James Webb Telescope Hit By Large Micrometeoroid (theverge.com) 50
schwit1 shares a report from The Verge: NASA's new powerful space observatory, the James Webb Space Telescope (JWST), got pelted by a larger than expected micrometeoroid at the end of May, causing some detectable damage to one of the spacecraft's 18 primary mirror segments. The impact means that the mission team will have to correct for the distortion created by the strike, but NASA says that the telescope is "still performing at a level that exceeds all mission requirements."
Engineers do have the capability to also maneuver JWST's mirror and instruments away from showers of space debris, if NASA can see them coming. The problem, though, was that this micrometeoroid was not part of a shower, so NASA considers it an "unavoidable chance event." Still, the agency is forming an engineering team to come up with ways to potentially avoid or lessen the effects of micrometeoroid strikes of this size. And since JWST is so sensitive, the telescope will also help NASA get a better understanding of just how many micrometeoroids there are in the deep space environment.
Despite the strike, NASA remained optimistic in its post about JWST's future. "Webb's beginning-of-life performance is still well above expectations, and the observatory is fully capable of performing the science it was designed to achieve," according to the blog. Engineers can also adjust the impacted mirror to help cancel out the data distortion. The mission team has done this already and will continue to tinker with the mirror over time to get the best results. It's a process that will be ongoing throughout JWST's planned five to 10 years of life as new observations are made and events unfold. At the same time, NASA warns that the engineers will not be able to completely cancel out the impact of the strike.
Engineers do have the capability to also maneuver JWST's mirror and instruments away from showers of space debris, if NASA can see them coming. The problem, though, was that this micrometeoroid was not part of a shower, so NASA considers it an "unavoidable chance event." Still, the agency is forming an engineering team to come up with ways to potentially avoid or lessen the effects of micrometeoroid strikes of this size. And since JWST is so sensitive, the telescope will also help NASA get a better understanding of just how many micrometeoroids there are in the deep space environment.
Despite the strike, NASA remained optimistic in its post about JWST's future. "Webb's beginning-of-life performance is still well above expectations, and the observatory is fully capable of performing the science it was designed to achieve," according to the blog. Engineers can also adjust the impacted mirror to help cancel out the data distortion. The mission team has done this already and will continue to tinker with the mirror over time to get the best results. It's a process that will be ongoing throughout JWST's planned five to 10 years of life as new observations are made and events unfold. At the same time, NASA warns that the engineers will not be able to completely cancel out the impact of the strike.
Frightingly common (Score:4, Interesting)
Saw pictures of the replaced solar panels of the hubble telescope, they had been hit quite a bit too, one strike even passing through.
Re:Frightingly common (Score:4, Informative)
Depends where you put something. Hubble is in a fairly low Earth orbit where you'd expect more meteor hits. Webb is orbiting the sun at a lagrange point, which will also tend to collect debris -- not sure if more or less than Hubble's orbit. Geostationary orbit would be far less impacted, and interplanetary missions even less.
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Actually the Lagrange point that Webb is located at is inherently unstable, so it can be expected that less material is located there than elsewhere. In gravitational terms, think of it like trying to balance on a saddle rather than in the bottom of a cup.
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Re: Frightingly common (Score:4, Interesting)
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You mean relative speeds. Relativistic speeds are a bit more than a puny 0.003% of the speed of light.
We can have fun with GNU units to see what happen if that paint chip were moving at relativistic speeds. Since e=mc^2:
You have: (.01 in)^3 * 2g/ml * c^2
You want: kg tnt
* 638.67014
It looks like such an impact would have enough energy to completely obliterate the shuttle.
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I wasn't trying to determine whether that paint chip was actually relativistic; obviously, it wasn't. I just wanted to find out what would happen if there *were* such a thing as a paint chip traveling near the speed of light.
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When those SF authors introduced
Nooooooooo (Score:4, Interesting)
Collective sigh of relief breathed, it took long enough just getting the **** thing up there.
Space is dirty, maybe this is why we don't get alien visits.
Re:Nooooooooo (Score:5, Funny)
Space is dirty, maybe this is why we don't get alien visits.
You'd think all those dust particles would get picked up by the vacuum. :-)
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Accident? (Score:3)
You think this was an accident? Somebody out there doesn't want us to see something - or maybe just needed more time to cloak properly... ;)
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Nah, it's the deflector shield that should be deflecting the dust and small meteoroids. /joke
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More and bigger to come (Score:4, Insightful)
Despite the strike, NASA remained optimistic
JWST has only been in place for a few months. It is impossibly unlikely that this will be the biggest meteorite to hit it during its (up to) 10 year operational life. If each additional hit distorts a mirror panel, that could be what ends the telescope's usefulness, not running out of propellant. And it is something that nobody can make any proper predictions about, since there is so little data on meteorite incidence at the L2 point
Re:More and bigger to come (Score:5, Informative)
While we don't know about the stuff passing through, we at least know that an unstable equilibrium point like L2 isn't going to be accumulating detritus that hangs around.
