Comments on: The case of the brown star that's really red or possibly blue

By: Messier Tidy Upper

Messier Tidy Upper — Wed, 27 Jun 2012 07:35:21 +0000

Aha! Found it!

In the July 2012 ‘Sky &Telescope’ magazine article titled “Misfit Stars” by Kristina Grifantini. (Pages 22 -27) According to one caption :

“.. WISEP J1828+2650 currently the coldest known free-floating brown dwarf. A thermometer on this failed stars visible surface would read a lower temperature than that measured by a thermometer stuck in a person’s mouth.”

In the text it is described as one of 8 Y-class brown dwrfas six of which were discovered by the WISE space observatory. They add that it is “..only as warm as earth on a summer’s day : 300 K” (page 24) and another contender for literally coolest brown dwarf – WD 0806-661B – which orbits a white dwarf star is described as having “short sleeve conditions” as well! (Page 25.) 8)

Good article there that I’d highly recomend. Knew I’d read something about this recently!

By: Messier Tidy Upper

Messier Tidy Upper — Wed, 27 Jun 2012 07:02:01 +0000

@ ^ CharonPDX : Me too. Cold “stars” indeed!

Plus they’ve since found even colder brown dwarfs – room temperature – if my vague memory of reading something in one astronomy magazine suffices.

By: CharonPDX

CharonPDX — Thu, 26 Jan 2012 19:14:03 +0000

What amazes me is that this “star” is cooler than the surface of Venus!

By: The Star That The Greenhouse Effect Forgot « The Unbearable Nakedness of CLIMATE CHANGE

Mon, 01 Feb 2010 18:03:36 +0000

[...] Obviously there will soon be a much better explanation, but isn’t it peculiar that regarding “what may be the coolest sub-stellar body ever found outside our own solar system” with “a temperature estimate of about 441° Fahrenheit (227° Celsius)“, the explanation for some strange “color” effect in different infrared pictures is that “the atmosphere is cool enough that methane and steam absorb the light coming from below“? [...]

By: Troythulu’s Nu’z « The Call of Troythulu

Troythulu’s Nu’z « The Call of Troythulu — Mon, 01 Feb 2010 17:41:31 +0000

[...] The case of the brown star that’s really red or possibly blue — Here’s an awesome piece by the Bad Astronomer on a recently discovered pair of binary ‘brown dwarf’ substars and the unusual spectral readings from both. It looks as though they are very close in the stellar neighborhood, and Phil gives a nice explanation of some useful astronomical jargon… [...]

By: mike burkhart

mike burkhart — Mon, 01 Feb 2010 13:43:02 +0000

Some white stars apper green in color also the sun and moon can apper in diferent colors maybe some of this is that humans are one of few animals that can see in color on Earth

By: Ben Burningham

Ben Burningham — Sun, 31 Jan 2010 11:26:25 +0000

@ 44. Ned Wright

Careful with that distance, the paper that was posted by Scholz is not yet accepted for publication, and I suspect significant revisions will be required before it is.

I’m not sure how you’ve gone about calculating that Teff, but be aware that it is not a trivial step to go from the Spitzer magnitudes to fluxes for these objects, and then to effective temperature even given a distance. These objects do not have blackbody-like spectra.

But yes, WISE will find many objects this cool. We’re all very much looking forward to seeing what’s out there

and
@ 18. MadScientist

The subaru spectrum is the spectrum of SDSS1416B, and it has been corrected for the absorption due to the Earth’s atmosphere.

By: Pi-needles

Pi-needles — Sun, 31 Jan 2010 02:20:33 +0000

Having been thinking about the name “brown dwarfs” some more, I’ve come to the conclusion that the most accurate name for these objects would be “infra-red dwarfs” or even “heat dwarfs” instead.

After all their “redder than red” in terms of the electromagnetic spectrum and so that’s the next logical step there & its also accurately descriptive in terms of how we (mainly?) detect & view them correct?

Anyone with me for seeing if we can change the BD name to “IR / heat dwarfs”?

By: Messier Tidy Upper

Messier Tidy Upper — Sun, 31 Jan 2010 02:12:08 +0000

@ 36. Ben Burningham Says:

Just to throw a spanner in the works: SDSS1416A, the brighter component, might actually be a star. Our best estimate for its mass just now is right on the stellar/substellar boundary at about 75 times the mass of Jupiter, although this estimate also hangs on the age estimate for the system (which is about 10 billion years).

Thanks! That’s great info & link there – much appreciated.

By: Ned Wright

Ned Wright — Sun, 31 Jan 2010 00:45:15 +0000

Someone should refer to arXiv:1001.2743, an earlier paper by Scholz identifying this as an interesting object and giving a distance for the system 1416+13AB. Given the distance of 8 pc and the fluxes from Burningham etal, and assuming a radius of 0.1 R(sun) the effective temperature is more like 610-690 K. Definitely chicken flambe.

The B component will be a 60-70 sigma detection in WISE data. The A component is even brighter, and the separation will be resolved by WISE.