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Posted by: deglr6328 Oct 14 2005, 05:01 AM

How much cryogen does Spitzer have remaining in its dewar? Do they know, or are they just waiting to see a temperature rise after complete boil-off? Can't find much info on the website.

Posted by: DEChengst Nov 9 2005, 10:13 PM

Don't know about the current estimate, but during launch the helium was estimated to last until 2008 or 2009.

Posted by: deglr6328 Nov 10 2005, 08:01 AM

wow, weird that GP-B's only lasted a single year an had like 8 times the total volume.

Posted by: djellison Nov 10 2005, 09:44 AM

But GP-B had to be kept a lot lot colder than Spitzer does.

Doug

Posted by: deglr6328 Nov 10 2005, 10:11 AM

mmmnah same temp I think. http://www.spitzer.caltech.edu/technology/cryostat.shtml at ~1.5K. Right? Perhaps the cold volume in Spitzer is just less massive than GP-B's "science package". Or maybe GP-B just has to deal with more thermal radiation from Earth since it's in LEO. In fact, yes, now that I think about it I'd be willing to bet this is the reason the He ran out so much faster on GP-B.

Posted by: djellison Nov 10 2005, 10:30 AM

Nope - you're right - same temp. - for some reason I thought Spitzer was kept a bit warmer than GPB

The LEO issue is almsot certainly a clincher though -

Posted by: tfisher Nov 10 2005, 03:59 PM

You nailed that one on the head. Here's what http://www.spitzer.caltech.edu/about/orbit.shtml has to say:

Posted by: hendric Nov 10 2005, 10:29 PM

Will Spitzer be useful once the Helium runs out?

Posted by: Circum Nov 10 2005, 10:37 PM

Keep in mind that some of GPB's helium was used to spin up the gyros and also for the micro-thrusters, although I admit I'm not sure of the volumes used for those purposes relative to cooling.

Posted by: deglr6328 Nov 12 2005, 02:48 AM

That's an interesting thought. If it ends up equilibrating at 30-40K after He boiloff I could imagine it still getting some useful data from the shorter wavelength IRAC sensors at ~3-5 microns. I should think that the noise wouldn't be too high to prevent some imaging in that band. hmmm. But then this is barely above the range of the Hubble NICMOS and you'd have the question of whether or not it would be economically worth it. (well, assuming that Hubble is still operating of course)

What I don't get is if it has such an incredibly low boiloff rate to begin with (something like a few milliliters per hour) why wouldn't they look at attaching something like http://www.quantum-technology.com/web/Helium%20MRI%20Reliquefiers.htm to reliquefy some of the helium? I would think that even with a modest investment in power from larger solar arrays (say.... 1 KW) you could easily double the mission lifetime by reducing the boiloff rate, if not eliminating it completely.

Posted by: ljk4-1 Dec 5 2005, 05:15 PM

Spitzer Space Telescope article in December, 2005 issue of National Geographic Magazine.

There's a lot hiding in the universe's dark corners. Interstellar dust clouds and inky stretches of deep space can appear dull to ordinary telescopes. But to a car-size telescope 26 million miles (42 million kilometers) from Earth, they are alive with light—infrared light, or heat rays. Since its launch in August 2003, says Robert Kennicutt, an astronomer at the University of Arizona, NASA's Spitzer Space Telescope "has opened up half the universe to us."

