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Astronomers Find Sun's Twin
mroch writes "Space.com is reporting that astronomers may have found a solar twin -- a star almost exactly like our own Sun. Interesting tidbits from the article include: "The star, 18 Scorpii, sits about 47.5 light-years away in the constellation Scorpio, and has long-been suspected of being Sun-like. [...] The star burns slightly hotter than the Sun, at 5,789 degrees Kelvin compared to 5,777 degrees. It appears to rotate slightly faster than the Sun, taking 23 days to complete a rotation rather than the Sun's 25." It boggles my mind to think that we can measure temperature that exactly from 279,000,000,000,000 miles away, and that they are complaining over a 12-degree difference."
Distance actually does not matter with respect to the method used to measure the temperature, as long as you have enough light, and there is no disturbing medium in between. Both conditions seems to be met.
They can determine the temperature by the wavelengths of light given off by the star.
And those dozen degrees are in Kelvin. These aren't your ordinary units of measurement we're talking about.
I have been pwned because my
IIRC, the temperature is measured by the colour of the sun. That doesn't change the further away you get, so its just as accurate over long distances as short. However, there is the problem of dopler shift if the stars are moving away/toward each other.
"When I grow up, I want to be a weirdo"
What do we know about that star and its surroundings? Is it likely to have inhabitable planets or is it bathed by lethal radiation from neighboring novas?
How long before we can actually check these stars for Earth-like planets? Last I heard, we now had the ability to detect planets slightly smaller than Jupiter. Will we find, or even see, an inhabitable planet within a few decades?
"Fascism:Extreme right-wing dictatorial government,belligerently nationalist,that merges state and business leadership"
To make it more accurate, scratch "right-wing". This opens it up to the majority of fascist governments, which have in fact been left-wing. You have also left out the part about "stringent socioeconomic controls", which is another hallmark of left-wing fascist governments (with their higher taxes, and takeover of such economic sectors as health care where government has no business meddling).
nt
From the National Academies Press
"LORD KELVIN. Honored for his contributions to science and to the British realm, hailed as a genius, courted for his charm and wit, feared for his sharp tongue and intimidating manner - and ultimately ridiculed by his peers who labeled him a dabbler, a pretender of the worst sort. "
"Charismatic, confident, and boyishly handsome, Thomson was elevated to the peerage by the Queen for his achievements. Indeed, his name survives in the designation of degrees Kelvin, the temperature scale on which absolute zero is defined. Lauded for his brilliance, Sir William Thomson, Lord Kelvin, was Great Britain's unrivaled scientific hero."
[C:\>net send all This is a joke!]
:-)
So where's the news? It was already predicted somewhere else. Also, they predicted the failure of the Beagle...
Nothing to see here move along...
My Stack Overflow user
"... and that they are complaining over a 12-degree difference."
Who's complaining?
Observation != complaint.
for my 2 pence, this twin bit is just bunkum
They are 0.3 billion years different in age (presumably USian billions)
Which is almost 10% of their total age, that's like your human twin being born when you are 8 years old but you both weigh the same!
It is a bad analogy.
There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
seeing as they are currently 50% through their expected lifespan
There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
Does this have to be off-topic? How about that planet in Star Trek that was just like Earth, but it was run by Nazis.
god damn these robotic eyes
There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
I like David Nash's list of 50 nearby sunlike stars within 50 light years.
18 Scorpii is on there, as is the infamous Tau Ceti. 18 Scorpii was one of the four closest matches.
Binary geeks can count to 1,023 on their fingers
They determine the temperature of a star, based on the light it gives off? That is bogus. What if something in between the star and Earth is changing the wavelength of the light? I can shine a light-bulb through a green sheet of plastic, and change it, but the temperature of the bulb doesn't change.
does anyone here know what advances would be necessary to send probes & recover data about nearby star systems? Ion drives seem to be moving in the right direction, to use a phrase, but would they be sufficient in longevity & speed to make a multi-light year journey? And what sort of remote communication would be possible at such distances?
A corollory to this is, does anyone know what (if any) systems the Voyager spacecraft are going to encounter, and when?
