Jupiter and Ganymede in exquisite detail

By Phil Plait | October 7, 2011 1:32 pm

If you go outside shortly after sunset and face east, you’ll see a brilliant white "star" madly shining down on you. That’s no star: it’s Jupiter, king of the planets, the brightest object in the sky right now after the Sun and the Moon. Now is the best time to observe it, since the Earth is placed directly between the giant planet and the Sun, meaning we’re as close to it as we’ll get all year.

"Amateur" astronomer Emil Kraaikamp took advantage of the situation, and, with his friend Rik ter Horst — who crafted his own 40 cm (16") mirror telescope — took this amazing shot of Jupiter:

[Click to enjovianate.]

I found this image on the Astron/Jive image of the day page (you should really subscribe to their RSS feed), and Emil gave me permission to use it here. Isn’t it lovely? The level of detail is quite incredible, about as good as you can possibly get with a 40 cm ‘scope. They used a video camera to capture a lot of frames, and then pick the best ones to add together. Earth’s atmosphere roils and shifts, causing images to blur out, so this technique compensates for that — and Jupiter obliges by being very bright, allowing for lots of short exposures in rapid succession.

The little guy below Jupiter and to the right is the moon Ganymede, which, if Jupiter weren’t there, would be considered a planet in its own right. It’s the biggest moon in the solar system, and actually comfortably larger than Mercury — though also much less massive, because Mercury has lots of iron, while Ganymede is mostly rock and ice. It’s incredible that advances in technology have made it possible to capture such detail on an object 600 million km (360 million miles) away! The image on the right of Ganymede is a NASA map of the moon based on space probe images, showing that those features Emil and Rik captured are real.

Emil tells me it’s been cloudy where he is lately, which is too bad. It’s been touch-and-go here with the weather, but seeing this is making me think of hauling out my own ‘scope and taking a look. I should get on that before the snow starts to fall here in Boulder…

In the meantime, check out the Related posts links below to see more of Emil’s amazing work.

Related posts:

Jupiter rolls into view
Saturn rages from a billion kilometers away
The blue clouds of the red planet [Must see animation of clouds on Mars!]

CATEGORIZED UNDER: Astronomy, Pretty pictures

Comments (12)

  1. Funny thing you posted this right as I am processing some images taken last night. Only have an 8″ here though. The seeing was great for a while, BUT there was a REAL heavy fog out. Here is an image with a quick process of three images from last night:


  2. Pat

    Ganymede is the reason Jupiter is covered with storms. If Jupiter exposes itself to Ganymede one more time, it’s out of the solar system.

  3. Wow, awesome. Makes me want to build my own 16″ mirror telescope!

  4. Bill

    So where’s the photo of the homemade telescope!? :)

  5. DLC

    There used to be articles in the old Astronomy and Science magazines on how to grind your own telescope. It seems to me that it was fairly straightforward, if a bit detailed.
    Some cool pics for a couple of “Amateurs” — in this sense unpaid professionals .

  6. From another forum, here is a pic of the scope that they used:


  7. Bigfoot

    The weather here is of no concern. No matter how good the terrestrial seeing conditions are, I swear it’s ALWAYS cloudy on Jupiter!

  8. MadScientist

    [OT] Here’s a case of some truly Bad Astronomy (and bad history as well as bad anthropology):


    The article is just loaded with bunkum like “NASA Technology” to measure the position of rocks (GPS? – but *why* – GPS is not even necessary to get the information needed to make the claims made). Then some nonsense on how it was only recently demonstrated that Australian Aborigines could count beyond 5 or 6. It looks like this Ray Norris is legit though – he seems to work as a radio astronomer for Australia’s public scientific research organization and self-publishes cuckoo ideas (which he also promotes on his employer’s website).

  9. Scott Kardel

    What is the ring-like feature at ~2 o’clock on Jupiter? It doesn’t look like any oval/storm feature that I have ever seen on Jupiter.

  10. Infinite123Lifer

    I Love Ganyemde! Not because I have any clue what it is but because every time I see the word my brain goes GAWN EEE MAAA DEEEE! Thats probably not how its pronounced but I don’t wanna help it. It is a great name.

    So Ganymede is a mercury-ish size moon around Jupiter and also its largest satellite. Very cool.

    Enjovianate. Ok. I have a 100 year old Webster Dictionary, 1911. Well more on that later perhaps.

    Doing a lil research on the Ganymede I just started looking for enunciation. I got:
    Ganymede (play /ˈɡænɨmiːd/)[12] is a satellite of Jupiter.

    Oh, the woes of being phonetically challenged.

    On the other hand I think it would make for a great story to actually have some vastly superior alien race completely hidden to us under all those clouds.


  11. Holy cow — that picture was taken with a ground-based 40 cm scope? How is that even possible?

  12. Scott: that Ring like feature is called Oval BA, or also referred to as Red Spot Jr.

    A couple of things to note about that image, South is Up in that image. Also Ganymede is also at a different scale.

    For a comparison of Jupiter and Ganymede at the same scale, check out the image in this thread:


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