In the process, it has exposed cosmic birthplaces. Stars take shape in clouds of gas and dust, and planets emerge in disks of debris around new stars. Early galaxies are also swathed in dust. Little visible light gets out, but these objects still emit heat—and infrared.

http://www7.nationalgeographic.com/ngm/0512/feature5/index.html

Posted by: ljk4-1 Jan 16 2006, 08:23 PM

Astrophysics, abstract
astro-ph/0511358

From: William T. Reach [view email]

Date (v1): Fri, 11 Nov 2005 16:32:59 GMT (59kb)
Date (revised v2): Thu, 17 Nov 2005 07:43:56 GMT (0kb,I)
Date (revised v3): Thu, 17 Nov 2005 21:57:35 GMT (0kb,I)
Date (revised v4): Fri, 13 Jan 2006 18:04:39 GMT (59kb)

The Dust cloud around the White Dwarf G 29-38

Authors: William T. Reach, Marc J. Kuchner, Ted von Hippel, Adam Burrows, Fergal Mullally, Mukremin Kilic, D. E. Winget

Comments: accepted for publication in the Astrophysical Journal Letters

Journal-ref: 2005, Astrophysical Journal Letters, volume 635, page L161

We present new observations of the white dwarf G 29-38 with the camera (4.5 and 8 microns), photometer (24 microns), and spectrograph (5.5-14 microns) of the Spitzer Space Telescope. This star has an exceptionally large infrared excess amounting to 3% of the bolometric luminosity. The spectral energy distribution has a continuum peak around 4.5 micros and a 9-11 micron emission feature 1.25 times brighter than the continuum. A mixture of amorphous olivine and a small amount of forsterite in an emitting region 1-5 Rsun from the star can reproduce the shape of the 9-11 micron feature. The spectral energy distribution also appears to require amorphous carbon to explain the hot continuum. Our new measurements support the idea that a relatively recent disruption of a comet or asteroid created the cloud.

http://arxiv.org/abs/astro-ph/0511358

Posted by: ljk4-1 Jan 24 2006, 07:15 PM

Astrophysics, abstract
astro-ph/0601495

From: Patrice Bouchet J.. [view email]

Date: Mon, 23 Jan 2006 01:45:09 GMT (761kb)

SN 1987A After 18 Years: Mid-Infrared GEMINI and SPITZER Observations of the Remnant

Authors: Patrice Bouchet, Eli Dwek, I. John Danziger, Richard G. Arendt, I. James M. De Buizer, Sangwook Park, Nicholas B. Suntzeff, Robert P. Kirshner, Peter Challis

Comments: 23 pages; 3 tables; 12 figures (Fig.2, Fig.4, and Fig.7 missing because too big; Fig.14 is provisory); submitted to ApJ January 2006

We present high resolution 11.7 and 18.3um mid-IR images of SN 1987A obtained on day 6526 with T-ReCS attached to the Gemini telescope. The 11.7um flux has increased significantly since our last observations on day 6067. The images clearly show that all the emission arises from the equatorial ring (ER). Spectra obtained with Spitzer, on day 6184 with MIPS at 24um, on day 6130 with IRAC in the 3.6-8um region, and on day 6190 with IRS in the 12-37um region show that the emission consists of thermal emission from silicate dust that condensed out in the red giant wind of the progenitor star. The dust temperature is ~166K, and the emitting dust mass is ~2.6 x 10-6 Msun. Lines of [Ne II]12.82um and [Ne III]15.56um are clearly present, as well as a weak [Si II]34.8um line. We also detect two lines near 26um which we tentatively ascribe to [Fe II]25.99um and [O IV]25.91um. Comparison of the Gemini 11.7um image with X-ray images from Chandra, UV-optical images from HST, and radio synchrotron images obtained by the ATCA show generally good correlation of the images across all wavelengths. Because of the limited resolution of the mid-IR images we cannot uniquely determine the location or heating mechanism of the dust giving rise to the emission. The dust could be collisionally heated by the X-ray emitting plasma, providing a unique diagnostic of plasma conditions. Alternatively, the dust could be radiatively heated in the dense UV-optical knots that are overrun by the advancing supernova blast wave. In either case the dust-to-gas mass ratio in the circumstellar medium around the supernova is significantly lower than that in the general ISM of the LMC, suggesting either a low condensation efficiency in the wind of the progenitor star, or the efficient destruction of the dust by the SN blast wave.

