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Planck Mission Releases Images of Galactic Dust

Soulskill posted more than 4 years ago | from the break-out-the-galactic-pledge dept.

Space 40

davecl writes "The Planck satellite has released its first new science images, showing the large scale filamentary structure of cold dust in our own galaxy. This release coincides with the completion of its first survey of the entire sky a couple of weeks ago. There's lots more work to be done, and more observations to be made, before results are ready on the Big Bang, but these images demonstrate Planck's performance and capability. More information is available on the Planck mission blog (which I maintain)."

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Size? (3, Insightful)

BradleyUffner (103496) | more than 4 years ago | (#31510554)

When talking about things at the galaxy scale, what is considered dust? Is this actual real "dust" of the size that collects on my shelves, grains of sand sized bits, gravel, or something larger?

Re:Size? (4, Informative)

vlm (69642) | more than 4 years ago | (#31510898)

When talking about things at the galaxy scale, what is considered dust? Is this actual real "dust" of the size that collects on my shelves, grains of sand sized bits, gravel, or something larger?

The phrase to google for is "cosmic dust"

You'll be displeased with the answer, it seems to be a very wide range of stuff from two molecules having a public display of affection all the way up to the low end of vaguely sand-like.

I don't really know what collects on your shelves, but "cosmic dust" is probably vaguely similar.

This sand and gravel stuff you talk about, is by definition a "meteor".

http://en.wikipedia.org/wiki/Cosmic_dust [wikipedia.org]

http://en.wikipedia.org/wiki/Meteor [wikipedia.org]

Re:Size? (2, Informative)

Impy the Impiuos Imp (442658) | more than 4 years ago | (#31516104)

It's also pretty thinned out, often where it takes light years' worth of a "cloud" of it to finally provide enough coverage to 100% block out the stars behind it.

Re:Size? (3, Informative)

Bemopolis (698691) | more than 4 years ago | (#31511228)

Since a lot of the dust in a residential home is composed of skin cells, then no, not so much:). In general, interstellar dust is composed of carbon and silicate grains, with sizes on the order of 100 nanometers. Think less "dust" and more "fine soot".

Re:Size? (1)

nschubach (922175) | more than 4 years ago | (#31511238)

So, umm... with all that dust out there, is it possible that light could be attenuating between here and the perceived "edge" of the universe? Couldn't the presence of large amounts of dust mean that our universe is larger than current estimates?

Think of it like your headlights on a dark night... the further away you get the more light disperses. Since there's less stuff in space to disperse light, we can see for X billion light years, but the presence of dust could be masking a large portion of visible space in this manner. I would assume this would have to happen, otherwise space would be white with light instead of black, right?

Re:Size? (3, Informative)

Colonel Korn (1258968) | more than 4 years ago | (#31511452)

So, umm... with all that dust out there, is it possible that light could be attenuating between here and the perceived "edge" of the universe? Couldn't the presence of large amounts of dust mean that our universe is larger than current estimates?

Think of it like your headlights on a dark night... the further away you get the more light disperses. Since there's less stuff in space to disperse light, we can see for X billion light years, but the presence of dust could be masking a large portion of visible space in this manner. I would assume this would have to happen, otherwise space would be white with light instead of black, right?

It's well known that there's a lot of dust, that doesn't hurt our understanding of the size of the observable universe. It might increase our error bars a little in the first few steps of the distance ladder (http://en.wikipedia.org/wiki/Distance_ladder), but probably not significantly. Dust isn't an effective absorber of every wavelength of light, so we can see through it if we want.

If you really want to get a good handle on this rather complex and fascinating topic, read the above article and the less awesome but still useful article on the size of the observable universe (http://en.wikipedia.org/wiki/Size_of_the_universe).

Re:Size? (2, Informative)

Anonymous Coward | more than 4 years ago | (#31512024)

"Couldn't the presence of large amounts of dust mean that our universe is larger than current estimates?"

No, because current measurement of the size of the observable universe is not based on brightness but is based on redshift.

Re:Size? (0)

vlm (69642) | more than 4 years ago | (#31513534)

No, because current measurement of the size of the observable universe is not based on brightness but is based on redshift.

Which brings us right on back, circularly, to "Couldn't the presence of large amounts of dust mean that our universe is larger than current estimates?"

I'm just saying, dust probably comes along with a free order of hydrogen gas clouds, the spectrum of which might be redshifted at a velocity that has nothing to do with the galaxies/stars behind them.

