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Hubble Catches Some Cosmic Fireworks
Roland Piquepaille writes "On this Fourth of July, it's usual -- at least in the U.S. -- to watch fireworks. But I want to invite you to see very special ones, celestial fireworks discovered by the Hubble Space Telescope. Astronomy Magazine has the story. "In a newly released image, the Hubble Space Telescope peers into a neighboring galaxy to capture a gorgeous view of a supernova remnant called LMC N 49. Also known as DEM L 190, the nebula lies within the Large Magellanic Cloud approximately 160,000 light-years away." Read this summary for more details and a nice illustration from the Hubble Heritage Team. You can find additional tons of information at this Hubble Heritage Project page."
Check out this Hubble picture
Good thing they chose a non-technical name that would be easier to remember!
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They really shouldn't have tried to measure the mass of the Higgs boson.
That headline so not scientific it doesn't belong on Slashdot. Clearly the image is the face of the Virgin Mary. The virgin faces towards the southwest corner of the picture, her hands clasped in prayer. Try to be a little more rational with your descriptions next time.
As a betelgeusean, I would like to lodge a complaint.
Slashdot is becoming waaaaaay too Milky way-centric
here is another cosmic firework captured by hubble.
I was looking at this phenomenon earlier today and found out what actually causes these things.
Apparently somewhere in our Universe subatomic particles are being created with huge amounts of kinetic energy, these sparks are sent flying between galaxies at near light speeds, and these fireworks are what you see before they cool down and become invisible to telescopes.
There is no god
Is Slashdot were European, it'd shutdown in the afternoon and several times a month for a holiday. Heck, it'd be down most of the summer, too.
Unless there is a reasonable chance of losing appendages.
Everywhere else is a day of relief for today we confine the majority of our ordinance to within our own borders.
The APOD also has a good picture of this today.
well, hell, you don't ask for much do you?
I'll get right on that for you.
Sent from your iPad.
If you visit APOD (Astronomy Picture Of the Day) they link to a huge 7.2 megapixel version of this picture. So, unless your desktop is bigger than 2700x2700 anyone can scale it down and make a cool desktop from this.
No, the picture hasn't been "forged".
You're correct that the image was constructed from specific wavelengths with certain colours applied. Try going directly to the Hubble Heritage pages for this image. If you read the caption for the image you'll see:
The fast facts will tell you the exact filters used:
The numbers tell you the wavelengths in nanometres. They have possibly assigned red, green, and blue in the same wavelength order, in which case red=sulphur, green=H-alpha, and blue=oxygen.
If you really don't want to look at "cute pictures", don't look at the public outreach images. Take a closer look the original images.
Hope this helps.
This post is strictly my own opinion and not necessarily that of my employer.
click HERE for various resolutions of this image.
- The colour portion of the pic is a composite from two or more pictures.
- The colours are so vibrant you have to assume they're retouched
- the stars in the background were added
- many of the stars have lens flares
... Photoshopped in afterward
The meat of your complaint seems to be this: Do we have to win tax-payer support by drawing Star Trek scenes and releasing them to news outlets as "science"? And that's a very valid question, even if, as I pointed out above, nothing really fishy is being done here.True, but this is always true: in order not to saturate detectors, and to remove the inevitable cosmic rays, it is typical to take lots of dithered exposures. For an example of just how serious this cosmic ray problem is, take a look at this before and after image pair.
True, they are assigned, but it is very typical to get images in multiple filters, each of which has a well defined "color" - so it is easy to produce a final representative color image. Not even stretching the truth that much.
Well, they retained the stars from one image (so they were not added), and rendered that in greyscale. Artistic license, definitely.
Alas, flaring is typical: if you have bright stars in the field, the mirror obstructions (supports, secondary, etc) will produce flares. True at every optical telescope, from Palomar and Keck to the HST. Definitely not Photoshop!
My point of view, should that interest you, is this: except for a couple of very rare exceptions, every target the HST looks at is chosen after a brutal (trust me, brutal) review process. The HST costs an enormous of money to run, and they have lived up to that in terms of published peer-reviewed output per observation. So now if they kick in a few thousand extra bucks to take the science images, combine them with a little (not much, mind) artistic license, and release it to the public (who are, after all, paying for it) -- more power to them! Astronomy is one of those rare disciplines where the the excitement of cutting edge science can still be brought to the casual reader - if nothing else, as "Ooh, look, a pretty picture!" I think that is well worth it, as long as they aren't being scientifically dishonest.
(And that last point is a whole other story: do press releases over-hype the discovery? Does Nature twist a simple research result into "Unprecedented discovery revolutionizes our understanding of the Universe"? Maybe, but that's not a problem with the pretty pictures.)
"I will take the Ring," he said, "though I do not know the way."
I bet it's hard to find a professional astronomer who wouldn't produce false-color images. The reason multiple images have to be combined to get color information is that most astronomical detectors just count photons -- they don't sense color information. Astronomers doing imaging work get color info by taking exposures behind different filters and combining them with some sort of color map.
I'm sure the color table in this image was adjusted to bring out features, but real astronomers do this all the time (but they are more systematic about it...). Actually, many sources are very vibrant due to the fact that different molecules and ionization species emit at certain spectral lines. There are just huge clouds that are effectively neon lamps -- taking the energy from the supernova explosion and turning it into light at spectral lines.
Also, the "lens flares" you refer to are real. They are diffraction effects due to the support structure of the telescope. No real image of a star field would have points of light for stellar images.
Personally, I appreciate the PR efforts. Opportunities for the general public to get some sort of appreciation for science, whether it's just a pretty picture or not, is effectively raising the public awareness. Maybe the scientific value of this image is in inspiring the astronomers of the future.
People need to understand that HST isn't a big Canon digital camera. There is a lot of work involved in "reducing" astronomical data into a usable form, whether for science or PR. It makes no sense to use terms like "retouched." Raw data, as read out directly from the camera, is pretty much useless for any purpose. If I have an imaging run of a couple of nights at Palomar, for example, it generally takes at least two weeks (of long days) to get that data into a scientifically useful shape, at which point we use it to select objects for further spectroscopic study. After obtaining spectra, it takes more weeks to get the spectra into useful shape. Then we can start the long process of measuring scientifically useful things and learn something.
I think you're referring to the cross-shaped diffraction spikes around stars, not lens flares. These are real. They are caused by the diffraction of light from the stars by the cross-shaped secondary mirror supports.Don't worry about "destroying any scientific value." Telescope time is precious, whether on HST or any top observatory on the ground. You get diffraction spikes around bright objects (at least "bright" by the standards of the telescope). There's no way that the bright, spikey stars were the scientific target of that image. There's no way you would waste telescope time by exposing so long that your science object saturates or is surrounded by big diffraction spikes.