http://arxiv.org/abs/astro-ph/0601495

Posted by: ljk4-1 Jan 30 2006, 07:13 PM

Paper: astro-ph/0601633

Date: Fri, 27 Jan 2006 02:44:00 GMT (226kb)

Title: Spectacular Spitzer images of the Trifid Nebula: Protostars in a young,
massive-star-forming region

Authors: J. Rho, W. T. Reach (Spitzer Science Center/CalTech), B. Lefloch
(Laboratoire d'Astrophysique, Observatoire de Grenoble) and G. Fazio
(Harvard-Smithsonian Center for Astrophysics)

Comments: Accepted for publication in ApJ. Full resolution images are available
at http://spider.ipac.caltech.edu/staff/rho/
\\

Spitzer IRAC and MIPS images of the Trifid Nebula (M20) reveal its
spectacular appearance in infrared light, highlighting the nebula's special
evolutionary stage. The images feature recently-formed massive protostars and
numerous young stellar objects, and a single O star that illuminates the
surrounding molecular cloud from which it formed, and unveil large-scale,
filamentary dark clouds. The hot dust grains show contrasting infrared colors
in shells, arcs, bow-shocks and dark cores. Multiple protostars are detected in
the infrared, within the cold dust cores of TC3 and TC4, which were previously
defined as Class 0. The cold dust continuum cores of TC1 and TC2 contain only
one protostar each. The Spitzer color-color diagram allowed us to identify ~160
young stellar objects and classify them into different evolutionary stages. The
diagram also revealed a unique group of YSOs which are bright at 24 micron but
have the spectral energy distribution peaking at 5-8 micron. Despite
expectation that Class 0 sources would be "starless" cores, the Spitzer images,
with unprecedented sensitivity, uncover mid-infrared emission from these Class
0 protostars. The mid-infrared detections of Class 0 protostars show that the
emission escapes the dense, cold envelope of young protostars. The mid-infrared
emission of the protostars can be fit by two temperatures of 150 and 400 K; the
hot core region is probably optically thin in the mid-infrared regime, and the
size of hot core is much smaller than that of the cold envelope. The presence
of multiple protostars within the cold cores of Class 0 objects implies that
clustering occurs at this early stage of star formation. The TC3 cluster shows
that the most massive star is located at the center of the cluster and at the
bottom of the gravitational-potential well.

\\ ( http://arXiv.org/abs/astro-ph/0601633 , 226kb)

Posted by: ljk4-1 Feb 8 2006, 06:41 PM

News Release: 2006-019

February 8, 2006

NASA's Spitzer Uncovers Hints of Mega Solar Systems

NASA's Spitzer Space Telescope has identified two huge "hypergiant" stars circled by monstrous disks of what might be planet-forming dust. The findings surprised astronomers because stars as big as these were thought to be inhospitable to planets.

"These extremely massive stars are tremendously hot and bright and have very strong winds, making the job of building planets difficult," said Joel Kastner of the Rochester Institute of Technology in New York. "Our data suggest that the planet-forming process may be hardier than previously believed, occurring around even the most massive stars that nature produces."

Kastner is first author of a paper describing the research in the Feb. 10 issue of Astrophysical Journal Letters.

Dusty disks around stars are thought to be signposts for present or future planetary systems. Our own sun is orbited by a thin disk of planetary debris, called the Kuiper Belt, which includes dust, comets and larger bodies similar to Pluto.

Last year, astronomers using Spitzer reported finding a dust disk around a miniature star, or brown dwarf, with only eight one-thousandths the mass of the sun (http://www.spitzer.caltech.edu/Media/happenings/20051129/). Disks have also been spotted before around stars five times more massive than the sun.

The new Spitzer results expand the range of stars that sport disks to include the "extra large." The infrared telescope detected enormous amounts of dust around two positively plump stars, R 66 and R 126, located in the Milky Way's nearest neighbor galaxy, the Large Magellanic Cloud. Called hypergiants, these blazing hot stars are aging descendents of the most massive class of stars, referred to as "O" stars. They are 30 and 70 times the mass of the sun, respectively. If a hypergiant were located at the sun's position in our solar system, all the inner planets, including Earth, would fit comfortably within its circumference.

