What is the X-37 for?

[crazyewok]

I heard one mission was for growing crystals for some of the military optic and weapon systems in development.

That and testing equipment for extreme conditions.

Of course I cant give any citation as it was something passed on by a friend. So take it as you will.

[deadshot462]

Well it's sized for Kerbals so I'll conclude that the US Government found the existence of Kerbals and is keeping them in orbit until they figure out what to do.

[Kryten]

I remember reading in a Pentagon paper years ago that the USA wanted to develop a weapons delivery platform that could deliver a guided 500lb warhead anywhere on earth within 20 minutes of the order being given. This would have that capability if it was kept in orbit during times of tension.

Plane changes to hit anywhere not directly under the orbit path would take a lot longer than twenty minutes. That program turned into FALCON/HTV, pretty much just an ICBM with a maneuverable warhead; incidentally the program under which SpaceX got the seed funding for Falcon 1.

Edited April 27, 2015 by Kryten

[m4rt14n]

X-COM project..

[Leszek]

Now that 1.0 has come out I can confirm that the X-37's purpose is to test the new stock aero. Pretty obvious in hindsight, I don't know how any of you didn't figure it out.

[Frida Space]

From SpaceflightNow:

Meanwhile, Air Force officials have provided more detail on the propulsion experiment to be conducted on this X-37B mission. It is a Hall thruster electric propulsion test to enable in-space characterization of design modifications that are intended to improve performance to the units onboard Advanced Extremely High Frequency military communications spacecraft, officials said Monday.

Produced by Aerojet Rocktdyne, the AEHF satellites’ Hall thrusters are 4.5-kilowatt units that use electricity and xenon to produce thrust for maneuvering satellites in space. The novel electric propulsion system produces a whisper-like thrust by ionizing and accelerating xenon gas.

Unlike conventional chemical engines that deliver substantial boosts with each brief firing, the electric system needs the stamina to operate for exceptionally long periods of time to harness its 0.06-pound-thrust [0.27 newtons] into orbit-changing power.

The divergent systems have their advantages and drawbacks. Although typical engines can maneuver satellites rapidly, they use large amounts of heavy fuel that in turn require a bigger, more expensive rocket to carry the spacecraft. Electric propulsion gives up timeliness for efficiency since its xenon fuel weighs a mere fraction of conventional hydrazine, but you must have patience to reap the rewards.

Each of the AEHF satellites, valued at over $1 billion, is a nuclear-survivable spacecraft that would ensure American leadership with communications in the most hellish scenarios of war imaginable. Three such satellites have been deployed to date, with three more planned.

The on-orbit test plans for the X-37B experiment are being developed by Air Force Research Laboratory and administered by the Rapid Capabilities Office, which runs the X-37B program.

“The experiment will include collection of telemetry from the Hall thruster operating in the space environment as well as measurement of the thrust imparted on the vehicle. The resulting data will be used to validate and improve Hall thruster and environmental modeling capabilities, which enhance the ability to extrapolate ground test results to actual on-orbit performance,†the Air Force said.

[musicpenguin]

To rescue Jeb of course!

[Alias72]

The Hall Effect test is nice and all, but that is not why they built this vehicle. The soviet union first used hall effect thrusters in 1971 and after the fall of the USSR the design entered Europe and American Space agencies where it is now available to power your satellites and put on pretty light shows at University engineering parties.

The vehicle is most likely a floating lab for micro gravity materials testing. The air force may be looking at blowing up satellites and nuclear warheads while in transit. They may also want to develop new crystals. Perhaps for laser lenses.

[ComradeWolfe]

It seems to me that the main advantage is cost and configurability. Say a target nation brings a new comms or weapons system online -- will an existing satellite be capable of listening on the right frequencies? Possibly, but odds are a specialized target-specific payload would be more effective high enough priority missions. Being specialized (tailored to target) the payload would be a lot smaller than a general purpose radio or optical system, hence the use of a smaller craft.

Also, it lets you pick a different orbit as needed. This is important for intercepting ground-based point microwave links. Towers that communicate using narrow beams with line of sight are often impossible to intercept from the ground or above, in which case the only viable option is a sat in an orbit that places it low on the horizon "behind" the receiving tower.

You can also place it by a target satellite in order to intercept comms with a ground station or between two target sats. Again the benefit is that you're 'in' the narrow beam of transmission.

Finally, yes there is likely a scientific benefit in the fields of hypersonic flight and lifting bodies, but I doubt they actually carry much by way of NASA payloads. Remember, Discoverer's "scientific" payload turned out to be cameras pointed at the Soviets.

[SciMan]

I would imagine that the X-37's is mostly a re-usable US Air Force owned and operated version of NASA's LDEF satellite.

Of course, it wouldn't surprise me at all if they also had at least plans for some kind of spy satellite or anti-satellite capability. And they're probably working on abilities to recover or closely inspect foreign satellites too. It could probably get sub-millimeter resolution from within a few kilometers, with the right lenses.

