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Fraser
2006-Mar-23, 04:42 AM
SUMMARY: Astronomers have discovered a brown dwarf in our galactic neighbourhood, only 12.7 light years away - this makes it the second closest brown dwarf ever discovered. The failed star is circling another star that was only recently discovered in the southern constellation Pavo. The primary star is small, with only 1/10th the mass of our Sun, and the brown dwarf orbits at 4.5 times the distance of the Earth to the Sun.

View full article (http://www.universetoday.com/am/publish/bdwarf_near_sun.html)
What do you think about this story? post your comments below.

antoniseb
2006-Mar-23, 01:18 PM
It will take a lot of years for this object to make an orbit around the primary. Jupiter takes 12 to go around the Sun, this thing is about as far from its star as Jupiter is from the Sun, and it's star has 1/10 the mass of the Sun. One complete orbit should take about a century.

GOURDHEAD
2006-Mar-23, 02:29 PM
The primary must be a "beige dwarf".

galacsi
2006-Mar-23, 09:29 PM
Hail to science ! Now we know that red dwarfs are pink and brown dwarfs are blue !

jhwegener
2006-Mar-23, 09:38 PM
Could there be a number of such brown dwarfs, or other types of objects smaller than ordinary stars, nearer to our sun than the closest neighbour known?(about 4 ly). May such "small" objects be more common in our galaxy than visible stars? The fact that such "close" objects have not been discovered earlier, rises questions of possibillity of more discoveries in our neighborhood.Brown drarfs or objects similar to "our" gas planets.

baric
2006-Mar-23, 09:49 PM
yes, there could be...

Gerald Lukaniuk
2006-Mar-23, 11:46 PM
This little critter is probably a lot more important than astronomers think and its an insult to call her a "failed star". The energy source or sources that warm these objects have yet to be pinned down and there is a opportunity from spectral analysis of fine surface details to find out what is really going on. There would be physics not seen on earth that is also blinded out on the sun. The anwers to the riddles that conjure up demons like dark energy would probably more likely be found here then 11 billion light years away.

antoniseb
2006-Mar-24, 12:49 AM
The anwers to the riddles that conjure up demons like dark energy would probably more likely be found here then 11 billion light years away.

Hi Gerald, Can you elaborate about what you mean by your dark energy comment? I'm suspicious that this is representing an Alternative Theory. If this is the case, perhaps you should bring this up in the ATM section.

Saluki
2006-Mar-24, 09:30 PM
http://spaceflightnow.com/news/n0603/22browndwarf/


Astronomers have discovered a unique "brown dwarf" right in our solar neighborhood.
If your city were the galaxy, it would be like finding someone you didn't know about living upstairs in your house, one of the discoverers said.
The rare object is only 12.7 light years from Earth, circling a primary star that itself was discovered only recently in the southern hemisphere constellation Pavo (the Peacock).

antoniseb
2006-Mar-24, 10:02 PM
Part of the problem with merging threads like this that people keep creating new copies in the Astronomy section when they don't see it there.

A.DIM
2006-Mar-25, 02:02 PM
Could there be a number of such brown dwarfs, or other types of objects smaller than ordinary stars, nearer to our sun than the closest neighbour known?(about 4 ly). May such "small" objects be more common in our galaxy than visible stars? The fact that such "close" objects have not been discovered earlier, rises questions of possibillity of more discoveries in our neighborhood.Brown drarfs or objects similar to "our" gas planets.

Given that binary systems, as well as brown dwarves(?), are more prevalent in the cosmos, and coupled with various tantalizing clues in our own system, I suspect our solar system may contain a brown dwarf.

Disinfo Agent
2006-Mar-25, 02:07 PM
Dwarfs.

I suspect a brown dwarf in our own solar system would have been detected long ago.

antoniseb
2006-Mar-25, 02:27 PM
I suspect a brown dwarf in our own solar system would have been detected long ago.

There was a recent paper I'd seen which declared that we could be certain that there was no brown dwarf closer than 40,000 AU, based on how bright it would be in various infrared surveys.

A.DIM
2006-Mar-25, 03:16 PM
I'd be interested in reading it, if there's a link.

Matese presented a paper recently that suggests such a companion is likely to have been recorded already by IRAS or 2MASS:

A wide-binary solar companion as a possible origin of Sedna-like objects (http://www.ucs.louisiana.edu/~jjm9638/acm2005/matese_acm2005.pdf).

antoniseb
2006-Mar-25, 05:44 PM
I'd be interested in reading it, if there's a link.


I don't have a link, sorry. It was interesting enough to lodge in my memory, but not enough to note the link, and a year or two have gone by.

Gerald Lukaniuk
2006-Mar-26, 07:30 PM
Hi Gerald, Can you elaborate about what you mean by your dark energy comment? I'm suspicious that this is representing an Alternative Theory. If this is the case, perhaps you should bring this up in the ATM section.
Certainly the Big Bang theory losses crediblility by invoking something as contradictory as Dark energy. How can energy or motive force produce actions that don't somehow produce luminance such as through friction. Energy that can be felt but not seen? Perhaps such a phenomenon could be seen in a lowly illuminated energy producing envirorment such as a brown dwarf.

antoniseb
2006-Mar-26, 11:47 PM
...Perhaps such a phenomenon could be seen in a lowly illuminated energy producing envirorment such as a brown dwarf.

What would you expect to see in the way of illumination from dark energy in a brown dwarf that you couldn't see in Jupiter, or perhaps under two miles of Antarctic ice?