Astronomers estimate that the stars' disks are also bloated, spreading all the way out to an orbit about 60 times more distant than Pluto's around the sun. The disks are probably loaded with about ten times as much mass as is contained in the Kuiper Belt. Kastner and his colleagues say these dusty structures might represent the first or last steps of the planet-forming process. If the latter, then the disks can be thought of as enlarged versions of our Kuiper Belt.

"These disks may be well-populated with comets and other larger bodies called planetesimals," said Kastner. "They might be thought of as Kuiper Belts on steroids."

Spitzer detected the disks during a survey of 60 bright stars thought to be wrapped in spherical cocoons of dust. According to Kastner, R 66 and R 126 "stuck out like sore thumbs" because their light signatures, or spectra, indicated the presence of flattened disks. He and his team believe these disks whirl around the hypergiant stars, but they say it is possible the giant disks orbit unseen, slightly smaller companion stars.

A close inspection of the dust making up the disks revealed the presence of sand-like planetary building blocks called silicates. In addition, the disk around R 66 showed signs of dust clumping in the form of silicate crystals and larger dust grains. Such clumping can be a significant step in the construction of planets.

Stars as massive as R 66 and R 126 don't live very long. They burn through all of their nuclear fuel in only a few million years, and go out with a bang, in fiery explosions called supernovae. Their short life spans don't leave much time for planets, or life, to evolve. Any planets that might crop up would probably be destroyed when the stars blast apart.

"We do not know if planets like those in our solar system are able to form in the highly energetic, dynamic environment of these massive stars, but if they could, their existence would be a short and exciting one," said Charles Beichman, an astronomer at NASA's Jet Propulsion Laboratory and the California Institute of Technology, both in Pasadena.

Other authors of this work include Catherine L. Buchanan of the Rochester Institute of Technology, and B. Sargent and W. J. Forrest of the University of Rochester, N.Y.

The Jet Propulsion Laboratory manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at Caltech. JPL is a division of Caltech. Spitzer's infrared spectrograph, which made the new observations, was built by Cornell University, Ithaca, N.Y. Its development was led by Jim Houck of Cornell.

An artist concept of a hypergiant and its disk, plus additional graphics and information, are available at http://www.spitzer.caltech.edu/spitzer . For more information about NASA and agency programs on the Web, visit

http://www.nasa.gov/home/ .

Posted by: ljk4-1 Feb 8 2006, 06:47 PM

Astrophysics, abstract
astro-ph/0602146

From: Donald F. Figer [view email]

Date: Tue, 7 Feb 2006 02:14:43 GMT (381kb)

Discovery of an Extraordinarily Massive Cluster of Red Supergiants

Authors: Donald F. Figer (RIT), John MacKenty, Massimo Robberto, Kester Smith (STScI), Francisco Najarro (CSIC), Rolf P. Kudritzki (UH), Artemio Herrero (IAC)

