# Biggest object in a solar system sky? **URL:** \ **Category:** Factual Questions\ **Created:** [January 12, 2010, 2:45am UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608 "2010-01-12T02:45:40Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Sapo](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Sapo](https://boards.straightdope.com/u/Sapo)\ **Post date:** [January 12, 2010, 2:45am UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/1 "2010-01-12T02:45:40Z")
The Sun from Mercury? Jupiter from one of its moons? What is the biggest object you can see on the sky standing on the surface of a solar system body? How big does it look? ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [January 12, 2010, 3:00am UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/2 "2010-01-12T03:00:18Z")
> [@Sapo](#): > > The Sun from Mercury? Jupiter from one of its moons? What is the biggest object you can see on the sky standing on the surface of a solar system body? How big does it look? Probably the Milky Way seen from any planet in the Solar System if you count that as an object. The sun as seen from Mercury is only about three times as big as it is seen from Earth. ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [January 12, 2010, 3:13am UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/3 "2010-01-12T03:13:03Z")
Mars takes up 39 degrees when viewd from Phobos. Jupiter takes up 19 degrees when viewed from Io. Saturn takes up 36.5° as viewed from Mimas. Uranus takes up 22° as seen from Miranda. Neptune takes up 22° as seen from Nereid. Pluto takes up 7° as seen from Charon. The sun takes up 1.6° as seen from Mercury. [Solar System Simulator](http://space.jpl.nasa.gov/) There might be some minor moon of Jupiter or saturn that puts all these numbers to shame, but the simulator doesn’t cover those. ---
**Author:** ![MikeS](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@MikeS](https://boards.straightdope.com/u/MikeS)\ **Post date:** [January 12, 2010, 4:42am UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/4 "2010-01-12T04:42:50Z")
> [@Squink](#): > > There might be some minor moon of Jupiter or saturn that puts all these numbers to shame, but the simulator doesn’t cover those. [ul][_]Jupiter from the surface of [Metis](http://en.wikipedia.org/wiki/Metis_(moon)) takes up a whopping 68 degrees of the sky. [_] Saturn as viewed from [Pan](http://en.wikipedia.org/wiki/Pan_(moon)) takes up about 54 degrees of the sky. [_]Uranus viewed from [Cordelia](http://en.wikipedia.org/wiki/Cordelia_(moon)) takes up about 62 degrees of the sky. [_]Neptune as viewed from [Naiad](http://en.wikipedia.org/wiki/Naiad_(moon)) takes up about 62 degrees of the sky.[/ul] Looks like Metis is the winner, at least among the named moons. ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [January 12, 2010, 5:07am UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/5 "2010-01-12T05:07:06Z")
> [@MikeS](#): > > Looks like Metis is the winner, at least among the named moons. There might be another contender among the binary asteroids. It looks to me like one component of [90 Antiope](http://en.wikipedia.org/wiki/90_Antiope) would cover 37°+ of sky when viewed from the other component. ---
**Author:** ![BwanaBob](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bwanabob/32/2985_2.png) [@BwanaBob](https://boards.straightdope.com/u/BwanaBob)\ **Post date:** [January 12, 2010, 2:57pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/6 "2010-01-12T14:57:57Z")
In what way is 37 degrees bigger than 68 degrees (Jupiter from Metis)? ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [January 12, 2010, 3:09pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/7 "2010-01-12T15:09:14Z")
> [@BwanaBob](#): > > In what way is 37 degrees bigger than 68 degrees (Jupiter from Metis)? Just saying there’s a good possibility that there’s some double asteroid with a view matching or exceeding that from Metis. Of course, 90° is the limit, and the Metis view is getting close to that. ---
**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\ **Post date:** [January 12, 2010, 4:09pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/8 "2010-01-12T16:09:23Z")
> [@Squink](#): > > Just saying there’s a good possibility that there’s some double asteroid with a view matching or exceeding that from Metis. Of course, 90° is the limit, and the Metis view is getting close to that. Um… Isn’t 180° the limit? Earth fills 143° of the ISS’ sky, but I don’t suppose there are any natural solar system bodies with orbits that low. ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [January 12, 2010, 4:19pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/9 "2010-01-12T16:19:59Z")
> [@naita](#): > > Um… Isn’t 180° the limit? Yeah, it is. I plead morning stupidity. ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [January 12, 2010, 4:28pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/10 "2010-01-12T16:28:43Z")