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You can certainly make that argument, but you'd be very well advised to carry out experiments to check that the universe agrees with your logic.
Which is precisely why most space probes have carried dust-strike detectors - at least for the interplanetary cruise phase - since the 1960s. It's not as if people don't plan for these things, against an observational basis.
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The number of, and duration of, missions is probably less important than the range of trajectories in the early days of the mission (corollary - the "dust impact sensor" is one you want tu turn on early, possibly before the aerodynamic faring comes off). But yeah, experimental data is needed, and the day that "more data" isn't really helpful is probably a long way off. If the sensor is light, and low power, and off-the-shelf (part of the reference design for the transport bus that mates the custom
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The L2 point is at an unstable equilibrium so any objects stationary to
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Yes, that's a standard calculation when you're studying planet building.
Umm, I think you mean "roughly co-planar orbital planes", but yeah, for the inner solar system. Of course, not all particles in the inner solar system (today) are on inner solar system -like orbits. Debris from comets, collisions, etc can be on almost a
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Re:More and bigger to come (Score:5, Informative)
Depending on your definition of moon, there are. They're called trojans [wikipedia.org]; Jupiter has thousands, and Earth has a couple. There are also orbital bodies which bounce between the two, of which Earth's horseshoe librator Cruithne is probably the most famous.
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They are only stable on the order of a few million years, as the perturbations from the gravity of other objects in the solar system is eventually large enough to break the orbit.
Re:More and bigger to come (Score:5, Insightful)
If it's been in place for 2.5% of its (longest projected) operational life, the chances that it's already been hit by the largest thing which will hit it are roughly 2.5%. That's not "impossibly unlikely".
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Send in Spaceforce (Score:3, Funny)
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Ed White was Texan and he was the first American to spacewalk. David Scott was also Texan and he was an Apollo astronaut who walked on the moon.
Large micrometeoroid? (Score:5, Funny)
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Ha, nice. Beat me to it by 4 minutes.
And if I had seen it, I wouldn't have posted it (below).
[...golf clap...]
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Well, the same as JWST getting hit by dust, apparently.
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A large micrometeroid the size of a small micrometeroid.
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Evidently the milli-funny impacts are Poisson events? Only separated by 4 minutes even though the story had been published over an hour earlier.
Or is there a conspiracy here? You and fahrbot-bot arranged the coincidence?
Large Micrometeoroid? (Score:3, Funny)
So... a millimeteoroid?
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I was going to say "minimeteoroid" but yeah, the headline is lulz.
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Four-minute separation between impacts, but maybe there were other millijokes that the Funny moderators did not detect?
(Though most of the attempted jokes on Slashdot these days would rate as microjokes.)
(But that thought reveals the obvious search...)
So in reality a macrometerite? (Score:3)
Like all big micros?
mini maxi milli vanilli small large micrometeroid (Score:2)
can anyone pintpoint what unexpect expected mini maxi milli vanilli macro small large micrometeroid with a no impact impact that causes no noticable effect that will need to be compensated is? asking for a friend :p
'Tis but a scratch! (Score:2)
The 107" scope at McDonald Observatory has bullet holes.
http://pages.astronomy.ua.edu/... [ua.edu]
Shroud? (Score:2)
This may be a silly question but would a shroud have helped? I don't recall ever hearing that Hubble had this issue, but it basically has a shroud (tube) around it that limits the exposure from incoming micrometeoroids to a much smaller solid angle than JWST. But then again it would be one hell of a shroud for JWST. And it would have to be thick enough to actually stop the micrometeoroid.
so...let's see here... (Score:2)
We spent decades designing an uber-expensive exotic fragile scientific instrument, which we planned to put in a place we'd never put one before (so we guessed at the hazards of using the location (this particular Lagrange point) this way, and also we knew full-well that humans sometimes fail at tasks and manufacture things with flaws (see:Hubble Space Telescope) and sometimes blow rockets up, by things like getting arrogant and launching them outside of their design constraints (see: Challenger), thus losin
Large micrometeroid? (Score:2)
"unavoidable chance event." (Score:1)
I heard that meteor strikes are common this month and every November because we pass through some kind of belt.
Can you help me find the name for this to fact check it?