Posted on 04/13/2005 6:57:43 PM PDT by iso
Orbital Sciences has successfully launched the XSS-11 satellite aboard a Minotaur I rocket. The XSS-11 is an experimental small satellite for the US Air Force designed to test technologies that could allow quick visual examinations or maintenance of spacecraft in orbit.
The mission originated on Monday, April 11, 2005, at 9:35 a.m. (EDT) from Vandenberg Air Force Base, CA (VAFB) when the Minotaur rocket ignited its first stage motor and lifted-off from its West Coast launch site.
Approximately 12 minutes after launch, the XSS-11 satellite was inserted into its targeted orbit of approximately 850 kilometers above the Earth. Yesterday's mission was the third flight the Minotaur I space launch vehicle, all of which have been successful.
Since the program's first flight in 2000, the Minotaur family of space and suborbital launch vehicles has carried out eight launches with 100% success.
Over the next three years, Minotaur rockets are scheduled to conduct another nine launches, including the first flights of the larger Peacekeeper-based vehicles.
The Minotaur I space launch vehicle used in yesterday's successful launch of the XSS-11 satellite is the first in Orbital's Minotaur product line, which includes both space launch vehicles as well as long-range missile defense targets and other suborbital vehicles.
The rockets are derived from U.S. Government-supplied Minuteman and Peacekeeper rocket motors.
The space launch configurations combine commercial rocket motors, avionics and other elements with the government-supplied stages to create responsive, reliable and low-cost launch systems for U.S. government payloads.
The Minotaur I configuration includes Minuteman rocket motors that serve as the vehicle's first and second stages, efficiently reusing motors that have been previously decommissioned.
Its third and fourth stages, structures and payload fairing are common with Orbital's highly reliable Pegasus XL rocket.
The Minotaur I space launch vehicle made its inaugural flight in January 2000, successfully delivering a number of small military and university satellites into orbit and marking the first-ever use of residual U.S. Government Minuteman boosters in a space launch vehicle.
Its second mission was carried out less than six months later, in July 2000, with the launch of a technology demonstration satellite for the U.S. Air Force Research Laboratory.
Ping !
Can you say "satellite killer". I'm sure the Chinese, French and Russians can.
Thank you DARPA. Good work again. You keep our enemies nervous.
I wonder why that doesn't make YOU nervous? It sure makes me nervous. You must really trust that this will only be controlled by our friends. I can imagine some pretty nightmarish scenarios around this.
Not really nervous. I'd say space belongs to us right now. Only the Russians can even come close to us. I'd say we have a 15 year jump on everyone else in most areas related to space. (don't judge what the miltary does by the shuttle!)
And we must continue dominance of space. We need not only defensive and recon, but also OFFENSIVE satellites/space weapons. I am talking lasers and/or space based railguns. Space is the ultimate high ground and we must have the option of Death from Above.
Good idea :) One alternative to space based railguns is to simply release a projectile then use thrusters to deorbit the projectile.
A kinetic 'satellite-killer,' particularly in Low Earth Orbit, would be seriously counter-productive to a country that relies on satellites as much as the US. The shrapnel from such a destruction would present a serious, and uncontrolled, navigation hazard to other (read: our) spacecraft. Also, the list of other countries that could throw up a kinetic energy type system to hit our satellites is fairly long (anyone with an ICBM, plus a few others that you might not expect), so to suggest that we could operate such a weapon with impunity is perhaps overstating the fact somewhat.
-SV
A dockable bus system would indeed be cool - there are several projects out there working on such a beast, although they're purpose-built to be dockable - most other spacecraft are less friendly to a would-be approacher.
And while satellites are pretty fragile in comparison to much of what we deal with on an everyday basis, they're also generally designed with fault protection and redundancy sufficient to allow them to continue with their mission should a portion of the spacecraft become non-operational.
My personal opinion is that we should let spacecraft on-orbit be, in general. Uncontrolled debris is (are?) less than fun, and even getting close enough to do 'minor' damage to spacecraft entails the risk that you'll get close enough to crash. Plus, there's something to be said for know where someone's space assets are at all times (in many respects, that's better than trying to defeat them)...
-SV
Don't laugh, but the approach I was thinking of was similar the use of a lasso or a grappling hook. Have a small rocket like a sidewinder attached to the line and fire it straight down. End of satellite :)
Just occurred to me that if you had a small 2 stage rocket you could simply push the satellite out of orbit, sort of the way a pusher tug moves an oil barge. First stage puts the rocket in position and makes contact (maybe a grabbing mechanism), the second one is aimed to reduce it's speed so it falls out of orbit. This way it's gone in one piece.
