Questions tagged [geostationary]

Questions about orbits whose position in the sky remains the same for a stationary observer on the primary body.

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37
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1answer
4k views

Are there any satellites in geosynchronous but not geostationary orbits?

I know there are a lot of geostationary satellites out there, but I'm wondering - are there any geosynchronous satellites that are not geostationary (ie - have a notable inclination to their orbit)?
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If we build a space elevator from Earth surface to GEO, could I step off it at GEO and remain in GEO?

Ignore for a moment the question of whether building such a space elevator is practical. Let's also ignore the minute delta-v involved in "stepping off" something in orbit. If we were to build a ...
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Name for geostationary orbit around another planet

A geostationary orbit is a circular orbit in Earth's equatorial plane whose rotation period matches that of the Earth. The "geo" in "geostationary" means Earth, so is there another term to designate ...
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How closely spaced are satellites at GEO?

As the picture below (kind of) shows, there are lots of satellites in geostationary orbit. Couple this with the fact that certain longitudes are more desirable than others (like above North America or ...
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How full is the geostationary belt?

The geostationary ring clearly seen in the above picture looks alarmingly crowded. How full is it? How much space does a satellite in that orbit require to operate safely? Surely, (other) ...
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What's salvageable from a dead satellite?

DARPA has proposed orbital maintenance and salvage robots. I had gathered a list of links that was lost when DARPA rearranged their website. But I was able to find this page: Phoenix Makes Strides in ...
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Why are obsolete geostationary satellites re-orbited above the geostationary belt?

That seems a bit counter-intuitive, because in an orbit above the belt, the satellite would eventually lose gain velocity, so its orbit would intersect the orbital plane of the geostationary ...
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Are any geosynchronous satellites visible with the naked eye?

It is very easy to spot LEO satellites during dusk or dawn. I am wondering if satellites further out in a geosynchronous orbit are also visible. Of course, if even possible, these would appear more ...
15
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What is the current cost per kg to send something into GSO/GEO?

I was reading this article and thought it was reasonably cheap, probably because I mistook LEO for GEO. What is the going rate to get something into GeoStationary Orbit and Geosynchronous Equatorial ...
14
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How many dead sats near GEO?

It's my understanding a geosynchronous satellite will put itself in a graveyard orbit just before it dies. How many dead sats are in GEO or in neighboring graveyard orbits? What is their total mass?
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Dangle a cable down to earth - fundamental Physics question

If I had the material that had the tensile strength, would it be possible to have it dangle from the lowest most practically possible geostationary object down into the atmosphere? Would it not ...
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How long does it take for a satellite to reach GEO?

Specifically for the SpaceX SES-8 mission going on right now. But, generally, how long does it take for a satellite to reach GEO at a minimum?
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What is the maximum mass of a satellite that can be placed in GEO?

What is the maximum mass of a satellite that can be placed in GEO? Or can satellites of any mass be placed in GEO?
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Why aren't space telescopes put in GEO?

I don't know of any space telescope that has been placed in geosynchronous orbit among the communication satellites. I wonder why not? In GEO, a space telescope could use a single stationary radio ...
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What is the reason for the Ariane 5 launcher with Intelsat 29e losing altitude?

After reaching a peak altitude of 222 km the Ariane 5 launcher with Intelsat 29e starts to lose altitude. What is the reason for this trajectory? Youtube video Paper on Ariane 5
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Are commercial communications satellites in GEO being constantly monitored by telescopes?

I was trying to look up GOES-17 in Spaceflight101 but got sidetracked in the search result and ended up reading this thread about AMC-9, which links to the YouTube video Rough cut video of AMC-9 ...
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Tethered geostationary orbit

One of the biggest issues that I've heard of in building a space elevator is the high tensile strength of the cord used to tether the the elevator to the ground. If there's a structure that's at ...
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413 views

Is it feasible to pump fuel into orbit?

Imagine a huge fuel depot in geostationary orbit. Suppose further that it is tethered to the Earth and that there's a large hose snaking down all the way. Is it feasible to pump fuel up 35,786km? Can ...
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How is the launch window decided for GTO launches?

What launch vehicle, spacecraft and target orbit parameters decide the time of launch to GTO for satellites destined for GEO? The target orbital slot is always in the same relative position to the ...
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1answer
877 views

How much is a geostationary satellite expected to deviate from the geostationary orbit?

I've read this already and some Wikipedia articles, but found no real estimates on how much does a satellite deviate from its standard location. Say that the standard sub-satellite point (SSP) is <...
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1answer
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Do geosynchronous satellite launches require a tight launch window?

I thought only launches to rendezvous (resupply, repair, space station expansion etc) and direct launches into interplanetary trajectory require precisely timed launch window. Then I read: Geosync ...
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How much “wobble” does a typical geostationary satellite experience?

Recall that geostationary satellites are placed into an orbit which is designed to stay above a fixed point on the Earth's surface. If the Earth and the satellite were both spherical cows in an ...
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Are there any CubeSats that have been launched into Geostationary (GEO/GSO) or Geostationary Transfer Orbit (GTO)?

There is one mission by GSFC/NASA - Shields-1 to be launched into GTO. Apart from that I couldn't find any other mission to GTO/GEO. It would be of great help if there is any information on this.
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Thrust and rotation strategy to circularize a standard GTO orbit using ion propulsion?

The previous question How much time does it take to circularize a GTO orbit using ion propulsion? has a good, quantitative answer based on a known delta-v. But I'm wondering how would you actually ...
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What kind of liquid propulsion systems do GEO satellites use?

