Japan loses contact with new space 'scope just weeks after launch Japan's newest space telescope has mysteriously gone quiet barely a month after launch, and engineers at the Japan Aerospace Exploration Agency (JAXA) are desperately trying to reestablish contact. On February 17, the x-ray telescope ASTRO-H blasted off from Tanegashima Space Center and successfully made it into orbit, at …
How high is it? Is it in one of the main debris zones?
According to the font of all knowledge, Hitomi née Astro-H is in a 560 x 581km orbit at 31 degrees inclination. That's in LEO, which is pretty dirty and has satellites in numerous orbital planes that endanger a satellite with debris from all angles and even head-on velocities of over 14km/s.
Further, an orbit with a 570km semi-major axis is above the vague safe zone (< 400km) where the atmosphere has a debris-sweeping effect. Debris at 570km will be fast, from all directions, and longer-lived than at the ISS's altitude.
On the other hand, the Hubble has successfully operated at 540km for decades.
The change in observed orbit implies a fairly significant impulse (momentum), the fact that the debris is in almost the same orbit implies high mass & relatively low velocity. High velocity would cease a large debris plume as what happened when an Iridium satellite collided with a cosmos satellite. My bet is a propellant tank let go.
I'm thinking that it is more like the beginning of "Wall-E", where Earth orbit is packed with wall-to-wall satellites.
The "Gravity" scenario is that debris from the Russian stage that exploded while sending ExoMars into trans-Mars insertion have now taken out Astro-H.
Well, I hope the telescope can be stabilized and return to use!!
Are there really people who say that you can't put an observatory satellite into orbit? 20 years or so after Hubble went up, and all the other orbital observatory successes since then? I might be a naysayer if we were talking $10 billion or $20 billion to put a single satellite up there, but the technology and practices are already well-proven.
The larger issue is the amount of orbital debris up there. If we are going to start having ongoing difficulty with debris strikes, then that really will screw up our ability to productively use Earth orbit.
It looks like, electronically, the probe has lost its capability. It is far-enough up there that it won't be coming down in the ensuing months, so only the Japanese are in a rush to find out what it is going to do.
It WAS working, so this had to be some kind of external-hit or reorientation misfire. That there appears to be 'other pieces' near it argues more for a fuel-tank malfunction, but LOTS of other things could have happened. You may recall the movie portrayal of such a problem on Apollo 13. It can be very messy.
Good luck to the Japanese on figuring this out and correcting it!
At least that's the sense I get from the guy quoted in the article. I get that it is supposed to be gyro stabilized, but if it started rotating (for whatever reason) at some point it will overwhelm the ability of gyros to compensate. I assume it has some thrusters that could correct for the rotation if they can determine how it is rotating? And while the main antenna that communicates with the Earth would be directional, don't satellites always include a low data rate omnidirectional antenna or two for cases like this?
Obviously if something exploded or it took a hit it may be irreparably damaged, but if it is intact and spinning, I would think they could get it working again once they determine exactly how it is spinning.
Everyone loves a good problem even though, when sufficiently well-specified, the problem dictates its solution. Of course, the devil is in the details--direction and means of communication, assessing the sat for what's still working, calculating delays in communications and timing of any instructions, quantity of thrust to be applied, etc. Before you know it, you're doing rocket science.
Fireball XL5 has been grounded for 50+ years Steve just couldn't take it any more, the risk of hitting all that flying sputnik junk just tipped him over the edge, Steves in Rehab after a binge session with Venus and Doc, Zooney was no help during flight and Robert kept bursting into flame.
I am not inferring that Japanese space engineers built Robert.
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