My wild guess, to work around that problem, would be to watch redshift and light curve of supernovas in distant galaxies...

Re:Size? (1)

Doctor Morbius (1183601) | more than 4 years ago | (#31514914)

Don't you think that cosmologists have thought of this already? Trust me they have. That's why they're cosmologists. The last thing a cosmologist wants to do is make a claim based on sloppy work only to be proven wrong later.

Re:Size? (1)

lgw (121541) | more than 4 years ago | (#31515166)

It ... doesn't work that way. If you care about this subject (and it seems like you do), you might find it entertaining to read up on at least the very basics [wikipedia.org] , as might be found in Wikipedia.

Re:Size? (4, Informative)

c++0xFF (1758032) | more than 4 years ago | (#31511368)

APOD has a good description and picture (well, computer-generated visualization) of dust:

By studying how dust absorbs, emits, and reflects light, astronomers do know that interstellar dust is much different than the cell and lint based dust found around a typical house. Interstellar dust grains are composed mostly of carbon, silicon, and oxygen and are usually less than about 1/1000 of a millimeter across. Recent work indicates that most dust grains are not spherical. The above picture shows the result of a fractal adhesion model for dust grains involving random conglomerates of spherical compounds of different properties, here artificially highlighted by different colors.

(from http://apod.nasa.gov/apod/ap961119.html [nasa.gov] )

Re:Size? (1)

Hoi Polloi (522990) | more than 4 years ago | (#31512610)

Whatever it is one thing is for certain, the galaxy is filthy. No wonder I'm always sneezing.

That's no dust cloud (2, Funny)

Rik Sweeney (471717) | more than 4 years ago | (#31510578)

Best call the Fantastic Four, it sounds like we're about to receive a visit from the Silver Surfer [wikipedia.org]

High-Res? (1, Interesting)

ircmaxell (1117387) | more than 4 years ago | (#31510604)

They consider 1000x892 pixels high resolution? Last I checked, that was high res circa 1995... I'd LOVE to see some of those shots at something at least large enough that my monitor could display naively (2500x1600 minimum), yet alone being able to zoom in...

Re:High-Res? (3, Informative)

vlm (69642) | more than 4 years ago | (#31511276)

They consider 1000x892 pixels high resolution? Last I checked, that was high res circa 1995..

For marketing / PR / Journalist folks that is high-enough res... it'll look OK on a HDTV, a web page, or in a 100 dpi B/W newspaper. They call it a "press" release for a reason, not a science release or a data release.

If you want 2000x1500 or whatever, I think you're asking for the science data, which is not released yet. Usually the way it works with space probes is the folks whom ran it keep the data to themselves for "awhile" before its released to the public. Usually "about a year". No idea how it works with Planck, couldn't even google it.

Since the public doesn't really care (just being honest here) I think the main purpose of early press releases is to intimidate the researchers whom aren't in the inner circle whom have actual data.

I did find a nice description of the HFI "imager" device... Its resolution is about 5 arc minutes depending on frequency, etc.

Your eyes resolution is about 1 arc minute. So, the output of the HFI would be a slightly blurry version of what your eyes see, sort of. Just drink a few beers and drop some acid and look at the stars and you'll be pretty much on your way.

I did not bother researching the other instruments on Planck. Someone with more motivation can do that and gain the karma.

http://xxx.lanl.gov/ftp/astro-ph/papers/0308/0308075.pdf [lanl.gov]

http://en.wikipedia.org/wiki/Visual_acuity [wikipedia.org]

Re:High-Res? (1, Funny)

Anonymous Coward | more than 4 years ago | (#31515176)

Ooock Imm don, shtooned like heeeeell! And I see shchmurfs jumpinn outta my windowss, cuz i took the acid too, ya now? But, can't find the shtars you talkin' about. Schmurf says its 3 pmm, i flucked something up?

Re:High-Res? (2, Funny)

Chris Burke (6130) | more than 4 years ago | (#31516158)

I did find a nice description of the HFI "imager" device... Its resolution is about 5 arc minutes depending on frequency, etc.

Not bad for the smallest telescope possible!

Huge waste of money (3, Insightful)

Locke2005 (849178) | more than 4 years ago | (#31510644)

If they wanted pictures of dust, they could have just photographed under my bed!

Re:Huge waste of money (1)

geekoid (135745) | more than 4 years ago | (#31511166)

They said dust, not life forms.

