# Are satellites in permanent orbit? **URL:** \ **Category:** Factual Questions\ **Created:** [September 12, 2009, 8:06pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842 "2009-09-12T20:06:06Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![blood63](https://avatars.discourse-cdn.com/v4/letter/b/97f17d/32.png) [@blood63](https://boards.straightdope.com/u/blood63)\ **Post date:** [September 12, 2009, 8:06pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/1 "2009-09-12T20:06:06Z")
Are we safe from a rain of satellites or as they permanently fixed forever in Earth’s orbit. Will their velocities not slow with time due to minute particles of dust? ---
**Author:** ![cainxinth](https://avatars.discourse-cdn.com/v4/letter/c/7bcc69/32.png) [@cainxinth](https://boards.straightdope.com/u/cainxinth)\ **Post date:** [September 12, 2009, 8:07pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/2 "2009-09-12T20:07:17Z")
> **[Orbital decay](https://en.wikipedia.org/wiki/Orbital_decay)** > > Orbital decay is a gradual decrease of the distance between two orbiting bodies at their closest approach (the periapsis) over many orbital periods. These orbiting bodies can be a planet and its satellite, a star and any object orbiting it, or components of any binary system. If left unchecked, the decay eventually results in termination of the orbit when the smaller object strikes the surface of the primary; or for objects where the primary has an atmosphere, the smaller object burns, explodes, ... ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [September 12, 2009, 8:07pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/3 "2009-09-12T20:07:55Z")
At some point they will crash to Earth if not whisked away by a passing large mass. ---
**Author:** ![KneadToKnow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kneadtoknow/32/3999_2.png) [@KneadToKnow](https://boards.straightdope.com/u/KneadToKnow)\ **Post date:** [September 12, 2009, 8:14pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/4 "2009-09-12T20:14:33Z")
Since the OP did not specify artificial satellites, it is worth noting that the moon is actually [receding from the earth](http://eclipse.gsfc.nasa.gov/SEhelp/ApolloLaser.html). ---
**Author:** ![yabob](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yabob/32/2821_2.png) [@yabob](https://boards.straightdope.com/u/yabob)\ **Post date:** [September 12, 2009, 10:20pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/5 "2009-09-12T22:20:24Z")
You might be interested in the NASA Orbital Debris Program FAQ: [http://orbitaldebris.jsc.nasa.gov/faqs.html](http://orbitaldebris.jsc.nasa.gov/faqs.html) ---
**Author:** ![keeper0](https://avatars.discourse-cdn.com/v4/letter/k/b19c9b/32.png) [@keeper0](https://boards.straightdope.com/u/keeper0)\ **Post date:** [September 12, 2009, 10:40pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/6 "2009-09-12T22:40:41Z")
Nothing is permanent. Do you mean “Will they stay in orbit until the sun goes nova?” ---
**Author:** ![Danger\_Man](https://avatars.discourse-cdn.com/v4/letter/d/6de8d8/32.png) [@Danger\_Man](https://boards.straightdope.com/u/Danger_Man)\ **Post date:** [September 12, 2009, 11:10pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/7 "2009-09-12T23:10:07Z")
Short answer: Lower earth orbit satellites do fall down after some time and burn up in the atmosphere. Satellites above a certain altitude (including geostationary ones) will stay there pretty much permanently. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [September 12, 2009, 11:55pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/8 "2009-09-12T23:55:56Z")
Were you around in [1979](http://en.wikipedia.org/wiki/Skylab)? Read the “Abandonment and reentry” section. ---
**Author:** ![Dallas\_Jones](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dallas_jones/32/3277_2.png) [@Dallas\_Jones](https://boards.straightdope.com/u/Dallas_Jones)\ **Post date:** [September 13, 2009, 12:33am UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/9 "2009-09-13T00:33:00Z")
> [@keeper0](#): > > Nothing is permanent. Do you mean “Will they stay in orbit until the sun goes nova?” Our sun cannot go nova, it’s too small. It will expand and consume the earth, but that isn’t the same as a nova. ---
**Author:** ![blood63](https://avatars.discourse-cdn.com/v4/letter/b/97f17d/32.png) [@blood63](https://boards.straightdope.com/u/blood63)\ **Post date:** [September 14, 2009, 10:06pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/10 "2009-09-14T22:06:28Z")
> [@panache45](#): > > Were you around in [1979](http://en.wikipedia.org/wiki/Skylab)? Read the “Abandonment and reentry” section. Great Story! I was shingling a garage roof that day. Everyone was looking up because we knew Skylab was coming down but noone was sure where. My brother and I heard that debris was falling in Windsor, Ontario which is near our home. We were blown away. What are the chances? Later we found out the debris was from two planes colliding. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [September 15, 2009, 4:33am UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/11 "2009-09-15T04:33:36Z")
> [@Danger\_Man](#): > > Short answer: Lower earth orbit satellites do fall down after some time and burn up in the atmosphere. Satellites above a certain altitude (including geostationary ones) will stay there pretty much permanently. Even those will eventually decay. The key word there is eventually, since it will take a very long time for a geostationary satellite to decay. Figure thousands of years or more, though. ---
**Author:** ![kjckjc](https://avatars.discourse-cdn.com/v4/letter/k/e36b37/32.png) [@kjckjc](https://boards.straightdope.com/u/kjckjc)\ **Post date:** [September 15, 2009, 9:16am UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/12 "2009-09-15T09:16:14Z")
OT: What is the oldest satellite (man-made) that is still in use today? And, umm, what is it used for? ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [September 15, 2009, 3:59pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/13 "2009-09-15T15:59:33Z")
> [@kjckjc](#): > > OT: What is the oldest satellite (man-made) that is still in use today? And, umm, what is it used for? [Vanguard 1](http://en.wikipedia.org/wiki/Vanguard_1) is the oldest (51 years) piece still up there. It has an estimated orbital lifetime of 240 years. While it’s long dead, it can still be tracked by radar and is useful for long term data on orbital decay and the outer atmosphere. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [September 15, 2009, 4:04pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/14 "2009-09-15T16:04:54Z")
IIRC NASA purposely put up a satellite that was nothing more than a small, dense retro reflector. Small, dense, in a high orbit, its gonna be up there a LONG time, though I forget how long. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [September 15, 2009, 5:50pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/15 "2009-09-15T17:50:13Z")
> [@](#): > > Even those will eventually decay. The key word there is eventually, since it will take a very long time for a geostationary satellite to decay. Figure thousands of years or more, though. Think more like trillions. The Sun will engulf the Earth long before it happens. ---
**Author:** ![Measure\_for\_Measure](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/measure_for_measure/32/557_2.png) [@Measure\_for\_Measure](https://boards.straightdope.com/u/Measure_for_Measure)\ **Post date:** [September 17, 2009, 7:35pm UTC](https://boards.straightdope.com/t/are-satellites-in-permanent-orbit/509842/16 "2009-09-17T19:35:01Z")
> [@KneadToKnow](#): > > Since the OP did not specify artificial satellites, it is worth noting that the moon is actually [receding from the earth](http://eclipse.gsfc.nasa.gov/SEhelp/ApolloLaser.html). Those wanting to know why the moon’s orbit gets slightly larger each year can go here: > **[Lecture 20: Tides](https://www.astronomy.ohio-state.edu/pogge.1/Ast161/Unit4/tides.html)** Interesting stuff.