Gerald Lukaniuk
2006-Mar-27, 08:24 PM
What would you expect to see in the way of illumination from dark energy in a brown dwarf that you couldn't see in Jupiter, or perhaps under two miles of Antarctic ice?
There are certain indicators that there are energy producing processes going on in dwarfs beyond geothermal chemical or known fission. Say one of these critters is 10 times bigger than jupiter and 1 tenth the sun if I'm reading right they would be producing more than one hundredth the energy jupiter or 1/1000 the energy of earth. At a surface temp of 700 or so it seems unlikely that H fusion occurs as luminosity would break through boiling off a jupiter like gas envelope. If they are rocky there would be know reason to assume that the would contain a higher percentage of fissionable material than us an our rocky neibours. To use a bad hunting cliche its better too hang around a watering hole than search the woods. We obviously don't see any indications of dark energy production yet on earth. under the ice or on Jupiter. It might be being produced on in the sun but all the other "bright" energy processes might obscur it. All the energy processes such as fission that oncur on a white dwarf should be occuring in a star. Thus even if "dark energy" effects aren't seen on a dwarf we can still try to gauge "dark energy" production on a star by subtracting a "dwarf energy coefficient" and known energy producing processes on that stars from say apparent losses of stellar mass. Unless Big Bang enthusiasts want to refute E=mc2 and incur the rath of the Albert Einstein fan club.

antoniseb
2006-Mar-27, 08:47 PM
Say one of these critters is 10 times bigger than jupiter and 1 tenth the sun if I'm reading right they would be producing more than one hundredth the energy jupiter or 1/1000 the energy of earth. At a surface temp of 700 or so it seems unlikely that H fusion occurs as luminosity would break through boiling off a jupiter like gas envelope.

Jupiter, and Brown Dwarfs, are giving off energy as they shrink. As material falls, it heat up the gas beneath it. As it radiates this heat away, the pressure can drop again and it falls again. This is a continuous process, and is the main source of heat for a brown dwarf or gas giant. This heat of contraction is so large that it would mask out any tiny effect you might be seeing from Dark Energy... though personally, I don't think Dark Energy work in a way that would result in heat in a Brown Dwarf.

Gerald Lukaniuk
2006-Mar-28, 12:44 AM
Jupiter, and Brown Dwarfs, are giving off energy as they shrink. As material falls, it heat up the gas beneath it. As it radiates this heat away, the pressure can drop again and it falls again. This is a continuous process, and is the main source of heat for a brown dwarf or gas giant. This heat of contraction is so large that it would mask out any tiny effect you might be seeing from Dark Energy... though personally, I don't think Dark Energy work in a way that would result in heat in a Brown Dwarf.
Well maybe now we can measure this so called heat producing shrinkage which ofcourse does't explain geothermal energy on earth.

baric
2006-Mar-28, 05:04 PM
Well maybe now we can measure this so called heat producing shrinkage which ofcourse does't explain geothermal energy on earth.

Right. But the Earth-Moon system creates Shadow Energy however most of it is lost in the glare of the nuclear processes that generate geothermal energy in the Earth. You can nevertheless calculate the amount of shadow energy by subtracting out the known reflective energy processes and multiplying by a shadow energy co-efficient, and this will refute the existence of Hawking radiation for gray bodies (black bodies dominated by dark energy) that is unless you are a fan of the Stephen Hawking club.

It's all described in great detail at my website at www.Iamageniusinmyownmind.com

Gerald Lukaniuk
2006-Mar-28, 07:02 PM
Sounds like you've got a good idea but I couldn't get on your site. Unfortunately I'm getting wacky sci fantasy use of the words Shadow Energy. In cases where we are expected to beleive in "Boo-jums" (Lewis Carol) like dark energy, sterile neutrinos, gray energy by "thinkers" who seem to be playing with words rather than doing any real deduction the most useful thing we can do is nether to scoff at their naive ideas or passing of half baked speculation as a theory like they do is to take a clue from the great master himself. "When you've considered all possibilities and eliminated the impossible what ever is left no matter how implausible must be true". This its out there but you can't eve see it nonsense has got to stop if the guys in white coats want to call themselves scientist. Using subtractive methods to narrow down their hiding places is the best tool we have in hunting down these Snarks.

five_distinct
2006-Mar-28, 09:34 PM
Right. But the Earth-Moon system creates Shadow Energy however most of it is lost in the glare of the nuclear processes that generate geothermal energy in the Earth. You can nevertheless calculate the amount of shadow energy by subtracting out the known reflective energy processes and multiplying by a shadow energy co-efficient, and this will refute the existence of Hawking radiation for gray bodies (black bodies dominated by dark energy) that is unless you are a fan of the Stephen Hawking club.

It's all described in great detail at my website at www.Iamageniusinmyownmind.com

Hahaha

Fram
2006-Mar-29, 02:40 PM
I'd be interested in reading it, if there's a link.

Matese presented a paper recently that suggests such a companion is likely to have been recorded already by IRAS or 2MASS:

A wide-binary solar companion as a possible origin of Sedna-like objects (http://www.ucs.louisiana.edu/~jjm9638/acm2005/matese_acm2005.pdf).

"Such a companion", according to Matese (http://www.ucs.louisiana.edu/~jjm9638/), has a mass of 3 to 5 times Jupiter's, and is thus clearly not a brown dwarf (which needs a mass of about 13 times Jupiter's).

The estimated mass of the companion puts it below the nominal brown dwarf limit (~ 13 MJupiter ) where deuterium fusion can occur and would make it a planet in that context

Gerald Lukaniuk
2006-Mar-29, 08:09 PM
Hahaha
Your must be in one of them there inverted gravitational anomalities cause your universal chronometer is running fast.