>(presumably USian billions)
US and UK billions are now both 1,000,000,000. The UK changed some time ago in order to make financial reports and transactions across the atlantic a lot less ambiguous.
"When I grow up, I want to be a weirdo"
Actually, that distance would be more like 2.7862056^14 miles.
186,000 miles/second x 60 seconds/minute x 60 minutes/hour x 24 hours/day x 365 days/year x 47.5 years.
There are no stupid questions, only stupid people asking questions.
You know, these arbitrary names come after greek words. They used these words to refer to small things, so scientists, centuries after them, use these words to refer to powers of ten.
If you are measuring in inches, you have to memorize arbitrary numbers, because there are 5280 inches in one mile, and 12 inches in a feet, which makes calculations cumbersome and prone to error.
Metric system is intuitive, because every unit is a power of ten of a meter. This is the only thing arbitrary.
Face it. Metric system r00lZ! Any other system sucks!!
If we send a probe now, in the next X years we'll be able to send a better probe. It will go faster and arrive sooner than the first one.
isn't very likely to go at c. 0.0001c is more realistic :)
"Left-wing" and "right-wing" are relative terms. The "right wing" is the Establishment and the "left wing" is the anti-Establishment. Therefore in a conventional Western democracy, "right wing" refers to capitalism (and liberalism?) where that is the Establishment, and "left wing" refers to radical alternatives like Communism, Anarchism etc. In SOVIET RUSSIA, by contrast, the Establishment was the Communist Party, and therefore the "right wing" in that particular country. This is completely off-topic but it's something I've been dying to shout about in public for years.
Stick Men
In fact, nano is Italian and means dwarf.
And if you go a bit further:
femto and atto are Danish (I guess) and mean fifteen and eighteen (digits). Easy, isn't it?
Say out loud: I'm an Aspie and I'm somewhat proud, I guess. Uh. Can I write an email in all caps instead? Hm...
No.
"Left" and "right" have their origins in the seating arrangements of a pre-Revolution French parliament. Nobles sat on the right, commoners (or rather, their representatives, who weren't quite so common) sat on the left. Thus, generally, being on the right was to support the privileged class; being on the left was to support the common people and more equality.
In their modern forms, the right supports (and usually hopes to join) the "privileged nobles" of the capitialist class, those to whom the state has granted control of the means of production; the left seeks a more equitable arrangement, supporting the rights and interests of the "common" laborers.
Properly, "right" and "left" refer to economic arrangements. Using them to talk about the orthogonal political dimensions of legislated morality and foreign policy results in great confusion.
Tom Swiss | the infamous tms | my blog
You cannot wash away blood with blood
There you go. That's why I spend quite a bit of time and mod points pointing out to idiots that when they trash the "damn liberals" they don't know what they are talking about. The Republican party in the US sure loves to conflate every boogeyman in the book.
Liberal and proud.
This is America, damnit. Speak Spanish!
What do we know about that star and its surroundings? Is it likely to have inhabitable planets...
As cool as it is to find a star that's a twin to ours, it's incredibly unlikely that we'll find a planet even remotely similar to Earth.
For one thing, the article notes that 18 Sco is 4.2 billion years old, while Sol is 4.5 billion years old. If everything else were exactly equal, it would be like stepping back 300 million years back in time. A quick Google finds that one of the more complex forms of life found 300e6 years ago on this planet was the Velvet Worm -- not a species known for its technology.
But even that is unlikely, given the Earth's unusual formation. This planet has an unusual mix of minerals on its crust, plus plate tectonics to keep them mixed, and an iron core that's magnetic enough to keep out the sun's ionizing radiation. Plus, a moon big enough to stir up the oceans, and a tilt to generate asymmetrical solar heating... and all that apparently due to a one-in-a-million collision between a proto-Earth and a Mars-sized planet not long after Sol formed.
I can't find the quote, but someone calculated the odds of finding another sentient species as tiny. It's not that it doesn't develop elsewhere in the galaxy... there are billions of chances, so surely more than one came up all 7s. It's just that the distances are so vast, and the chances of favorable development so small, that entire civilizations (or species) could rise and fall by the time their transmissions reach another civilization's satellite dishes.
But still, at less than 50 light years, it would only take a few hundred years to get there and back. Are the generation ships ready yet?
