Starship Asterisk*

The colors in this image indicate temperatures in the dust that permeates the Cloud. Colder regions show where star formation is at its earliest stages or is shut off, while warm expanses point to new stars heating surrounding dust. The coolest areas and objects appear in red, corresponding to infrared light taken up by Herschel's Spectral and Photometric Imaging Receiver at 250 microns, or millionths of a meter. Herschel's Photodetector Array Camera and Spectrometer fills out the mid-temperature bands, shown here in green, at 100 and 160 microns. The warmest spots appear in blue, courtesy of 24- and 70-micron data from Spitzer.

Bionic wrote:It is unfortunate that the Herschel Space Telescope is a use-and-throw-away facility. Recycling of hardware and precious materials is as much a part of scientific study as it is of daily townsfolk routine. The abandonment of scientific instruments after use is absolutely abhorable and summons an ancient theme concering the environment --> use only that which you can recycle.

Chris Peterson wrote:

Bionic wrote:
It is unfortunate that the Herschel Space Telescope is a use-and-throw-away facility. Recycling of hardware and precious materials is as much a part of scientific study as it is of daily townsfolk routine. The abandonment of scientific instruments after use is absolutely abhorable and summons an ancient theme concering the environment --> use only that which you can recycle.

Recycling makes little sense when the cost of that recycling exceeds the cost of using new materials by several orders of magnitude. We have only to look at the HST, which was designed to be repaired. That poor decision reduced the utility of the telescope by requiring it to be in a less than ideal orbit, as well as by sucking up in repair costs the money that could have been used to build two or three additional telescopes.

The cost that would have been incurred in making the Herschel Observatory repairable, recyclable, or extendable would have prevented the mission from ever being launched in the first place.

http://en.wikipedia.org/wiki/Herschel_Space_Observatory wrote:
<<The Herschel Space Observatory is a European Space Agency space observatory sensitive to the far infrared and submillimetre wavebands (55-672 µm). It is the largest infrared space telescope ever launched, carrying a single mirror of 3.5 metres in diameter. Herschel is in its final months, it is hoped its coolant will last until March 2013. The observatory was carried into orbit in May 2009, reaching the second Lagrangian point (L2) of the Earth-Sun system, 1,500,000 kilometres from the Earth, about two months later. Herschel is named after Sir William Herschel, the discoverer of the infrared spectrum and planet Uranus, and his sister and collaborator Caroline Herschel.

The Herschel Observatory is capable of seeing the coldest and dustiest objects in space; for example, cool cocoons where stars form and dusty galaxies just starting to bulk up with new stars. The observatory will sift through star-forming clouds—the "slow cookers" of star ingredients—to trace the path by which potentially life-forming molecules, such as water, form. The United States through NASA is participating in the ESA-built and -operated observatory. It is the fourth 'cornerstone' mission in the ESA science program, along with Rosetta, Planck, and the Gaia mission.

The mission involves the first space observatory to cover the full far infrared and submillimetre waveband. At 3.5 meters wide, its telescope incorporates the largest mirror (made not from glass but from sintered silicon carbide) ever deployed in space. The mirror was ground and polished by Opteon Ltd. in Tuorla Observatory, Finland. The light is focused onto three instruments with detectors kept at temperatures below 2 K (−271 °C). The instruments are cooled with liquid helium, boiling away in a near vacuum at a temperature of approximately 1.4 K (−272 °C). The 2,000-litre supply of helium on board the spacecraft will limit its operational lifetime; nonetheless, it is expected to be operational for at least 3 years.>>

Ann wrote:Boomer12k, I never look at astroimages that way! But I like it. I can barely spot your Anime Cat Lady Pirate, but I think I can really see a cat at nine o'clock in this image. Its head is outstretched to the left and held sideways. We can see its eyes and some white above its eyes, and I think I can spot its ears, too. And at about five o'clock I can see a big, dark wolf. I can see its open jaws, two large, misshapen ears, and one, perhaps two, glowing white eyes!

What I really see when I look at a picture like this, however, is how round the Large Magellanic Cloud really is. In visual light, it is so easy to focus on the prominent bar of the LMC and of course on the magnificent Tarantula Nebula. Spiral and irregular galaxies easily look like bright non-spherical structures with a lot of emptiness between the bright parts:

But the empty parts are not empty, just not very luminous. Today's APOD brings out all the non-luminous dust that permeates the large conglomerate of dark and baryonic matter that is the Large Magellanic Cloud. The bright and brilliant stars and nebulae are really just like foam on a large, deep sea.

One thing we can't see in today's APOD is the prominent bar of the LMC. Galactic bars are typically made up of old or at least intermediate stars, and there is usually little dust in the bar. A typical feature of barred galaxies, however, is an enhanced rate of star formation at or near the ends of the bar. The incredible star cluster R136 and the fantastic Tarantula Nebula are perfect examples of enhanced star formation near one end of a galactic bar, and the Tarantula Nebula region does indeed show up well in the infrared picture. Gas and dust are being funneled to the end of the bar, where it accumulates, leading to enhanced star formation. This dust shows up well in infrared images. But the star formation in itself also creates dust, making regions of star formation very dusty and easy to spot in infrared images.

Ann

To identify the location of the supernova and navigate your way around the many star clusters and nebulae of the LMC, just consult this well-labeled view.

Last edited by bystander on Sat Mar 23, 2013 8:11 pm, edited 2 times in total.
Reason: please, no hot links to images > 400kb (file size)

davidlfoster wrote:
OK, which is it? This APOD edition says the LMC is 30,000 light years across and the edition referenced for the optical image says it is 15,000 light years across. Those numbers are pretty different.

http://apod.nasa.gov/apod/ap100903.html wrote:
The Small Magellanic Cloud actually spans 15,000 light-years or so and contains several hundred million stars.

http://apod.nasa.gov/apod/ap081219.html wrote:
Spanning about 30,000 light-years or so, [the Large Magellanic Cloud (LMC)] is the most massive of the Milky Way's satellite galaxies and is the site of the closest supernova in modern times, SN 1987A.

MargaritaMc wrote:Is there a way of finding out the size of a file for potential hot-linking? I know that if I download an image I can discover the size that way - but is there another way?

davidsaroff wrote:What is the filamentary and web like structure due to? I've heard "shocks" and "magnetic fields" but it looks like neither.