Comments: ApJ, accepted

We report the discovery of an extraordinarily massive young cluster of stars in the Galaxy, having an inferred total initial cluster mass comparable to the most massive young clusters in the Galaxy. Using {\it IRMOS}, {\it 2MASS}, and {\it Spitzer} observations, we conclude that there are 14 red supergiants in the cluster, compared with five, in what was previously thought to be the richest Galactic cluster of such stars. We infer spectral types from near-infrared spectra that reveal deep CO bandhead absorption that can only be fit by red supergiants. We identify a gap of $\Delta${\it K}$_s$$\sim$4 magnitudes between the stars and the bulk of the other stars in the region that can only be fit by models if the brightest stars in the cluster are red supergiants. We estimate a distance of 5.8~\kpc to the cluster by associating an OH maser with the envelope of one of the stars. We also identify a ``yellow'' supergiant of G6~I type in the cluster. Assuming a Salpeter IMF, we infer an initial cluster mass of 20,000 to 40,000~\Msun for cluster ages of 7-12~\Myr. Continuing with these assumptions, we find 80% of the intial mass and 99% of the number of stars remain at the present time. We associate the cluster with an x-ray source (detected by {\it ASCA} and {\it Einstein}), a recently discovered very high energy $\gamma$-ray source (detected by {\it INTEGRAL} and {\it HESS}), and several non-thermal radio sources, finding that these objects are likely related to recent supernovae in the cluster. In particular, we claim that the cluster has produced at least one recent supernova remnant with properties similar to the Crab nebula. It is not unlikely to find such a source in this cluster, given our estimated supernova rate of one per 40,000 to 80,000~{\it yr}.

http://arxiv.org/abs/astro-ph/0602146

Posted by: Jeff7 Feb 8 2006, 10:14 PM

If it is determined that Spitzer is of no use once the liquid helium is gone, what's going to be done with it? Send it on a decaying orbit into the sun or just sort of leave it dormant where it's at?

Posted by: tty Feb 8 2006, 10:31 PM

Definitely not into the Sun. It requires an enormous Delta Vee to get there. The Sun is actually the most difficult place to reach in the Solar System, energy-wise.

tty

Posted by: Jeff7 Feb 8 2006, 10:43 PM

Really? Crazy....is that just because of outward inertia from the revolution around the sun?

Alright, how about smacking it into the Moon Deep-Impact style? Or else into Earth's atmosphere.

I guess I just don't like the idea of it hanging out there as little more than space junk.

Posted by: ljk4-1 Feb 8 2006, 11:41 PM

Could Spitzer be used as a "regular" telescope in some way? Does it have any other instruments that might perform, say solar and interplanetary observations?

Gravity Probe B can no longer perform its main function, but they are finding other uses for it as it is still active. I even recall the famous COBE satellite being used for some kind of satellite testing after it could no longer do major science work.

But let's not blast it from the skies like the USAF did to that poor satellite observing comets hitting the Sun, shall we?

http://heasarc.nasa.gov/docs/heasarc/missions/p78-1.html

http://cometography.com/lcomets/1979q1.html

http://www.svengrahn.pp.se/histind/ASAT/F15ASAT.html

http://www.edwards.af.mil/moments/docs_html/85-09-13.html

http://lasco-www.nrl.navy.mil/solwind.html

Regarding your "space junk" comment, some day those satellites still floating out in the void will be considered highly prized relics of the early Space Age by future exoarchaeologists.

Posted by: ljk4-1 Feb 15 2006, 08:14 PM

News Release: 2006-022 February 15, 2006

NASA's Spitzer Finds Violent Galaxies Smothered in 'Crushed Glass'

NASA's Spitzer Space Telescope has observed a rare population of colliding galaxies whose entangled hearts are wrapped in tiny crystals resembling crushed glass.

The crystals are essentially sand, or silicate, grains that were formed like glass, probably in the stellar equivalent of furnaces. This is the first time silicate crystals have been detected in a galaxy outside of our own.

"We were surprised to find such delicate, little crystals in the centers of some of the most violent places in the universe," said Dr. Henrik Spoon of Cornell University, Ithaca, N.Y. He is first author of a paper on the research appearing in the Feb. 20 issue of the Astrophysical Journal. "Crystals like these are easily destroyed, but in this case, they are probably being churned out by massive, dying stars faster than they are disappearing."

The discovery will ultimately help astronomers better understand the evolution of galaxies, including our Milky Way, which will merge with the nearby Andromeda galaxy billions of years from now.

"It's as though there's a huge dust storm taking place at the center of merging galaxies," said Dr. Lee Armus, a co-author of the paper from NASA's Spitzer Science Center at the California Institute of Technology in Pasadena. "The silicates get kicked up and wrap the galaxies' nuclei in giant, dusty glass blankets."

