures and
awe-inspiring science.

See More

Join the New Millennium Committee

Let’s invent the future together!

Become a Member

Connect With Us

Facebook! Twitter! Google+ and more…
Continue the conversation with our online community!