Ground strike capability can be ruled right out, it doesn't have the payload for a meaningful effect on target, and why would you need it reusable in that case anyways? Additionally, the first time that system is used, it gives Russia, China, and every other nation that might have anti-satellite weapons a very good reason to use them.

[Frida Space]

Known as the Materials Exposure and Technology Innovation in Space, or METIS, the investigation on the X-37B will expose nearly 100 different materials samples to the space environment for more than 200 days, NASA says. METIS is building upon data obtained by several missions of the Materials on International Space Station Experiment (MISSE), which flew more than 4,000 samples in space from 2001 to 2013.

Source: http://spaceflightnow.com/2015/05/06/nasa-gives-more-information-on-its-experiment-aboard-the-x-37b/

[totalitor]

Payload bay is 2.1 m × 1.2 m. Just to put a an astronaut inside. Would it be possible an astronaut in spacesuit would be launched to orbit, he makes a space walk, taking some pictures, and then he would return to earth. One orbit round is about 90 minutes, small enough to do everything this.

Would an astronaut survive from g-forces and re-entry heating?

[xenomorph555]

Payload bay is 2.1 m × 1.2 m. Just to put a an astronaut inside. Would it be possible an astronaut in spacesuit would be launched to orbit, he makes a space walk, taking some pictures, and then he would return to earth. One orbit round is about 90 minutes, small enough to do everything this.

Would an astronaut survive from g-forces and re-entry heating?

G-force and heat is okay, however it is a bit cramped but possible.

It would require a really slim EVA suit with a good few hours of life support. I recommend the soviet Yastreb suit;

Small, light, slim and comes with 2.5 hours of life support.

Not that this mission would be worth it in anyway though.

[Wesreidau]

Ever watch Ice Station Zebra?

I recall the Shuttle had a requirement to be able to land with its payload still aboard. I think the X-37 is for that purpose; if the Air Force wants to launch something with cutting-edge crypto or somesuch, there's an obvious fear that what went up will come down outside US airspace and possibly in the enormous land-mass of China, Russia, and their spheres of influence. So the X-37 exists as a guided parachute; return a sensitive payload to American airfield, or slam into a mountainside at Mach 6. That's why it isn't obviously useful, we're all thinking about going up, but it was designed for going down.

[Teutooni]

Ever watch Ice Station Zebra?

I recall the Shuttle had a requirement to be able to land with its payload still aboard. I think the X-37 is for that purpose; if the Air Force wants to launch something with cutting-edge crypto or somesuch, there's an obvious fear that what went up will come down outside US airspace and possibly in the enormous land-mass of China, Russia, and their spheres of influence. So the X-37 exists as a guided parachute; return a sensitive payload to American airfield, or slam into a mountainside at Mach 6. That's why it isn't obviously useful, we're all thinking about going up, but it was designed for going down.

Much easier to design a unit that self-destructs upon re-entry. De-orbit and blow up a small explosive aboard, scattering anything useful to a million pieces that burn fast. They want something back, and that something is test items/data for analysis.

[Wesreidau]

Much easier to design a unit that self-destructs upon re-entry. De-orbit and blow up a small explosive aboard, scattering anything useful to a million pieces that burn fast. They want something back, and that something is test items/data for analysis.

And there goes a half-billion dollar spy satellite? Hardly. They want to bring something back, you're right. They want to bring back their own cargos.

[Kryten]

And there goes a half-billion dollar spy satellite?

They've been fine doing it with every single previous US spy satellite, and had no real issues with it. A payload small enough to fit in the X-37 cargo bay is not going to be one that's not worth going through all this bother with.

Edited May 22, 2015 by Kryten

[magnemoe]

They've been fine doing it with every single previous US spy satellite, and had no real issues with it. A payload small enough to fit in the X-37 cargo bay is going to be one that's not worth going through all this bother with.

This, refueling the satellite would make more sense, however no need to use the X-37 for this but an small and cheap satellite with extra fuel.

[Wesreidau]

The Shuttle bay was engineered around fitting a Hexagon inside. The Shuttle wings were designed to return a full cargo bay after 1000 nm of glide. The Shuttle had to launch into a polar orbit and conduct a one-orbit-return with payload in case of emergency. Air Force requirements drove the Shuttle design. Hexagon had an elaborate power generation, station-keeping, and film-deorbiting requirement on top of the cameras themselves. The X-37 won't fit a Hexagon, no. But it can fit cameras. I think after the Air Force got burned expecting the Shuttle for in-orbit Hexagon refurbishment failing to materialize they decided to make their own system for satellite retrieval. They may also have developed a camera module for the cargo bay itself. But I can't possibly see them snatching other nation's satellites out of the sky. Unless something is designed to be clamped down in the cargo bay its going to be a bowling ball in a cardboard box all the way back to Earth.