Silicates, like glass, require heat to transform into crystals. The gem-like particles can be found in the Milky Way in limited quantities around certain types of stars, such as our sun. On Earth, they sparkle in sandy beaches, and at night, they can be seen smashing into our atmosphere with other dust particles as shooting stars. Recently, the crystals were also observed by Spitzer inside comet Tempel 1, which was hit by NASA's Deep Impact probe

( http://www.spitzer.caltech.edu/Media/releases/ssc2005-18/release.shtml).

The crystal-coated galaxies observed by Spitzer are quite different from our Milky Way. These bright and dusty galaxies, called ultraluminous infrared galaxies, or "Ulirgs," are swimming in silicate crystals. While a small fraction of the Ulirgs cannot be seen clearly enough to characterize, most consist of two spiral-shaped galaxies in the process of merging into one. Their jumbled cores are hectic places, often bursting with massive, newborn stars. Some Ulirgs are dominated by central supermassive black holes.

So, where are all the crystals coming from? Astronomers believe the massive stars at the galaxies' centers are the main manufacturers. According to Spoon and his team, these stars probably shed the crystals both before and as they blow apart in fiery explosions called supernovae. But the delicate crystals won't be around for long. The scientists say that particles from supernova blasts will bombard and convert the crystals back to a shapeless form. This whole process is thought to be relatively short-lived.

"Imagine two flour trucks crashing into each other and kicking up a temporary white cloud," said Spoon. "With Spitzer, we're seeing a temporary cloud of crystallized silicates created when two galaxies smashed together."

Spitzer's infrared spectrograph spotted the silicate crystals in 21 of 77 Ulirgs studied. The 21 galaxies range from 240 million to 5.9 billion light-years away and are scattered across the sky. Spoon said the galaxies were most likely caught at just the right time to see the crystals. The other 56 galaxies might be about to kick up the substance, or the substance could have already settled.

Others authors of this work include Drs. A.G.G.M. Tielens and J. Cami of NASA's Ames Research Center, Moffett Field, Calif.; Drs. G.C. Sloan and Jim R. Houck of Cornell; B. Sargent of the University of Rochester, N.Y.; Dr. V. Charmandaris of the University of Crete, Greece; and Dr. B.T. Soifer of the Spitzer Science Center.

The Jet Propulsion Laboratory manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center. JPL is a division of Caltech. Spitzer's infrared spectrograph was built by Cornell University, Ithaca, N.Y. Its development was led by Dr. Jim Houck.

http://www.spitzer.caltech.edu/Media/releases/ssc2006-06/release.shtml

Posted by: ljk4-1 Feb 15 2006, 09:38 PM

Distant inferno: Cornell astronomer finds galaxies that contain massive young stars in compact, cosmic globs

http://www.news.cornell.edu/stories/Feb06/ULIRGs.Spoon.lg.html

Feb. 15, 2006

By Lauren Gold
lg34@cornell.edu

The discovery makes the fiery environment within a typical spiral or starburst galaxy look almost pastoral. Cornell researchers using the Spitzer Space Telescope say distant galaxies contain an inferno of very young, massive and violently evolving stars, packed together in tiny but extremely powerful cosmic globs.

The key to the discovery, paradoxically, is in the presence of delicate, glittery crystalline silicates called Forsterite. These are glassy particles that exist in the debris disks of young stars and in the stellar wind of very old stars, but which have never before been observed in the mass of gas and dust known as the interstellar medium, or ISM, in the Milky Way or in any other galaxy.

The research, led by Cornell astronomer and Spitzer Fellow Henrik Spoon, will appear in the Feb. 20 issue of the Astrophysical Journal.

