Nasa reveals bursting habitat that created boom in Houston in July
On 9 July, a loud boom resounded around the Houston Texas area around Johnson Space Center, and Nasa has now released footage of the test that caused the sound.
In a post on the social media network Twitter, Johnson Space Center revealed footage of a burst pressure test of an inflatable habitat prototype, an armoured membrane that could be inflated in Earth orbit to serve as a space station module, or on the Moon as part of a future Moon base.
In a burst pressure test, engineers inflate a pressure vessel to the point where it bursts. This helps them understand both the extreme safety limits of the pressure vessel and may help in the design process.
In this case, the pressure vessel was a prototype of the Large Integrated Flexible Environment, or Life habitat being developed by Colorado-based Sierra Space. Life habitats are constructed of the same tough, Vectran fibers used in the landing airbags for Nasa's Spirit and Opportunity Mars rovers, and at 27-feet in diameter, offer about 984 cubic feet of interior volume[*], according to the Sierra Space Website.
During the July pressure burst test, a one-third scale Life habit was inflated to an internal pressure of 192 pounds per square inch (PSI), according to a Sierra Space tweet about the test. That exceeded the safety requirement of 182.4 PSI, the company noted.
[*] 300 cubic meters of pressurized volume (about 1/3 the pressurized volume on the international space station)
(Score: 0) by Anonymous Coward on Monday September 19 2022, @02:10PM (4 children)
984 cubic feet is 27.8 cubic metres.
(Score: 2) by hendrikboom on Monday September 19 2022, @03:50PM (2 children)
Looks like someone converted the feet to metres without noticing the 'cubic'.
(Score: 1) by Runaway1956 on Monday September 19 2022, @04:54PM (1 child)
Well, I come up with 36 cubic yards for 984 cu ft, 27 cu ft per cu yard. Google says that 36 cubic yards = 27.524 cubic meters. What did Grandparent poster and I both miss?
(Score: 2) by hendrikboom on Monday September 19 2022, @11:14PM
You two didn't miss it. The footnote in the summary did.
(Score: 2) by takyon on Monday September 19 2022, @04:39PM
https://www.sierraspace.com/space-destinations/life-space-habitat/#:~:text=300%20cubic%20meters%20of%20pressurized%20volume%20(about%201/3%20the%20pressurized%20volume%20on%20the%20international%20space%20station) [sierraspace.com]
https://mobile.arc.nasa.gov/public/iexplore/missions/pages/solarsystem/iss.html#:~:text=ISS%20has%20an%20internal%20pressurized,that%20of%20a%20Boeing%20747. [nasa.gov]
Blame journo.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by Immerman on Monday September 19 2022, @02:11PM (5 children)
Glad to see inflatable habitat modules *finally* getting some of the love they deserve with the new Orbital Reef space station.
As I recall from other sources that don't require an account - this was a planned test to destruction, and the failure pressure was dramatically higher than the design requirements, which bodes well for their deployment.
(Score: 4, Interesting) by JoeMerchant on Monday September 19 2022, @02:44PM (4 children)
This was a "will it blend" type of destructive test... we're going to keep going until it fails no matter what.
192psi sounds to me like it's 182.4psi ABOVE nominal service pressure on duty.
Much MUCH more impressive, to me, would be operating the hab around 30psig (say, 3ish ATA) for years at a time, baking in the Houston sun, being pelted by simulated micrometeorites, etc.
I can picture a space station where they have a dozen of these inflated hab structures, with two dozen more in storage. When one has a problem, you just recover the resources: equipment, atmosphere (and people) from inside, detach and de-orbit it - preferably in a capsule designed to incinerate itself and its contents upon re-entry, and replace it with one of the spares. If they can get even 5 years MTBF, that's one balloon replacement per 5 months on average with the capability to replace them all before a re-supply arrives in the event of a catastrophic event (comet tail pebble shower?) that sends everyone into the hard-structure until the mess can be cleaned up.
🌻🌻 [google.com]
(Score: 2) by takyon on Monday September 19 2022, @04:41PM (3 children)
They can predict the rate at which it gets pelted by smaller micrometeorites. It needs to be able to withstand unusually powerful impacts.
They should ask Texans to shoot at it.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by PiMuNu on Monday September 19 2022, @05:50PM (2 children)
Actually, typical small firearms muzzle velocity is a couple of orders of magnitude too low.
Worth also saying that ISS is not immune to meteorite impacts. The question is rather how large impact can be withstood.
A "worst case" scenario, they can inflate a sacrificial shield in front of the habitat to destroy most meteorites.
(Score: 3, Interesting) by JoeMerchant on Monday September 19 2022, @06:44PM (1 child)
The question is: what does that sacrificial shield contain? My vote if I were living there: water, inside a self-healing membrane.
A couple of the challenges are: a 1 gram pebble moving at 20kmph is going to need a lot of mass to drag its speed down to something safe. Also: gamma rays and similar have a nasty habit of multiplying their ionizing potential when passing through moderate mass shields. Thin shields (like the current ISS walls) rarely intercept the gamma rays so they just pass through, but at moderate mass (like 1cm of lead) Compton scattering means that the gamma ray spawns a number of lower energy, but still highly ionizing, particles - making the radiation worse than no shield at all. However, in most normal "space weather" several meters of water is enough to stop the spawned particles too...
🌻🌻 [google.com]
(Score: 2) by PiMuNu on Tuesday September 20 2022, @10:51AM
The aim is to destroy the pebble rather than slow it down. At such high velocity, even a moderate barrier can destroy stuff.
https://en.wikipedia.org/wiki/Whipple_shield [wikipedia.org]