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In the news item on the website of ABC's affiliate station WFTV in Florida Official: SpaceX explosion nearly destroyed asteroid-seeking OSIRIS-REx spacecraft, there is discussion of a loss of pressure and cooling following the SpaceX 'fast fire' (explosion) during a test on September 1st, 2016. I don't understand what kind of pressure or cooling was lost, and how that could have destroyed OSIRIS-REx.

I am not even sure how far apart these two rockets were, or why their systems were coupled in such a way that a failure at one location could so easily lead to the failure of critical systems and potential loss of an expensive payload at a different location. It's not like rockets never explode.

Could someone either show a map, or give GPS coordinates that can be googled that illustrate exactly where these two rockets were at the time? What are the "adjoining facilities" mentioned below? It almost sounds like the technicians had to run in to a burning building to fix a refrigerator!

OSIRIS-REx was sitting atop an Atlas V rocket at an adjoining facility, set to launch a week later, when the SpaceX rocket exploded during a static test, NASA said.

In a release, 45th Space Wing mission support group commander Lt. Col. Greg Lindsey, detailed the emergency response to the explosion at Cape Canaveral Air Force Station.

Included in his description was information on how technicians had to fight to save OSIRIS-REx as emergency personnel put out fires from the SpaceX explosion.

As his teams responded to the explosion, Lindsey was told that the cooling system at Launch Complex 41 was losing pressure.

“Without those chillers, the spacecraft for the next launch (OSIRIS-REx) would be lost,” he said. “Needless to say, at this point I had to reestablish our priorities and get a team working on a way … to allow access for technicians to enter in order to make the necessary repairs.”

As Lindsey and his personnel were developing a plan, there was a critical loss of pressure at Launch Complex 41 “and technicians had to get to (OSIRIS-REx) immediately.”

With assistance from Kennedy Space Center, a response team from the 45th Space Wing was able to circumvent the site of the explosion, get to Launch Complex 41 and save OSIRIS-REx, Lindsey said.

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    $\begingroup$ Distance between SLC-40 (Falcon 9) and 41 (Osiris-Rex) is 2.5 km. $\endgroup$ – Hobbes Sep 16 '16 at 10:00
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    $\begingroup$ @Hobbes thanks - so I wonder about the choice of words "adjoining facility". $\endgroup$ – uhoh Sep 16 '16 at 10:43
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SLC-40 and 41 are neighbors, no other pads in between. Some debris landed further away than SLC-41. They share some systems, e.g. the deluge system.

The only good source I've found is this post by a member of the emergency response team.

On Sept. 1, OSIRIS-REx was still in the vertical integration building next to the launch pad.

The explosion triggered the deluge system. The ERT worried the system might empty its storage, running the pumps dry. This could damage the pumps and make a launch from SLC-41 impossible.

The post also mentions the chillers, but offers no detail. I've got confirmation this was about the climate control system for the payload. The spacecraft was undergoing tests and was powered up. As it was already inside the fairing, that power/heat went into a small enclosed volume, so they run an AC to blow cold air into the fairing.

The cause of the chiller failure may have been something simple like a power failure (either due to blast effects, or a precautionary shutdown after the explosion).

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    $\begingroup$ So it's possible in the re-telling of the fact that that the earliest possible launch date might have been missed, the possible repercussions became more serious than the reality. The launch window is quite wide for this mission, so there might even be time to fix the deluge pumps. "The OSIRIS-REx launch window opens on September 8, 2016. The launch period will last for 34 days, with a 120 minute window available each day." I don't think there is an RTG to be cooled, and no cryogenics on board the satellite, so the issue of coolant is unresolved. $\endgroup$ – uhoh Sep 16 '16 at 15:14
  • $\begingroup$ @uhoh: OSIRIS-REx was powered up for testing. Electronics generate heat. Lots of heat. (That's why your computer needs powerful fans to keep it from melting.) $\endgroup$ – Sean Jul 5 at 22:34
  • $\begingroup$ @Sean I'd expect that the spacecraft under test would be cooled by a closed-loop chiller. 1, 2, 3 It's the connection between the closed loop of the cooling system for the electronics, and the launch pad deluge system that has me stymied. $\endgroup$ – uhoh Jul 5 at 22:53
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Satellites are finely tuned to work in a specific environment. Space is a tough environment, but usually pretty consistent. One of the things required is to keep the spacecraft at a certain operating temperature at all times, including on the ground and on the rocket. There are a few components that are particularly sensitive, most notably the batteries. Depending on the state of integration, the satellite might have been set such that it was continually running, which is something required prior to launch in remove before flight operations. If that had happened, then the satellite was being used in the tightened environment pre-launch, which could cause some heating issues.

The incident may or may not have been directly related to the issue, but access to the integration facility was clearly limited being so close to the scene of the accident, and that took what might have been fairly minor problem and compounded it.

I doubt that OSIRIS-REX would have been a complete waste if the temperature had gone in to the red lines, but it's performance might have been in question, particularly for any eclipse periods that the spacecraft will enter.

I suspect that when the incident happened, the entire area was evacuated. The kinds of measurements that are required to determine if there is a problem are routinely monitored, particularly when the launch is so close.

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    $\begingroup$ OK that make a lot of sense. I was imagining it was just sitting there "turned off" and waiting to launch, but it makes much more sense that it could be powered up, maybe even under active testing. In any case it would be surrounded by >293K blackbody radiation rather than space and might need supplemental cooling to avoid overheating. $\endgroup$ – uhoh Sep 16 '16 at 15:29
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    $\begingroup$ Active testing was less likely, but it could be under active management is quite likely. If it was under active testing, I'm sure they would have stopped the testing very quickly if at all possible, which usually is for any kind of ground testing. $\endgroup$ – PearsonArtPhoto Sep 16 '16 at 16:21

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