Comments on: Hubble ACS, We Hardly Knew You

Hubble ACS, We Hardly Knew You

Brak — Mon, 29 Jan 2007 20:22:39 -0800

Hubble's ACS Has Died. Hubble's Advanced Camera for Surveys has apparently gone into safe mode, with little hope of return. The ACS was installed in 2002, and added amazing upgrades to Hubble's imaging capabilities. Though its lifespan was only projected at five years, scientists had hoped it would hold out longer. Though a final shuttle servicing mission is scheduled for 2008, the mission objectives plate is already too full to consider its repair. Alas, more of those beautiful pictures (as well as extended research capabilities) will have to wait until the James Webb Space Telescope is launched in 2013.

By: fandango_matt

fandango_matt — Mon, 29 Jan 2007 20:29:56 -0800

By: furtive

furtive — Mon, 29 Jan 2007 20:39:59 -0800

By: brain cloud

brain cloud — Mon, 29 Jan 2007 20:50:16 -0800

@__ (runaway galaxy)

By: BeerFilter

BeerFilter — Mon, 29 Jan 2007 20:52:50 -0800

Someone ask the Chinese to put the ol' boy down.

By: anthill

anthill — Mon, 29 Jan 2007 20:56:08 -0800

By: Blazecock Pileon

Blazecock Pileon — Mon, 29 Jan 2007 20:58:27 -0800

§ (spiral galaxy)

By: pinespree

pinespree — Mon, 29 Jan 2007 21:20:31 -0800

. (would have looked more like a galaxy and less like a dot through the ACS)

By: delmoi

delmoi — Mon, 29 Jan 2007 21:47:23 -0800

I think Jim Webb is a pretty cool Senator too, but it seems a little early to name a space telescope after him...

By: cenoxo

cenoxo — Mon, 29 Jan 2007 22:02:12 -0800

The Hubble Ultra Deep Field — 10,000 galaxies in an area 1/50th the diameter of the full Moon (1/12,700,000th of the entire sky), taken during 400 orbits with a total exposure time of about 1,000,000 seconds. That was some shootin'.

By: zamboni

zamboni — Mon, 29 Jan 2007 22:17:02 -0800

That first paragraph in the lead article is confusing. Hubble went into safe mode, for about 18 hours, then came back up. ACS isn't in safe mode, it's just stuffed. They're looking at switching back to its primary electronics package, to see if they can restore some functionality.
In any event, next year's service mission should install Wide Field Camera 3, so we can have lots of pretty pictures again.

By: mr_roboto

mr_roboto — Mon, 29 Jan 2007 22:54:26 -0800

zamboni writes "In any event, next year's service mission should install Wide Field Camera 3, so we can have lots of pretty pictures again." Yeah, it's my understanding that this new camera will fill many of the gaps created by the death of the ACS. And Hubble still has two cameras among it's current instrument set: NICMOS and WFPC2. So it can still take pretty pictures.

By: delmoi

delmoi — Mon, 29 Jan 2007 23:27:33 -0800

So are they going to replace the gyroscopes? I remember reading a couple of years ago that it was on it's last legs due to dying gyroscopes or something.

By: pruner

pruner — Mon, 29 Jan 2007 23:28:46 -0800

∞

By: mr_roboto

mr_roboto — Mon, 29 Jan 2007 23:30:49 -0800

delmoi writes "So are they going to replace the gyroscopes? I remember reading a couple of years ago that it was on it's last legs due to dying gyroscopes or something." Yeah, they changed their minds about that. There's going to be a mission to service the 'scope in 2008, and that includes replacing the gyroscopes.

By: NinjaTadpole

NinjaTadpole — Tue, 30 Jan 2007 02:11:45 -0800

æ (entwined spirals)

By: Mitrovarr

Mitrovarr — Tue, 30 Jan 2007 02:18:16 -0800

Does anyone still think the James Webb telescope will actually be launched? I suspect it will become a victim of the Republican War on Science, along with the flaming wreck of NASA and our spaceflight programs.

By: Smart Dalek

Smart Dalek — Tue, 30 Jan 2007 03:59:08 -0800

By: eriko

eriko — Tue, 30 Jan 2007 05:47:57 -0800

Fuck Fuck Fuckkity Fuck Fuck. We don't have anything ready to replace ACS. The Wide Field Camera 3 is going to replace WFPC2, and the Cosmic Origins Spectrograph is slated to fill the bay where COSTAR currently sits¹ The problem? WFPC2 is "Wide Field *and* Planetary Camera 2". WFC3 is "Wide Field Camera". Notice something missing? Angular resolution. ACS has a wide field camera, but it also has a high resolution camera. WFC3 will have a wider field camera², but nothing with high angular resolution. Why? Because with ACS, they already had that, so they wanted something with an even wider field of few and a wider viewing bandwidth. WFC3 is a good camera, and I'm glad that SM4 is back on the manifest. But WFC3 was built as a compliment to ACS, not a replacement, and losing ACS is a bad blow -- it means that we've lost all of Hubble's zoom lenses. ACS replaced FOC -- the Faint Object Camera -- which was HST's former long lens. Hopefully, they'll be able to either resolve this, or possibly work a fix into the Service Mission. I doubt they can replace it -- even if they had a spare instrument, or could get one built before launch, the SM Manifest is already crowded -- two instrument swap, a repair to STIS, gyroscope swaps, power supply, FGS swaps, and a host of small details -- so even if another package is ready, they might not have the time to install it. 1) COSTAR was the corrective optics that refocused the image onto the other instruments. However, as those instruments were replaced, they came with their own corrective optics, and after Service Mission 3B, there wasn't anything left using COSTAR, so they're going to pull it out and replace it with an instrument. 2) They were going to swap roles. Currently, ACS is the survey camera, and WFPC2 the detailed imaging camera. After the swap, WFC3 would become the survey camera, and ACS the detailed imaging camera.

By: Anything

Anything — Tue, 30 Jan 2007 10:26:51 -0800

# (Q-net)

By: pombe

pombe — Tue, 30 Jan 2007 12:08:09 -0800

Much much more about ACS at its home page.

By: dhartung

dhartung — Tue, 30 Jan 2007 12:57:42 -0800

Note that Webb (which is named for a former NASA administrator, not the Senator, or the cake-in-the-rain guy) is an infrared-based telescope. It's not designed for pretty pictures, despite tremendous science capability, and is not a replacement for Hubble. Apparently the electronics for ACS are inaccessible without removing the entire package, one reason there is probably no chance of working a fix into the schedule.

By: mhh5

mhh5 — Tue, 30 Jan 2007 13:46:06 -0800

Didn't NASA make a backup for every satellite it made? Is there a mothballed Hubble 2 sitting in a warehouse somewhere? Anyone have an idea what the cost would be to replace Hubble with an exact replica? (versus the cost of a mission to fix it?)

By: neckro23

neckro23 — Tue, 30 Jan 2007 15:09:48 -0800

"Didn't NASA make a backup for every satellite it made?" Is there a mothballed Hubble 2 sitting in a warehouse somewhere? Considering that Hubble's manufacture required the grinding of the largest, highest-precision telescope mirror ever made, no. (Actually, there was a backup mirror made, which is apparently now on display in the Smithsonian.)