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baric
2010-Jul-19, 03:40 AM
The latest news from the WISE survey includes that tantalizing blurb!

http://www.telegraph.co.uk/science/space/7894247/Nasa-elated-after-new-telescope-uncovers-previously-invisible-space-objects.html

I'm assuming that brown dwarfs have to be fairly close, but I guess this rules out the Niburu possiblility?

edit: POTENTIAL brown dwarfs! sorry for leaving that out of the subject line :/

AndreasJ
2010-Jul-19, 06:58 AM
I don't see anything in the article to rule out that one (or more!) of those candidate objects could be a distant companion of the Sun.

However, no actual distant companion could behave as the Nibiru of 2012 myth is supposed to do, so in that sense there was never a Nibiru possibility to rule out.

baric
2010-Jul-19, 12:23 PM
Well, that's true of course. You would think if one of the dwarfs was a solar companion then it would have been a bigger part of the story. In fact, any large body closer than the AC system would have been a big story!

AndreasJ
2010-Jul-19, 02:00 PM
Well, that's true of course. You would think if one of the dwarfs was a solar companion then it would have been a bigger part of the story. In fact, any large body closer than the AC system would have been a big story!

The story doesn't give any details, but part of the reason they're candidates is probably that they can't tell a distant and (comparatively) bright object from a nearby and dim one.

baric
2010-Jul-19, 02:44 PM
The story doesn't give any details, but part of the reason they're candidates is probably that they can't tell a distant and (comparatively) bright object from a nearby and dim one.

oh, good point! I guess they need more time to track the motion?

Nereid
2010-Jul-19, 02:48 PM
The latest news from the WISE survey includes that tantalizing blurb!

http://www.telegraph.co.uk/science/space/7894247/Nasa-elated-after-new-telescope-uncovers-previously-invisible-space-objects.html

I'm assuming that brown dwarfs have to be fairly close, but I guess this rules out the Niburu possiblility?

edit: POTENTIAL brown dwarfs! sorry for leaving that out of the subject line :/
There's nothing* published, or even presented at a conference, yet, on WISE and brown dwarf discoveries, so we have nothing to work with.

In fact, the non-moving object findings aren't due to be released until April 2011!

No doubt some of the scientists are already following up the WISE observations of brown dwarf candidates (e.g. this hint (http://adsabs.harvard.edu/abs/2010sptz.prop70062K)), but that just tells us what the plans are, not what the results are.

* that I could find

baric
2010-Jul-19, 05:18 PM
No doubt some of the scientists are already following up the WISE observations of brown dwarf candidates (e.g. this hint (http://adsabs.harvard.edu/abs/2010sptz.prop70062K)), but that just tells us what the plans are, not what the results are.

Thanks for the link. It's just an abstract, but I'm curious if you could parse one comment in it for me.

Our WISE selection process uses the W1 (3.4 um) and W2 (4.6 um) color to identify brown dwarf candidates; the resulting, red W1-W2 colors are indicative of deep methane absorption at 3.3 um. For our coldest sources, which are the most important for deciphering the low-mass cutoff of star formation, these will be color limits because the candidate is undetected in W1. Spitzer can easily provide much deeper imaging and measure robust ch1-ch2 colors, which are complementary to W1-W2.

ok, actually two questions.

a) the first bolded part...to make sure I understand. WISE is doing surveys at 3.3um and 4.6um. If they see a body at 4.6um but NOT 3.3um, that means that it has methane in its atmosphere which is just suppressing the 3.3um image because of methane's 3.4um line. Thus, it is a cooler brown dwarf. Is that an accurate assessment of the technique?

b) What are ch1-ch2 colors? I have no idea on this one :P

Nereid
2010-Jul-19, 06:33 PM
Thanks for the link. It's just an abstract, but I'm curious if you could parse one comment in it for me.


ok, actually two questions.

a) the first bolded part...to make sure I understand. WISE is doing surveys at 3.3um and 4.6um. If they see a body at 4.6um but NOT 3.3um, that means that it has methane in its atmosphere which is just suppressing the 3.3um image because of methane's 3.4um line. Thus, it is a cooler brown dwarf. Is that an accurate assessment of the technique?
Close.

There may be many reasons why a WISE object has a red W1-W2 colour; being a brown dwarf (cool, methane atmosphere) is one, very likely, reason.



b) What are ch1-ch2 colors? I have no idea on this one :P
They refer to two (of four) IRAC* colour filters (http://ssc.spitzer.caltech.edu/irac/calibrationfiles/spectralresponse/).

* InfraRed Array Camera

baric
2010-Jul-19, 11:48 PM
Close.

There may be many reasons why a WISE object has a red W1-W2 colour; being a brown dwarf (cool, methane atmosphere) is one, very likely, reason.


They refer to two (of four) IRAC* colour filters (http://ssc.spitzer.caltech.edu/irac/calibrationfiles/spectralresponse/).

* InfraRed Array Camera

oooh,, ok. I just picked up on that terminology. When you say "W1-W2 color", you are treating the W1 to W2 range as a shifted visible spectrum where W1 is blue and W2 is red. Thus, a red "W1-W2" is one where W1 (the blue) has been suppressed.

That wasn't quite so obvious to me at first, but now that abstract makes a lot more sense.

Nick Theodorakis
2010-Jul-20, 01:03 AM
I don't see anything in the article to rule out that one (or more!) of those candidate objects could be a distant companion of the Sun.

However, no actual distant companion could behave as the Nibiru of 2012 myth is supposed to do, so in that sense there was never a Nibiru possibility to rule out.

Maybe he meant "Nemesis" rather than "Nibiru."

Nick

baric
2010-Jul-20, 02:34 AM
Maybe he meant "Nemesis" rather than "Nibiru."

Nick

Actually --- I wanted to include both but had a brain lock and couldn't remember "Nemesis" << getting old

Personally, I am hoping that we do find a brown dwarf in our system so all of the CT nuts can finally have their exultant moment in the Sun. Then, as we gain more data and find out that Nemesis/Nibiru is harmless, the CT finally dies and takes its proper place in myth.