Coming from a question about distances between satellites in GEO, what liquid propulsion systems do a majority of GEO satellites carry to maintain their slot positions? It is easy to find information ...
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Could an areostationary satellite help locate asteroids?

Could NASA put an artificial radar telescope satellite in geosyncronous orbit around Mars to help locate dangerous asteroids on a trajectory that would place them on a path to strike Earth?
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Geosynchronous orbits around other Solar System objects

Earth's geostationary orbit has many human-made satellites which have helped vastly with communications and research. Aside from this artificial collection, are there any other objects orbiting a ...
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1answer
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Are there cubesats in GEO?

This answer to the question How often do reaction wheels require desaturation, normally? says: One practical example I know of is for a 6U in GEO that is always sun pointed, there's a thruster ...
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At which point would two GSO/GEO satellites with similar orbital elements be closest to each other?

While I was answering another question on How closely spaced are satellites at GEO I came to realize I can't really word it with much conviction how two close proximity satellites in GEO/GSO orbits ...
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1answer
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How are co-located satellites positioned relative to each other?

I'm trying to learn about co-located GEO satellites. When I first heard about them, coming from a planetary orbital mechanics background, the first thing I pictured was based on the epicyclic ...
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How does gravitational stability change with the distance from special places such as geostationary orbit and lagrange points?

How rapid do the attractive properties of GEO and lagrange points deteriorate with the distance from optimum? How "large" are such locations? At what distance would station keeping require, say, twice ...
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Could a communication satellite that fails to reach GEO be repurposed?

When a launcher's upper stage fails to put a commercial communication satellite in geostationary orbit, it cannot be used as intended. But could it be used in satellite-to-satellite communication ...
7
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Needed height from the release of a space elevator to get a stable elliptical orbit?

As we know, something released from around 36000 km height from a space elevator will remain in geostationary orbit around the Earth. Things released from lower will go into an elliptical orbit ...
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Differences between launch injection and transfer orbits for geostationary satellites

I am familiar with all different orbits but I struggle with the new launch injection method in GTO. What are the differences between sub-synchronous and super-synchronous transfer orbits compared to ...
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What is the process for allocating GEO slots to commercial satellites?

Building off of this previous question, is there a more detailed summary anywhere of the process that a commercial satellite would have to go through to obtain a GEO slot? The documentation I have ...
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How do communication satellites remain positioned above a particular region?

From what I understand, an object has to keep moving in an orbit to not come crashing down to Earth. (The ISS is the first thing I think of for this.) How then, do satellites which are purpose built ...
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Delta-v to move from GEO to GEO

To move a satellite in geostationary orbit, 166°55′E, to the antipode, 13° 4' 3.2" W, what delta-V would be needed for this to be accomplished? As for time constraints, I do not know what are the ...
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Is there a synchronous orbital height for Phobos?

My assumption is that any body in the solar system would have it's own specific geo-synchronous orbit height. But when I took a look at Phobos and calculated the GEO height based on the simple formula ...
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What is a typical satellite solar panel mass?

Does anyone know a reliable source to find the mass of solar panels on satellites (in particular GEO satellites)? I know they will vary but I am struggling to even find one data point let alone a ...
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How stationary is geostationary?

When a satellite is in geostationary orbit, it is supposed to stay above one spot of the earth and rotate around the earth at the same rate the earth spins. But how exact does that equality need to be?...
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What is typical lifetime of GTO rocket stages before reentry?

Most of geostationary satellites are launched at geostationary transfer orbit (GTO) first by rocket's upper stage. Than satellites separate and circularize the orbit by own propulsion. The upper ...
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Given the orbital radius of a satellite, how is the orbital period calculated?

I know I can find the orbit radius of a satellite from the equation: $$r=\sqrt[3]{\frac{T^2GM}{4 \pi^2}}$$ but what determines the orbit period $T$? If I assume a geosynchronous orbit, would that ...
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Orbital altitudes, are some better than others and why?

The geostationary orbit of about 35,786 km above mean sea-level allows satellites to rotate at the same speed as the Earth on its axis, making them seem as if they don't move relative to the ground. ...
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Why is the SES launch going to an apogee of 80,000 km?

Why is the apogee of the Falcon 9 SES launch going clear out to 80,000 km? GEO is only 36,000 km or so, it seems like a waste to go so far beyond it.
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Why will GOES-R take a whole year for validation?

I've been reading a few things about NOAA's GOES-R satellite, and I noticed this on the GOES-R site: ...will be placed in the 89.5° checkout orbit where it will undergo an extended checkout and ...
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Determining GEO Orbital Slot from TLE

I'm trying to figure out the equation based on TLE data which orbital slot a GEO satellites occupies. I have the TLE data imported into R and I wish to know what satellites are in adjoining GEO ...
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What's the closest that an Apollo mission passed GEO on its way to the moon?

@Uwe's comment No astronaut ever visited geostationary orbit at 22-23k miles to maintain or deploy satellites. The Apollo astronauts just rushed by on their way to the Moon and back. below the ...
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At what magnitude would adjacent large geostationary communications satellites see each other?

Imagine I'm sitting on a geostationary satellite. I can see the Earth in front of me. It's about the size of a soccer ball at arm's length. To the left and right, I can see similar satellites in the ...
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For which applications are LEO and GEO substitutable?

This article, this article, and this earlier question indicate that, given enough satellites in LEO, it's possible to substitute between GEO and LEO. The first article and the question have some ...
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Most fuel-efficient deorbit from geostationary

Say a spacecraft in geostationary orbit needs to be deorbited (not very common, but bear with me). How does one decide when and how long should the retrograde burns be, in order to have started with ...