Posted by: ljk4-1 Feb 22 2006, 08:06 PM

NASA's Spitzer Makes Hot Alien World the Closest Directly Detected

http://www.spaceref.com/news/viewpr.html?pid=19084

"A NASA-led team of astronomers have used NASA's Spitzer Space Telescope to
detect a strong flow of heat radiation from a toasty planet orbiting a nearby star.
The findings allowed the team to "take the temperature" of the planet."

Posted by: ljk4-1 Mar 22 2006, 12:33 PM

TIME AND SPACE

- Spitzer Sees Back 9 Billion Years

http://www.spacedaily.com/reports/Spitzer_Sees_Back_9_Billion_Years.html

Pasadena CA (SPX) Mar 21, 2006 - Astronomers have captured an image of the most
distant cluster of galaxies ever seen, located about 9 billion light-years away
from Earth – and photographed at a stage when the universe was only about
one-third of its present age.

Posted by: ljk4-1 May 15 2006, 02:49 PM

Review: The Last of the Great Observatories
---

The scientific work involved with a major NASA mission can pale in
comparison to the effort needed to actually build the spacecraft.

Jeff Foust reviews a new book that provides an insider's account of
the development of the Spitzer Space Telescope.

http://www.thespacereview.com/article/620/1

Posted by: Analyst Oct 13 2006, 10:32 AM

http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/39803/1/06-1464.pdf presentation says the LHe will last approx. 5 1/2 years, much longer than needed (2 1/2 years) for mission success and a little longer than the 5 years hoped for. There is also a possible extended "warm" mission mentioned.

Analyst

Posted by: mps May 7 2009, 12:18 PM

http://www.nasa.gov/mission_pages/spitzer/news/spitzer-20090506.html

Posted by: MahFL May 7 2009, 12:42 PM

Can anyone tell us how long Spitzer might operate for in its "warm" mission ?

Posted by: stevesliva May 7 2009, 04:31 PM

I'm not sure how long the current funding lasts, but that's probably the primary determinant: funding. The cost of operating Spitzer for just these two channels was not viewed by everyone as worthy of the cost. They did reduce operating expenses a bunch, but I think they were pressed to get operating costs down even farther. I'd guess they might get pressed harder the next go-around. And so it goes. Up to the hopefully well-advised beancounters.

This site has some great info on what they plan to do:
http://ssc.spitzer.caltech.edu/mtgs/warm/

Posted by: NGC3314 May 18 2009, 02:22 PM

They do get advice from (in this case) a panel of astrophysicists (I've done it but not this round). This one was brutal - continuation of Chandra operations, the Spitzer warm mission, continuation of GALEX, WMAP, Swift, RXTE... were all on the table for competitive review. (Hubble seems to have been a separate budget line). The usual pattern is to try to keep missions going past their nominal lifetimes if healthy and productive, with the budget squeeze getting tighter and tighter the longer they go on. When one of the ongoing (extended) missions has a glitch, you can practically hear the knives come out at NASA headquarters, not to mention the operations centers of all the others.

Current funding is supposed to be for two years of warm operation, which keeps the two shortest wavelengths with the Infrared Array Camera going with almost no degradation (including some impressive survey programs). Since the helium ran out on May 15 (two weeks after a recent estimate), the funded warm mission starts now.

Posted by: stevesliva Apr 2 2010, 08:34 PM

First I've heard of Spitzer Warm Mission results, a sort of Spitzer-does-Kepler:
http://news.discovery.com/space/spitzer-sheds-light-on-colony-of-baby-stars.html

Posted by: stevesliva Jan 9 2020, 02:47 AM

About 10.5 years, it turns out. (Am I allowed to quote to same question every other decade?)

Here's a countdown clock for the Jan 30th decommissioning:
http://www.spitzer.caltech.edu/final-voyage

6002 days in space.

Posted by: brellis Feb 2 2020, 04:44 PM

https://www.jpl.nasa.gov/news/news.php?feature=7588
Spitzer has been put into Safe Mode, mission declared complete. One assumes it will remain in its earth-trailing orbit indefinitely?

