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US Space Force reveals first look at secretive X-37B space plane in orbit

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Re: US Space Force reveals first look at secretive X-37B space plane in orbit

#81

Earlier quoted context omitted.

I was going to say, not out of range of anti-satellite missiles, at least at a low perigee... But maybe it's zipping too fast there to be easily shot down? Whereas at apogee, when it's slow, it's also very far away.

> But maybe it's zipping too fast there to be easily shot down? A satellite in LEO already has a speed of about 8 km/s. The highest speed of a satellite in a highly elliptical orbit is 11 km/s. It you can shoot a satellite at 8 km/s, you probably can also shoot it at 11 km/s. The problem is, of course, that the perigee of a satellite in a highly elliptical orbit can be over a different part of the planet than your SA…

> It you can shoot a satellite at 8 km/s, you probably can also shoot it at 11 km/s.

Assuming all else is equal (same altitude, same targeting capability, same flight characteristics), an interceptor for an 11 km/s target needs about 89% more kinetic energy than an interceptor for an 8 km/s target. Realistically, between the rocket equation and atmospheric effects, the faster interceptor would likely need to be far larger still. You're probably talking about a 2.5 to 3 times bigger missile. While a country that could develop one could likely develop the other if they so chose, it doesn't seem like a safe assumption that a country with one has the other.

Re: US Space Force reveals first look at secretive X-37B space plane in orbit

#82
post #7
post #5

I can't be the only one who, when I read "space force" hears a deep, reverb-heavy, Buck Rogers kind of voice going "spaaaaaaaace foooooooorce"

a pretty good satire of the whole thing: https://en.wikipedia.org/wiki/Space_Force_(TV_series)

There were legitimate reasons for spitting USSF as its own service. The only reason people made fun of it was because Trump signed the order for it.

Re: US Space Force reveals first look at secretive X-37B space plane in orbit

#83
post #53

Earlier quoted context omitted.

Already have, SpaceX have been doing a few NRO launches. Delta and Titan are retired, and Atlas is down to its last few.

Great, but I specifically said Keyhole from which Hubble was a descendant. Which Keyhole bird was launched by SpaceX?

None, but that's why they said soon. I'm sure a modified FH or Starship could get deploy this hardware. The last launch of in 2022 on a Delta IV Heavy.

Re: US Space Force reveals first look at secretive X-37B space plane in orbit

#84
post #81

Earlier quoted context omitted.

> But maybe it's zipping too fast there to be easily shot down? A satellite in LEO already has a speed of about 8 km/s. The highest speed of a satellite in a highly elliptical orbit is 11 km/s. It you can shoot a satellite at 8 km/s, you probably can also shoot it at 11 km/s. The problem is, of course, that the perigee of a satellite in a highly elliptical orbit can be over a different part of the planet than your SA…

> It you can shoot a satellite at 8 km/s, you probably can also shoot it at 11 km/s. Assuming all else is equal (same altitude, same targeting capability, same flight characteristics), an interceptor for an 11 km/s target needs about 89% more kinetic energy than an interceptor for an 8 km/s target. Realistically, between the rocket equation and atmospheric effects, the faster interceptor would likely need to be far l…

I dont think that it is correct to assume your interceptor needs to match velocity. Any speed will do if you can intercept it on approach instead of chase it down.

Re: US Space Force reveals first look at secretive X-37B space plane in orbit

#85

Earlier quoted context omitted.

Great, but I specifically said Keyhole from which Hubble was a descendant. Which Keyhole bird was launched by SpaceX?

None, but that's why they said soon. I'm sure a modified FH or Starship could get deploy this hardware. The last launch of in 2022 on a Delta IV Heavy.

No, I said soon. The person I replied to said "already have".

Re: US Space Force reveals first look at secretive X-37B space plane in orbit

#86

Earlier quoted context omitted.

None, but that's why they said soon. I'm sure a modified FH or Starship could get deploy this hardware. The last launch of in 2022 on a Delta IV Heavy.

No, I said soon. The person I replied to said "already have".

[deleted]

Re: US Space Force reveals first look at secretive X-37B space plane in orbit

#87
post #8

Why might it be desirable to have an observation craft so far away from the earth? I'm having a hard time imagining the advantage compared to being a bit closer, unless it's a more energy-efficient parking situation while the vehicle isn't in active use.

My understanding is it’s on an offset elliptical orbit. This is essentially the farthest point away from earth with the other end of orbit being very close to Earth. From a tactical perspective, that means this can interact with basically any other satellite.

Past flights have been years long and are classified what might have even been achieved. I wonder how much of the space war doesn’t ever get published?

Re: US Space Force reveals first look at secretive X-37B space plane in orbit

#88

Earlier quoted context omitted.

My orbital mechanics is (like most people) weak, is this intended as a generalized physical threat to other satellites?

Intended? I don't know, you'd have to ask NASA. Does it have that capability? Sure, if it can deploy arbitrary payloads on destination.

It has carried payloads before but little is known about its missions.

Re: US Space Force reveals first look at secretive X-37B space plane in orbit

#89
post #8

Why might it be desirable to have an observation craft so far away from the earth? I'm having a hard time imagining the advantage compared to being a bit closer, unless it's a more energy-efficient parking situation while the vehicle isn't in active use.

How can you tell that is the earth?

Re: US Space Force reveals first look at secretive X-37B space plane in orbit

#90
post #7
post #5

I can't be the only one who, when I read "space force" hears a deep, reverb-heavy, Buck Rogers kind of voice going "spaaaaaaaace foooooooorce"

a pretty good satire of the whole thing: https://en.wikipedia.org/wiki/Space_Force_(TV_series)

The show has basically 0 relation to what the Space Force actually does
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