Slashdot Mirror
Looking For Intelligence
Calgacus writes "We've all read stories about extra-solar planets being found by gravitational wobbles. The Scotsman has a story here about a planet in the Fomalhaut system being discovered because of its wake through a dust cloud. It's further out than other recently discovered planets and astronomers are saying it means there's an odds-on chance of intelligent life being out there. If only there was more on Earth..."
i thought that space was absolute zero for temperature, or at least something remarkably close. how in the world are they able to get something colder on earth than they can in space?
You thought wrong. "Space" doesn't have a temperature in any very meaningful sense, but if it did it would be 3K, from the cosmic microwave background radiation. In the vicinity of a star, however, objects will reach a thermal equilibrium where the energy they absorb from solar radiation matches the infrared they radiate away. This is a lot higher in the neighbourhood of Earth orbit -- the Earth, for example, has reached a thermal equilibrium of around 285K (complicated slightly by extra heat produced by radioactive decay).
Ok. Now reread the article for what it actually says.
,who led the team,] said there was little chance of finding life on the planet because it was under constant bombardment from a surrounding belt of comets. "
"However, [Dr Holland
before that his unrelated comment to the finding was...
"Personally speaking, I think it must be odds-on that there is intelligent life elsewhere in the universe, and I think one day we will find it - or they will find us."
Please read the article all the way through before you jump to conclusions.
This space intentionally left blank.
This was also featured on space.com. Don't know if it's the same story since we seem to have slashdotted the Scotsman.
Got brain?
For those that don't know 3 K is not 3000 degrees whatever, its 3 Kelvin. 285 K is 285 Kelvin which is about 12C. 0 K is said to be absolute zero.
sig
One of the big disappointments of all the planets detected thus far is how closely they orbit their stars, making it quite unlikely that enough material was left when those systems were formed for smaller planets to form within the habitable zone of those systems.
If the big gasgiants are further away from the center of a solar system, then there is more chance that planets resembling Earth (or Mars, or Venus) will have formed.
With this discovery, it's become more likely that there is a significant amount of systems out there resembling our own solar system, and thus that we might some day discover the existance of recognizable life within those systems.
The answers to your questions are there in the article, really...it's just that the language the authors use is imprecise and hence confusing.
In simplest terms, Hubble can't "see" it because it's too dark. Optical telescopes just scoop up light in the visible spectrum; if the object you're interested in doesn't produce enough such light, then you won't see it.
SCUBA isn't looking for visible light, though; it's looking for electromagnetic radiation in a different area of the spectrum (different frequencies/wavelengths) than visible light. Since the object produces significant radiation at these frequencies, SCUBA can "see" it.
Regarding temperature: yes, it's cold where Hubble is (in the shade; it's very hot if you're in the sun), but that doesn't affect its ability to detect visible light. What matters is whether there's other visible light to interfere with the visible light it's interested in. In other words, if you're an optical telescope, you want it to be DARK around you...in an ideal world, the only source of light would be from the object you're trying to observe. Optical telescopes are looking for the difference between "absolutely dark" and "not quite absolutely dark". SCUBA, on the other hand, doesn't care about darkness, because it's not interested in visible light, but it does care very much about temperature, because at the wavelengths it deals with, heat energy affects its ability to "see", so it wants it to be COLD all around it; it's looking for the difference between "absolute zero" temperature and "not quite absolute zero".
It might help to: instead of "see", think "detect"; instead of "light", think "electromagnetic radiation"; and, consider temperature, wavelength, and frequency to all be ways of describing which part of the spectrum you're interested in.
Please donate your spare CPU cycles to help fight cancer and other diseases
They're cooling the detector of the telescope to reduce the dark current, in other words to reduce noise.
I suspect that the important difference between SCUBA and Hubble in this case is not the temperature of the detectors, but the method in which light is collected and what regions of the spectrum they choose to collect. The "A" in SCUBA stands for array - This means that SCUBA is actually a collection of telescopes spread out to form the equivalent of a very large telescope.
Also, many molecules in space are really "hot" - they have a lot of energy, but there aren't many of them around. Space is cold, however, it's possible for molecules to remain in highly energetic states for long periods of time. Temperature begins to become ill-defined.
.sig it up, fuckers!
That spin on it seems to have come from the newspaper. I work for one of the organisations involved, and you can see the original press release on our website.
This post is strictly my own opinion and not necessarily that of my employer.
I work for the organisation that operates SCUBA and the James Clerk Maxwell Telescope.
No - you're thinking of interferometer arrays. In this case SCUBA stands for Submillimetre Common-User Bolometer Array:
This post is strictly my own opinion and not necessarily that of my employer.
If you think the Drake equation is about "predict[ing] anything from a sample of 1", you don't understand it. The Drake equation lets us estimate the probability that we will run into intelligent life based on several other numbers that are easier to estimate well. That's the whole point: right now, we have only one world that we've explored thoroughly, so we want to figure out what else besides that sample of 1 we can use to predict things.