Re:Huge waste of money (1, Funny)

Anonymous Coward | more than 4 years ago | (#31513238)

...not life forms.

Specifically, gametes.

Yeah, no. No one is looking for that.

Re:Huge waste of money (1)

Locke2005 (849178) | more than 4 years ago | (#31513920)

Those are on the sheets, not under the bed!

Re:Huge waste of money (1)

Impy the Impiuos Imp (442658) | more than 4 years ago | (#31516188)

And back to dust, full circle!

> (Score:2, Troll)
>
> If they wanted pictures of dust, they could have just photographed under my bed!

Troll? If a particularly Angela-esque person wanted to slam a humor post, go ahead, but at least use "off topic".

Unless...unless it hit too close to home? But then the nerds/sex issue should really send this person into a tizzy.

Where is Mega Maid? (1)

Voyager529 (1363959) | more than 4 years ago | (#31510988)

I mean, you'd think the break-out-galactic-pledge department would have her on speed dial or something.

Re:Where is Mega Maid? (2, Funny)

Impy the Impiuos Imp (442658) | more than 4 years ago | (#31516216)

They do -- that's prolly why she stopped returning calls.

A nice picture (0, Redundant)

geekoid (135745) | more than 4 years ago | (#31511150)

Nice try (3, Informative)

Locke2005 (849178) | more than 4 years ago | (#31511290)

Planck [startswithabang.com]

Re:Nice try (1)

IceFoot (256699) | more than 4 years ago | (#31512280)

Nice picture. Oh,look! It's held together with masking tape!

Re:Nice try (1)

Locke2005 (849178) | more than 4 years ago | (#31512608)

That's duct tape, you fool! Red Green would be proud!

Re:A nice picture (3, Funny)

Lumpy (12016) | more than 4 years ago | (#31511528)

Wow! It looks just like the hosted by tripod logo!

Fractals! (2, Interesting)

hlee (518174) | more than 4 years ago | (#31511444)

FTA: One puzzle to be solved is why there is similar filamentary structure on both the large and the small scale. "That's a big question," says Tauber.

Interesting that these filaments could probably be modeled using fractals. http://en.wikipedia.org/wiki/Fractal [wikipedia.org]

Constant Value For Dust (2, Funny)

MrTripps (1306469) | more than 4 years ago | (#31511636)

Since dust is so difficult to define, maybe they should set a standard for what is and is not dust. Since it came up from this mission they could call it the Plank constant. That isn't used for anything else is it?

Looks like Vernor Vinge's "Zones" (3, Interesting)

wisebabo (638845) | more than 4 years ago | (#31511714)

In Vernor Vinge's fantastic book "A Fire Upon The Deep", he postulates the existence of "Zones" where variations in cosmic constants(?) allow increasingly sophisticated intelligences (and corresponding FTL travel). We (earth) live in the "Slow Zone" where only human level intelligence is possible.

Anyway these pictures, with their galactic scale structures showing Fractal like properties, reminds me of that!

By the way, the book really is awesome (Hugo and Nebula winner) just about the best SF I've read along with Stanislaw Lem's "Imaginary Magnitude". If you're a slashdot geek (and aren't we all?) you'll love his galactic Internet (he's a computer science professor). Oh, and he is credited with the idea of the "Singularity".

Re:Looks like Vernor Vinge's "Zones" (1)

radarsat1 (786772) | more than 4 years ago | (#31513504)

I always found that zones thing such a weird aspect of that book. On the one hand I found it so strange and, really, unscientific, that I didn't know whether to consider it stupid or silly. On the other hand I thought it made a really, really cool plot device. That was enough to make me want to read more books featuring this idea, but I don't know if he ever wrote any?

Btw, I thought Kurtzweil was credited with the Singularity?

Re:Looks like Vernor Vinge's "Zones" (1)

Kwitset (1557153) | more than 4 years ago | (#31516124)

That was enough to make me want to read more books featuring this idea, but I don't know if he ever wrote any?

"A Deepness in the Sky" is set in the same universe, but if I remember correctly the whole books takes place in the slow zone.

Re:Looks like Vernor Vinge's "Zones" (1)

Impy the Impiuos Imp (442658) | more than 4 years ago | (#31516256)

Vinge has admitted it was a way to basically get around what he sees as inevitable -- the coming of the Singularity, and probably well before there is any interstellar, much less intergalactic, travel.

Hence he has no real way to write stories set in classic sci-fi space, with alien races and rockets and FTL ships and what-not. It will never be that way.

