WISE: Wide-Field Infrared Survey ExplorerWISE HomeWISE: Wide-Field Infrared Survey ExplorerWISE: Wide-Field Infrared Survey Explorer
Mission Science News & Events Education & Outreach Multimedia Gallery For Astronomers
WISE: Wide-Field Infrared Survey Explorer
spacer
    WISE Home
divider
WISE Multimedia Gallery Images
divider
Movies & Simulations
divider
Slideshows
divider
Podcasts
divider
WWT Guided Tour
     
WISE Multimedia Gallery

Download Options:

small (38K) 400 x 200 JPEG
medium (74K) 800 x 400 JPEG
large (163K) 1600 x 800 JPEG
original (5M) 6000 x 3000 TIFF

 

WISE

Multimedia Gallery

A Trio of Brown Dwarfs

This artist's conception illustrates what brown dwarfs of different types might look like to a hypothetical interstellar traveler who has flown a spaceship to each one.

August 23, 2011

This artist's conception illustrates what brown dwarfs of different types might look like to a hypothetical interstellar traveler who has flown a spaceship to each one. Brown dwarfs are like stars, but they aren't massive enough to fuse atoms steadily and shine with starlight -- as our sun does so well.

On the left is an L dwarf, in the middle is a T dwarf, and on the right is a Y dwarf. The objects are progressively cooler in atmospheric temperatures as you move from left to right. Y dwarfs are the newest and coldest class of brown dwarfs and were discovered by NASA's Wide-field Infrared Survey Explorer, or WISE. WISE was able to detect these Y dwarfs for the first time because it surveyed the entire sky deeply at the infrared wavelengths at which these bodies emit most of their light.

The L dwarf is seen as a dim red orb to the eye. The T dwarf is even fainter and appears with a darker reddish, or magenta, hue. The Y dwarf is dimmer still. Because astronomers have not yet detected Y dwarfs at the visible wavelengths we see with our eyes, the choice of a purple hue is done mainly for artistic reasons. The Y dwarf is also illustrated as reflecting a faint amount of visible starlight from interstellar space.

In this rendering, the traveler's spaceship is the same distance from each object. This illustrates an unusual property of brown dwarfs -- that they all have the same dimensions, roughly the size of the planet Jupiter, regardless of their mass. This mass disparity can be as large as fifteen times or more when comparing an L to a Y dwarf, despite the fact that both objects have the same radius.

The three brown dwarfs also have very different atmospheric temperatures. A typical L dwarf has a temperature of 2,600 degrees Fahrenheit (1,400 degrees Celsius). A typical T dwarf has a temperature of 1,700 degrees Fahrenheit (900 degrees Celsius). The coldest Y dwarf so far identified by WISE has a temperature of less than about 80 degrees Fahrenheit (25 degrees Celsius).

Image credit: NASA/JPL-Caltech

 
       
   
 
       
    Return to Image Index  
WISE
logos
spacer
UCLA JPL
Last updated 1/31/12 © UC Regents

NASA