Astronomers uncover alien world so 'extraordinarily dark' it makes coal look shiny
No replies to this topic
Posted 12 August 2011 - 09:49 AM
Astronomers have discovered the darkest known planet. The exoplanet, known as TrES-2b, reflects less than 1 per cent of light, which makes it darker than any other planet or moon. The discovery, detailed in the journal Monthly Notices of the Royal Astronomical Society, was made by analysing data from Nasa's Kepler spacecraft, which provides extremely precise measurements on the brightnesses of faraway stars.
'TrES-2b is considerably less reflective than black acrylic paint, so it's truly an alien world,' David Kipping of the Harvard-Smithsonian Center for Astrophysics (CfA) told Science Daily. TrES-2b, a gas exoplanet roughly the size of Jupiter, is around 750 light years away and was discovered in 2006 by the Trans-Atlantic Exoplanet Survey; hence its less-than-catchy name.
The reason it differs from other similar-sized planets is that Jupiter, for example, is surrounded by ammonia clouds that reflect more than one third of its sunlight. TrES-2b has no ammonia clouds to reflect light because it is extremely hot. It orbits its star - GSC 03549-02811 - at a relatively intimate five million kilometres, which means it exhibits temperatures of up to 1,000C. Instead, it has an atmosphere made up of chemicals such as vaporized sodium, potassium and gaseous titanium oxide, which absorb light, but that still does not explain the planet's extreme blackness.
0 user(s) are reading this topic
0 members, 0 guests, 0 anonymous users