Interstellar Objects-What are they?

[thebigcat]

Some years ago, about 1998, my then housemate drew to my attention an article in our local newspaper about several objects located in interstellar space, possibly through gravitational lensing, which were much more massive than any planets and far too dark and cold to be stars. I remember from the article that the largest was figured to be several Jupiter-masses. My immediate speculation based on the limited information was that they were accretions of dust, solar-wind particles and ice collecting at places where gravitational attraction from nearby stars is weak or cancelling, such as with LaGrangian Points. My housemate immediately remarked that it sounded like I was talking about dust bunnies, so we started referring to the objects as "Hypothetical Interstellar Dust Bunnies".<br /><br />Unfortunately, given that we only had the small amount of information from the newspaper article (You know how that goes), we had no real terms to define a solid search criterion and have been unably to determine anything further about the objects. I am hoping that anyone who knows anything more about these objects would be able to point me in the direction of pertinant information.<br /><br />Thanks<br />Cat. <div class="Discussion_UserSignature"> </div>

 

[Saiph]

Brown dwarfs may be what you heard about.<br /><br />They're essentially failed stars (they never got big enough for sustained hydrogen fusion). <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[alokmohan]

Can you give reference?Literature on brown dwarf is little.

 

[harmonicaman]

One Brown Dwarf page.

 

[thebigcat]

Fascinating. This could be it, although I do recall that the objects mentioned in the newspaper article being too cold to be any type of star. However, the copy editor who assembled the item could have taken "Substellar" to mean "not a star", unaware that astronomical science defines a star as any object that radiates more energy than it recieves.<br /><br />The page mentions a disdance 40au. That's so close that I would almost expect it to be in solar orbit. Could that be accurate or did the page's creator drop a zero?<br /><br />ETA: Ah, I see. 40AU from the star it orbits. Not 40 AU from here.<br /><br />One of the links on the page is to a table of Brown Dwarf stars, and I notice that one of them, S Ori 47, is listed as being between 10-20 Jupiter Masses. This is on a level with some of the extra-solar planets which are listed as super giants. It also has a projected age of between 1 and 3 million years. Talk about an infant. <div class="Discussion_UserSignature"> </div>

 

[nexium]

"Radiates more energy than it receives" is a poor definition for star. Almost everything does that, short term and/or long term.<br />A 100 steller mass object may be in the steller nursery, so failed stars, and lesser bodies are often ejected by sling shot manuver, into intersteller space. In a few million years, these cool below star temperature, unless they collide with lots of matter. These may be more numerous than the stars we can see. Neil<br />