Did I see another planet?



A couple days ago, I zoomed in with my 30x optical zoom camera, and after some exposure adjustments, a bright star in the night sky turned into this:

Bright star with (planets)?

Are those other planets or other stars? Or is that a lens effect?

EDIT: The bright object in question was ~60 degrees above the horizon, and ESE of me (East-south-east). I took the picture on 3-25-16 from Madison, Wisconsin.

EDIT: Question answered, more clear picture added FYI.

More clear pic - Enjoy!


Posted 2016-03-27T13:27:32.133

Reputation: 198

2That should be Jupiter and his 4 Galilean moons. However on your picture 2 of them seem missing, maybe they were cut-off by the field-of-view. – AtmosphericPrisonEscape – 2016-03-27T13:42:12.813

14Sometimes they hang out behind the planet. – Wayfaring Stranger – 2016-03-27T14:36:54.060

@AtmosphericPrisonEscape you should submit that as an answer, I found that to be correct with a quick look at an app :) I will accept that immediately – Bobdabiulder – 2016-03-27T14:52:59.993


Cross-posted to Astronomy and Photography. Please don't do that. It's against site policy because it fragments answers and wastes people's time when they write an answer to something that's already been answered elsewhere.

– David Richerby – 2016-03-27T17:53:51.807

@DavidRicherby Sorry D: – Bobdabiulder – 2016-03-27T20:47:24.370

1Very nice picture, by the way. – Russell Borogove – 2016-03-28T02:21:11.663

7@WayfaringStranger: Sometimes they also hang out in front of the planet, at which point they're equally invisible to this type of equipment. – Michael Seifert – 2016-03-28T14:57:26.710

@RusselBorogrove thanks :) – Bobdabiulder – 2016-03-28T20:57:01.443

1Jupiter And His Four Galilean Moons - sounds like a 50's band. :-) – Bob Jarvis – 2016-03-28T23:39:46.130

@BobJarvis Agreed – Bobdabiulder – 2016-03-29T02:16:10.097

Past answers were enough, but i wanted to add: It is extremely difficult for you to find another planet. If you don't have an incredibly expensive telescope it is really difficult to see even the other ones discovered by the telescopes in orbit around the sun past Pluto, or even Pluto itself. Planets orbiting around the stars all mostly discovered by passage, because the stars are way too bright and far, so an extremely little but regular decrease in intensity over a line usually tells that there is a planet orbiting around that stars. Other technologies like radio waves could also do, but s – MarkWuji – 2016-03-29T13:37:51.843

@MarkWuji you are forgetting that phones exist, and apps show you where they are... – Bobdabiulder – 2016-03-29T21:09:48.977



You don't say what time you were looking. Here is a screenshot from Stellarium at 10pm Wisconsin time on 25th March 2016. Jupiter is in the ESE, but the altitude is a bit lower than 60 degrees. Seems fairly conclusive. You were seeing Ganymede and a Europa/Io combination.


Rob Jeffries

Posted 2016-03-27T13:27:32.133

Reputation: 50 656

9:20 was the timestamp on the picture – Bobdabiulder – 2016-03-27T20:46:40.787

Another picture shows this clearly, check the latest edit to the question – Bobdabiulder – 2016-03-27T20:53:21.423


That should be Jupiter and his 4 Galilean moons.

They are usually very well visible even with very cheap equipment and a nice experience for amateur astronomy. On your picture 2 of them seem missing, maybe they were cut-off by the field-of-view, or possibly as a commenter pointed out, they might be behind the planet.
You can test that notion actually, as Io runs around Jupiter pretty fast and can show significant movement relative to the planet on a timespan of ~2-3 hours (a typical observing session). So if after 2 hours another 'diamond' appears behind Jupiter, you can be pretty sure it to be the volcanic moon Io.


Posted 2016-03-27T13:27:32.133

Reputation: 3 483

The moon in front of Jupiter is strangely sharp. Do you think that has to do with the software in the camera, or is it a real optical effect? – LocalFluff – 2016-03-27T16:07:17.387

1@LocalFluff: Wouldn't bet my eye on it if the moons differ in sharpness... But I'd say it could be related to the contrast, which decreases for the moon closer in. That should wash out dimmer features and thus make it appear sharper. So in that sense I'd speculate on a real, measurable effect. – AtmosphericPrisonEscape – 2016-03-27T16:19:55.647


@LocalFluff Jupiter looks overexposed. That causes blurriness. The dimmer moons are likely better exposed, so fewer photons in the wrong image sensor cell to blur things up: https://en.wikipedia.org/wiki/Image_sensor

– Wayfaring Stranger – 2016-03-27T17:44:56.507


This appears to be Jupiter and two of its four "Galilean" moons, being the four discovered by Galileo with his telescope in 1610. I searched with Wolfram Alpha (http://www.wolframalpha.com/input/?i=jupiter+moon+configuration+march+25th+2016+9pm+US+central+time) to try and determine which moons you were looking at, and the answer was quite interesting.

Callisto was too close to Jupiter (as viewed from Earth) to be seen in your image. The outermost object is definitely Ganymede, and the other object appears to be a combination of Europa and Io, as these were very close (again, as viewed from Earth), so much so that they appear as one object in the image. Hope this helps.

Screenshot of WolframAlpha results


Posted 2016-03-27T13:27:32.133

Reputation: 293

8Wolfram never ceases to surprise me. +1'd – Mindwin – 2016-03-28T19:13:11.210

@Mindwin Same lol – Bobdabiulder – 2016-03-29T02:15:53.233