Posted by: stevesliva May 18 2023, 07:15 PM

I have seen a couple of headlines on this pass by in my various headline-serving algorithms:
https://arstechnica.com/space/2023/05/a-private-company-has-an-audacious-plan-to-rescue-nasas-last-great-observatory/

What I gather is that it will keep station with Spitzer, and just act as a communications relay. That seems especially dumb (?) ... seeing the headlines I was thinking it'd bring some liquid helium or something. Pretty limited ROI if it's just to communicate.

Posted by: nprev May 18 2023, 11:12 PM

Seems like a tech demo mission above all else, and that restoring comm with Spitzer by acting as a relay spacecraft to continue 'warm' operations would really just be a bonus. No attempt would be made to load He or anything else.

Posted by: marsbug May 19 2023, 10:48 PM

Actually I've been wondering about this: There articles my own algorithms have sent me have been light on details, but one quote that caught my eye:

From here: https://phys.org/news/2023-05-nasa-resurrect-spitzer-space-telescope.html

It definitely confirms it won't dock or load He, but "most complex robotic mission ever attempted by humanity" doesn't sound like it's just going to loiter and at as a relay....

Posted by: stevesliva May 20 2023, 03:35 AM

The other thing ... JWST is operational, and covers (without liquid He) the shorter wavelengths that "warm Spitzer" also covered. Again, more warm Spitzer seems even less indicated.

OTOH, Google seems to indicate cold Spitzer observed longer wavelengths than JWST, so getting cold Spitzer back after all these years would be a helluva thing.

Posted by: nprev May 20 2023, 06:10 AM

That 'most complex' quote is from a company representative, so there's obviously a bit of...er....poetic license being taken there.

The article also cites high demand for JWST time as a rationale, which makes perfect sense. There are a number of long-term but arguably lower-priority requirements from JWST's perspective that Spitzer could do instead, to say nothing of things like ongoing Solar System small body detection. Hope they do it.

Posted by: StargazeInWonder May 20 2023, 07:10 AM

I'll note here that the temperature in the permanently-shaded portions of lunar polar craters is about the same as Spitzer's operational cold temperature. For the purposes of long staring at deep fields off the ecliptic, a lunar polar observatory would seem like a good option, and wouldn't require any finite resources to maintain the temperature. Of course, a lot of the sky would be unobservable.

Posted by: siravan May 20 2023, 02:11 PM

Sending an IR telescope to the permanently shaded lunar south pole solves one problem but adds many other problems. Besides the whole issue with landing, one major concern is how to power it. By definition, solar panels won't work, and using RTGs negates the whole benefit of being in a cold region. Another issue is communication. You probably need relay satellites in polar or molniya-like (if this is even possible for the moon) orbits.

Posted by: nprev May 20 2023, 07:12 PM

Veering off topic here...let's not do that please.

Posted by: StargazeInWonder May 22 2023, 01:10 AM

On the note of JWST time, that's quite scarce, as a timely piece indicates here:

https://www.scientificamerican.com/article/jwst-will-hunt-for-dead-solar-systems-and-much-more-in-its-second-year-of-science/

Only 16% of Cycle 2 proposals were accepted, so if a revived Spitzer can make any observations that JWST is too busy for, that lightens the load. No doubt, many of the proposals cannot be satisfied with warm-mode Spitzer, but certainly warm Spitzer is still a valuable resource.

Posted by: marsbug May 24 2023, 08:39 AM

Definitely a possibility - though I wish they wouldn't: A mission across the inner solar system to (partially) restore Spitzer is impressive enough even if it is just a relay. At uni I took part in launching a weather balloon to 20 km, measuring the air pressure and sending a 'here I am' signal, and was plenty impressed: Clearly I am not the target audience of their PR!

Posted by: HSchirmer May 25 2023, 09:54 PM

That makes me kinda-wonder whether some sort of Webb-sunshade to create a cold-Spitzer extended mission might be future goal?