Zones was a way to get around what he sees as (and I agree with) an inevitable end stage for humanity, and not really too far in the future.

Anybody? No? Dust. (1)

heidaro (1392977) | more than 4 years ago | (#31512176)

I wonder if this dust is high in fat.

Book Scanning (1, Interesting)

Anonymous Coward | more than 4 years ago | (#31515028)

This looks like someone simply scanned the cover from a 1970's science fiction paperback. It's beautiful on many levels.

Re:Book Scanning (1)

Impy the Impiuos Imp (442658) | more than 4 years ago | (#31516286)

Too bad it doesn't look like the cover of some bad '70s erotica pulp fiction. "Women's Prison", et al.

Breakdown (1)

Voyager529 (1363959) | more than 4 years ago | (#31527600)

Disclaimer: This is from my personal, anecdotal experience. YMWV...

-Microsoft Security Essentials is the current weapon of choice for people too stingy to pay for protection. It does a good job though, and like has been reiterated many times over, it's pretty light on system resources, it doesn't nag unless you have a virus (though it will give you a "yellow signal" if your Windows Update patches aren't current), and it's straightforward in the event the end user actually has to do anything in it.

-Avast is my second choice. In my experience, Avast (at least the 4.8 version) is the only antivirus I know of that has a custom installer that will function properly in safe mode. In the event that the system is already hosed, if you can get into safe mode, you'll probably be able to install Avast (along with their definition updates that also come as a standalone installer if Safe Mode w/Networking doesn't work) and do a boot-time scan to get you back up and running. I haven't played much with version 5, but both 4.8 and 5 seem to have their pros and cons - 4.8 is lighter, but 5 gives a more polished user experience. If you go for this one, try each version. The first-party Avast site offers both for now, but filehippo.com has an archive of older versions if Avast decides to only offer 5 at some point in the near future and remove the 4.8 link.

-Avira is handy to have, and is shipped on the Ultimate Boot CD for Windows (www.ubcd4win.com). In that context it works really well, but IMO an antivirus shouldn't be naggy, because then users start to become conditioned to ignore it, and that's something that will NEVER be desirable. As a repair scanner on the UBCD where you can run your scan and reboot, great. There's no reason to have your family get nagged by the virus scanner.

-AVG is almost the de facto standard in freeware antivirus apps; it's the rare week that it's *not* #1 on the download.com download list (ironically enough, Limewire tends to be #2). I used to think it was alright, and did use it for a while, but it started to get a bit "heavy" on the install side, a bit naggy with the "special upgrade offers", and started slipping on the detection/removal rates.

While this is about freeware antiviruses, there's a few noteworthy for-pay applications that I feel are at least worth taking a look at:

-NOD32 is tiny (v.2.7 was written in assembler and has a 12MB installer; even the x64 version is only 35MB). It's fast. Virtually every review I've read has had its detection rates among the highest available. In my experience, that holds extremely true; not one of my friends and/or family who have coughed up for NOD32 have ended up infected without hitting the 'ignore' button. For $40/year (10% discount for typing "LEO22" at checkout; 2-year and multilicense discounts as well), it is really protection worth paying for. Also, v.4.0 includes a widget to burn a bootable CD that will update itself and scan for viruses on the host machine without booting into Windows. That's a really handy feature. If you're really cramped on system resources, the 2.7 version is also available from FileHippo and will be supported through 2012. Amazingly enough, it will install on anything from Windows 95 to Windows 7 x64.

-Acronis just released a security suite called Backup&Security in conjunction with BitDefender. It's not as light as NOD32 (in fact, it's among the heavier apps available and thus not for the faint of RAM), but I've never seen a more full-featured antivirus. Antivirus, Antispam, firewall, parental controls, IM protection, game mode, all the features of Acronis True Image Home for scheduled backups and disk imaging, centralized management across the home LAN, 5GB of online backup, and three licenses for $70. If there are multiple machines in the same household that need to be secured and have enough RAM to handle it, it's seriously worth a look.

Also, as far as on-demand scanning goes, the freeware Combofix app is sheer amazingness. It's not a comprehensive virus/malware scanner, but it is ruthlessly effective at getting rid of the stuff that most users would visibly notice. It's also pretty effective at removing infections that hijack DNS records and do other things to prevent its removal. New versions are released frequently, but it's 3.8MB footprint is a staple on my USB flash drive.

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