Chance of 99942 Apophis Messing up GSO Satellites?

[Redrobin]

So I saw that 99942 Apophis will pass within the orbit of GSO satellites in 2029. Will this have an effect on the orbits of GSO satellites?

[Scotius]

There is always a chance - but it's astronomically tiny Apophis is rather small, with negligible gravity. Our GEO-sats are even smaller - plenty of space for everything around geostationary orbit.

[Guest]

It shouldn't, unless it hits one of them. Which would be one heck of a bad luck, since the likelihood of impact is minimal.

[mdatspace]

Small rock with minimal gravitational pull. Nothing will change.

[andrewas]

It weighs about forty billion tons. At a distance of 100 kilometers, it would accelerate a small object at ~2.7*10^-10g. So it might produce measurable effects if it passes close to a satellite and anyone cares to measure that satellite very closely, but it isn't massive enough to cause significant disruptions unless it hits something. A very near miss, within 50 meters of the surface, still only causes ~2.2^10^-5g acceleration, and that would only last for a fraction of a second so the total velocity change would be miniscule.

[Nibb31]

GSO sats are on an equatorial inclination, which is 23.4° from the ecliptic plane. I doubt that a random asteroid will be anywhere near that inclination.

[Tommygun]

GSO sats are on an equatorial inclination, which is 23.4° from the ecliptic plane. I doubt that a random asteroid will be anywhere near that inclination.

I'm curious, why are the sats on that inclination, is it for safety?

[SargeRho]

Because Geostationary Orbit only works above the equator of the planet, else it will bob "up" and "down" over the course of each orbit, and lose coverage of parts of he globe during different phases of the orbit.

[Nibb31]

I'm curious, why are the sats on that inclination, is it for safety?

Because a geosynchronous orbit can only be on the equatorial plane at 36000 km. If you put a satellite anywhere else, it won't be geosynchronous.

[J.Random]

Because a geosynchronous orbit can only be on the equatorial plane at 36000 km. If you put a satellite anywhere else, it won't be geosynchronous.

I think you're confusing geosynchronous with geostationary.

[Tommygun]

Oh I see, I forgot about Earth's axial tilt is 23.4 degrees.

[Dkmdlb]

Geostationary satellites must be on the equatorial plane. Geosynchronous satellites must have a period equal to one sidereal day, no matter the inclination.

Note that you can have a geosynchronous satellite in orbit on the equatorial plane that is not geostationary.

[Red Iron Crown]

Geostationary satellites must be on the equatorial plane. Geosynchronous satellites must have a period equal to one sidereal day, no matter the inclination.

Note that you can have a geosynchronous satellite in orbit on the equatorial plane that is not geostationary.

Through eccentricity? I think that would make it oscillate east and west when viewed from Earth, correct? (There's a better word than oscillate but I can't recall it at the moment.)

[Tommygun]

Through eccentricity? I think that would make it oscillate east and west when viewed from Earth, correct? (There's a better word than oscillate but I can't recall it at the moment.)

sinusoidal?

Harmonic Motion?

[deadshot462]

Even if there were, I believe most GSO satellites have engines that can adjust their orbit for any errors in the long term.

[Armchair Rocket Scientist]

sinusoidal?

Harmonic Motion?

Librate.

10ch10ch10ch

[FREEFALL1984]

even in the in unlikely event that a satellite is pulled from its orbit or otherwise damaged, you wouldn't notice the difference. The system is far over engineered. losing even a couple of satellites could still provide you with navigable coordinates, depending on which satellites failed.

[R0cketC0der]

Haven't done the math on it, but I would assume that even if it got in a kilometer of a satellite, the moon would still have a larger gravitational pull on it. The gravity of asteroids is just tiny.

[Nibb31]

even in the in unlikely event that a satellite is pulled from its orbit or otherwise damaged, you wouldn't notice the difference. The system is far over engineered. losing even a couple of satellites could still provide you with navigable coordinates, depending on which satellites failed.

You're talking about GPS satellites. Those are way below geostationary orbit and way out of the way of Apophis.

[FREEFALL1984]

Its also worth noting that the GNSS' currently in operation do not operate in a geostationary orbit but in a network encompassing various altitudes and inclinations. The satellite itself regularly transmits orbital data and a accurate time stamp at regular intervals using a high frequency line of sight radio system, this data is then deciphered by the user end hardware and an exact current location and local time is established. at any given moment there are up to 8 satellites just from the NAVSTAR network alone within direct line of sight, removing one of these satellites has little to no effect on the final location, since you only really need 3 satellites to triangulate a Geospatial location. Currently the Indian IRNSS system is the only system based entirely on geostationary satellites and since there are only 2 satellites launched so far the system is not operational.

haha ninjd

[FREEFALL1984]

You're talking about GPS satellites. Those are way below geostationary orbit and way out of the way of Apophis.

Russian GNSS has several satellites in GSO

[Nibb31]

My understanding is that GLONASS sats are at 19000km. GPS sats are at 20000km. GSO is 36000km.

[FREEFALL1984]

My understanding is that GLONASS sats are at 19000km. GPS sats are at 20000km. GSO is 36000km.

sorry I got mixed up with the Chinese Compass system. which has 6 in GSO, and the rest at 21km,

I also assumed the GPS system would be the only system really effected at any length by a passing body since its the only system with location critical satellites, most communication systems tend to have a little more tolerance in their exactitude providing they maintain line of sight,

[Kryten]

The effect of the asteroid on GSO sats will be far lower than that of the moon or irregularities in the earth, both of which they already deal with fine. Satellites aren't just placed in GSO and left there, they have to be able to maintain position or they rapidly start drifting.

[Dkmdlb]

Through eccentricity? I think that would make it oscillate east and west when viewed from Earth, correct? (There's a better word than oscillate but I can't recall it at the moment.)

Yes, but geosynchronous means just that the satellite will be in the same place over earth at the same time each day. So if it oscillates east and west, that's fine, as long as it has an orbital period exactly equal to earth's day. You can even have a highly inclined or even polar geosynchronous orbit.