Low temperature physicists make things colder than this all the time - the same way that we can make things colder than the ambient temperature on Earth.
From memory, so might be wrong: In SCUBA's case, we use a vacuum jacket, then liquid nitrogen, then liquid helium, and then what's known as a dilution refrigerator (which I won't even pretend to understand!). It involves a mixture of liquid He3 and He4 I think. Gets us down to under 100mK.
Although experiments do go quite a bit colder, in terms of its size and the fact that it runs for extended periods at this temperature, SCUBA is one of the coldest fridges in the world.
(I work for the Joint Astronomy Centre who operate SCUBA and the James Clerk Maxwell Telescope.)
This post is strictly my own opinion and not necessarily that of my employer.
Not really, because 0K is not exactly -273C. It's something more like -273.15K. That number's from memory though...
This post is strictly my own opinion and not necessarily that of my employer.
Sorry that you think this is sensationalism, but this planet is sort of like what we've been looking for in the matters of even basic live existing in other locations of the universe. A large gas giant creating a debris-sink is exactly what jupiter and saturn do for our planet. They are the saftey net so to speak. Let me explain. There are thousands of roaming celestial bodies in our solar vicinity. Many of these are destined for the largest gravity well in the system, namely the sun. Well, there are planets in direct linear obstruction of these bodies and they usually just fall into the nearest gravity well they can find, usually eachother or another planet. The ONLY REASON that we haven't been wiped out is because most of these bodies tend to fall into jupiter or saturn and not reach little old earth at all. Without thos e two planets acting as graitivistic scape-goats, we'd be bombarded by every roaming rock in the heading toward Sol. (Excuse the hyperbole)
:)
What the scientists are stating is that if a planet, surrounded by debris far a way from the Folmahouth system exists, it will act as a buffer to those planets that we cannot detect. If it exists in two systems, Sol, and Folmahouth, then the "odds" are that it exists in many, (as you know, the universe is either infinite, or close enough to infinite, that only Marvin the Paranoid Android can count all the suns in it.)
So I don't think this is too sensationalist- for these reasons.
1. this wasn't printed on the front page of NYT
2. slashdot isn't much of a sensation
3. this is on the science section from the science department. If jerry springer was reporting on it, i'd buy the sensation part
4. Finding a gas giant *far_from* the sun with lots of debris around it means that there are likely smaller planets closer to the sun made up of heavy elements (like our planet) and life is likely to be present in many parts of the universe/galaxy.
http://cincyboys.blogspot.com/ Everything Cincinnati. Including the word 'Finnih'
of the Fomalhaut system and planet is today's Astronomy Picture of the Day.
Please this is not flamebait. The presented article was very bad and if Internet-based journalism is continued in such a way, there will be no more intelligence on this planet indeed.
What the article meant to say is that the existence of a huge planet in a far orbit from its star increases the probability of finding Earth-like planets in the habitable zone.
Life exists on this planet because it is protected by the big ones (Jupiter, Saturn) that attract comets and asteroids. So, scientists assume that a solar-like system will also have big planets orbing its outter rings.
The article is so bad that it says "other solar systems". There is only one solar system, and that is the one with the 'Sun' in it.
Maybe "planetary system" is a better term.
The fact that most of the detected planets are very close to their parent stars is no cause for concern. In fact, it's actually heartening that planets have been detected around only a few percent of the stars which have been searched.
Why? Because most of the current searches can only detect huge planets close in to their parent star. It's no surprise we've only detected planets of this sort... they're all we're capable of finding!
Don't worry about the close in planets. We've found a lot of them, but they aren't around most stars. The fact that they're there at all is what gives many of us the hope that planetary systems are commom!
A friendly neighborhood astrophysicist
The only reason most of the planets found (over 100 now) so far are very close to their stars is because of our observational bias. It's much easier to detect a massive planet that it close to the star since these cause the biggest "wobbles" from the star.
As planet hunting is in its relatively early days at the moment we are finding all the ones that are easiest to find, and looking at current stats they are now detecting planets out to 2 or 3 AU.
Also, because this has only been going on a few years we haven't been able to see the "wobbles" for planets that have orbital periods of more than a couple of years.
Basically, within the next few years we should start to find more stars with planets further out.
"There are bad people out there that will try to do bad things." - Microsoft 05/11/00
To put it country simple, if they could have gotten here, we'd be living on a reservation already.
So you're talking about Fermi's Paradox?
Fascism starts when the efficiency of the government becomes more important than the rights of the people.
I suppose some indiginous person from north/south america tried to say the same thing about visitors from another continent prior to the 1492. -"why would they come for gold, its not that useful a material" one of them probably said. Now take a step back and look at what the Europeans did to the America's.
Quick Summary
Foreign visitor from distant - seemed ok at first, ended up pillaging raping and destroying (and harvested minerals/natural resources). Why wouldn't something similar happen with space scenario? just cuz aliens have technology doesn't mean they won't destroy us with it.