Interesting idea.
Off the top of my head, I'd have a couple of concerns. The first is that even small spacecraft would probably need something more powerful than a AIM-9 to de-orbit them. If you could tether yourself to a spacecraft, I'd guess that it would be more efficient (mass-wise) to just use the motor on the spacecraft you've launched (which would need to be a decent size to get to a reasonable number of spacecraft upon launch). The tether itself is probably the biggest obstacle - guiding it on-orbit would be tough, to say the least, and since most spacecraft aren't designed to be lassoed (or grappled), it'd be awfully touchy to make sure you don't just rip the target to pieces as you try and tug it out of orbit. Plus, a tether introduces some weird, space-specific problems like differential charging, and the orbital mechanics could get pretty hairy (which lead to the aforementioned problems with crashing)...
I think, as fun as it sounds to lasso a spacecraft, I'd probably still just leave the silly buggers up there...
-SV
The problems with orbital rendezvous are still there in this case (suprisingly non-trivial), and remember that most spacecraft don't really have a nice, flat surface to push against (or if they do, it may not be facing the direction you need), so predicting the behaviour of the docked system would be an interesting excercise in chaos theory. Plus, a docked system may have funny dynamics during re-entry. Another thing that occurs to me is that we have to recall that the other spacecraft is probably going to react to something pushing/docking or otherwise interacting with it (the attitude control system, at the least, is going to fight the motion imparted (or try to execute pre-planned maneuvers) and the ground may well intervene at some point.
There's another aspect of this that could also play into an interceptor spacecraft. Spacecraft aren't cheap, and neither are launch vehicles. And both have pretty severe operating restrictions in terms of timing, availability and such.
The US developed (and tested) a satellite interceptor. It was, as I recall, launched from an F-15, and targeted a satellite that was mostly (but not completely) finished with it's mission. It did hit, but the interceptor program was, to my knowledge, not pursued much after that. The fighter launched system is nice because it's more portable, and less subject to some of the confining elements of a ground-launched system, but the tradeoff is that you get a small rocket and interceptor vehicle. In the end, I suspect that the increasing US reliance on space assets made satellite interception more risky than it was worth in terms of risk to our own vehicles, both from successful and un-sucessful attempts.
The Russians also developed some systems that could be used to defeat LEO spacecraft in a pinch (originally designed to intercept ICBM re-entry vehicles), although without much precision (nuclear warhead)...
-SV
It's the getting the tether in a position where it's motion would actually cause it to wrap around the target that'd be the big deal, from my perspective. Plus, deciding what the length of the tether is would be an interesting trade - to short, and you're just begging for a collision. To long, and you can't control it very accurately.
A penatrating projectile would be more likely. Force distribution would be a problem, I would think, as the interior of the target is likely covered in electronics and other equipment, and isn't likely to present a nice flat surface to spread the load. You'd get a bunch of points of concentrated force, and shortly thereafter, a nice cloud of satellite bits...
In terms of spacecraft orientation, most low-earth spacecraft are actually fairly agile - they generally re-orient frequently to target their payload at specific points on the earth. The more earth-fixed spacecraft generally operate out further out (impractically far for intercept attempts - Geostationary orbit is something on the order of 22,000 miles out). Low-Earth orbit stuff is usually in the 200-700 mile apogee range, I think. It'd take a fair bit of delta-v to get down to where atmospheric drag had an effect.
If I were given the task of removing a spacecraft from operation, I'd probably find a way to get access to the control centre of the target, and try and command it into a de-orbit (or in the case of a GEO, into the retirement orbit) rather than attempt to perform some kind of orbital intercept.
-SV
My knowledge of the strategic arms agreements is pretty hazy, but I thought I remembered the ABM agreements to concern mostly static systems. The agreement, if I'm remembering right, allowed both the US and USSR to deploy a single system around a fixed geographic area - the Russians chose Moscow, and not too many years ago, it was still in 'operation,' although the operability of the interceptor vehicles was a major open question. The US retired it's system in the late 70's.
The ASAT system was tested in the very late 70's (in technical violation of the 'no development' agreements in some of the treaties), but was not pursued much past the development phase (although it was successfully tested against an operational satellite).
I would expect the big problem with wrecking a satellite is that you've got an uncontrolled thing up there when you're done. It's better than simply smashing it, 'cause a large single object is easier to track and plan around, but since it's uncontrollable, it'll be a lurking threat.
This kind of speculation is fun, although I'm stuck approaching it from the engineers point of view (which is basically throwing rocks at any and all ideas... heh).
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