Wouldn’t there be a practical limit for a natural object of less than 180° – specifically, whatever the visual measurement would be for an object orbiting its primary just outside Roche’s limit? ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [January 12, 2010, 4:41pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/11 "2010-01-12T16:41:25Z")
> [@Polycarp](#): > > Wouldn’t there be a practical limit for a natural object of less than 180° – specifically, whatever the visual measurement would be for an object orbiting its primary just outside Roche’s limit? I am pretty sure the Roch limit is for fairly big and/or fragile things. Small bodies can orbit all the way down the atmosphere/surface. ---
**Author:** ![Alka\_Seltzer](https://avatars.discourse-cdn.com/v4/letter/a/c89c15/32.png) [@Alka\_Seltzer](https://boards.straightdope.com/u/Alka_Seltzer)\ **Post date:** [January 12, 2010, 4:51pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/12 "2010-01-12T16:51:31Z")
Yes, artificial satellites aren’t pulled apart by tidal forces. Binary asteroid somewhere might be a good guess. ---
**Author:** ![Skammer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/skammer/32/143_2.png) [@Skammer](https://boards.straightdope.com/u/Skammer)\ **Post date:** [January 12, 2010, 4:55pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/13 "2010-01-12T16:55:49Z")
> [@billfish678](#): > > I am pretty sure the Roch limit is for fairly big and/or fragile things. > > Small bodies can orbit all the way down the atmosphere/surface. I’m orbiting the earth at its surface right now! And in case you’re interested, it occupies 180° of my view. ---
**Author:** ![RedSwinglineOne](https://avatars.discourse-cdn.com/v4/letter/r/a9adbd/32.png) [@RedSwinglineOne](https://boards.straightdope.com/u/RedSwinglineOne)\ **Post date:** [January 12, 2010, 5:31pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/14 "2010-01-12T17:31:54Z")
Saturn’s rings from Saturn? ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [January 12, 2010, 5:37pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/15 "2010-01-12T17:37:33Z")
> [@Skammer](#): > > I’m orbiting the earth at its surface right now! And in case you’re interested, it occupies 180° of my view. If your are standing up it aint 🙂 ---
**Author:** ![Sapo](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Sapo](https://boards.straightdope.com/u/Sapo)\ **Post date:** [January 12, 2010, 5:37pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/16 "2010-01-12T17:37:49Z")
> [@Squink](#): > > Mars takes up 39 degrees when viewd from Phobos. > Jupiter takes up 19 degrees when viewed from Io. > Saturn takes up 36.5° as viewed from Mimas. > Uranus takes up 22° as seen from Miranda. > Neptune takes up 22° as seen from Nereid. > Pluto takes up 7° as seen from Charon. > The sun takes up 1.6° as seen from Mercury. > > [Solar System Simulator](http://space.jpl.nasa.gov/) > > There might be some minor moon of Jupiter or saturn that puts all these numbers to shame, but the simulator doesn’t cover those. Awesome link and very cool that the winner was Mars and not some bigger body. Until, that is, they mentioned Jupiter from Metis. Big hog cannot leave some records for other planets. I don’t think I was considering binary asteroids when I posted the OP but they are an interesting case. ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [January 12, 2010, 5:55pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/17 "2010-01-12T17:55:55Z")
> [@Skammer](#): > > I’m orbiting the earth at its surface right now! And in case you’re interested, it occupies 180° of my view. Go to the bottom of a deep valley and you can beat that. Or a well. 🙂 ---
**Author:** ![Bearflag70](https://avatars.discourse-cdn.com/v4/letter/b/8e7dd6/32.png) [@Bearflag70](https://boards.straightdope.com/u/Bearflag70)\ **Post date:** [January 12, 2010, 6:19pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/18 "2010-01-12T18:19:55Z")
> [@Squink](#): > > Uranus takes up 22° as seen from Miranda. > [@MikeS](#): > > Uranus viewed from [Cordelia](http://en.wikipedia.org/wiki/Cordelia_(moon)) takes up about 62 degrees of the sky. ::snort:: ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [January 12, 2010, 8:05pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/19 "2010-01-12T20:05:12Z")
> [@Bearflag70](#): > > ::snort:: No goatse jokes, please! 😃 ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [January 12, 2010, 8:15pm UTC](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608/20 "2010-01-12T20:15:51Z")
No wonder our solar system sucks. Look how few bodies are willing to give even a 100 degrees, much less 110 degrees. I miss that old “can do work hard” solar system I used to know. [Next page](https://boards.straightdope.com/t/biggest-object-in-a-solar-system-sky/524608.md?page=2)