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
12in = 1ft
3ft = 1 yd
1760yd = 1 mi
63360in = 1 mi
Sometimes I long for the good old days of the dram and the cubit...
"Murphy was an optimist" - O'Toole's commentary on Murphy's Law
Now scientists just need to solve that little problem of us not being able to travel one light year yet, let alone 47 and we're good to go.
It boggles my mind to think that we can measure temperature that exactly from 279,000,000,000,000 miles away, and that they are complaining over a 12-degree difference."
Considering the fact that they used the same method to measure the temp of this new sun as they probably used to measure the tmep of our existing sun which is also considerably far away (albeit it closer to us) I'd say the measurements are just as accurate as they could be.
That's almost as amazing as finding one's "hand twin!" I know I'd pay good money to see twin stars showcased in some type of entertainment venue. Gosh.
"This is completely off-topic but it's something I've been dying to shout about in public for years."
You've had your chance to announce to the world that you're an ignorant fool.
Congratulations.
Welcome to my pile of -1s, you'll be in good company.
YAW
Your head of state is a corrupt weasel, I hope you're happy.
Better catch this before someone else jumps on it -- IRRC should be IIRC.
I apologize for any computer crashes, wars, or deaths this may have caused.
- Hail to our fearless misleader! Fool speed ahead!
Don't we also affect spin by moving mass around on the earth? Building large buildings slightly slow the spin, while filling in sea level areas with fill-dirt from higher regions would counter-it. Of course, all of this should be an extremely small effect, right?
www.facebook.com/DareDefendOurRights
www.fairtax.org
I think it's going to turn out that what we call our sun is actually the twin, and that other star is the real sun.
Yipee! Once again slashdot fulfils it's purpose: an anonymous ranting ground for the frustrated and not necessarily well informed :-)
Stick Men
...and that they are complaining over a 12-degree difference.
Umm.. we are talking about kelvin here. It's not like they're measuring in F or C. That would truely be impressive.
I'm against picketing, but I don't know how to show it.
It boggles my mind to think that there are people so damn anal about spelling and grammar they would waste breath to critic a perfectly readable post that has a perfectly clear meaning.
It's not as if it MATTERS if the meaning is clear.
critique ?
5280 ft = 1 mi
bad spelling troll, begone.
Are the babes on twin earth proportionally hotter to?;-)sorry, its all i got... yeah, i know...*gets up and leaves*
"Sic Semper Tyrannosaurus Rex."
It's already been found. Earth's twin is on the exact opposite side of the sun from Earth. That's why it has never been observed. It is inhabited by aliens who dress like japanese businessmen and Gamera sometimes flys there to rescue children kidnapped by flying saucers before their brains can be eaten. Get with the program.
Liberals call everyone Nazis yet they are the closest thing to it.
You forgot to capitalise the first letter of the sentence...
Mary-Kate or Ashley?
So it's less like the difference between a warm day and a cool day, and more like the difference between a warm day and a cold day.
Those who sacrifice security to condemn liberty deserve to repeat history or something. - Benjamin Santayana
and i have trouble getting accuracy to within .01 from a distance of 3 meters, in the shop...
they're certain that they are accurate to within better than 0.5%, from that distance, hunh?
Okay, people keep repeating the "Kelvin degrees are different from Celsius or Farenheit" thing. Okay, a 12 degree difference in Celsius is exactly the same as a 12 degree difference in Kelvin.
K = degrees C + 273
So that -273 degrees C is equal to 0 kelvin.
What I don't understand is why they are using Kelvin anyway. Kelvin is usually used for extremely cold stuff, not extremely hot stuff. The point of Kelvin was to be able to deal with temperatures as cold as absolute zero (( 0 kelvin )) without negative or complicated numbers.
Maybe they want the heat to seem more impressive?
Or perhaps they like to make silly slashdotters think kelvin is extremely different....
My comment was meant as a joke.
Since it wasn't moderated that way, I can only assume that nobody on the planet except for me has a sense of humor.
Those who sacrifice security to condemn liberty deserve to repeat history or something. - Benjamin Santayana
Sorry, didn't detect the sarcasm. :-)