Try defining something darker than coal.
Astronomers have discovered a planet some 750 light years away (one light-year is about 6 trillion miles) so dark it reflects only one percent of all the sunlight that falls on it.
About the size of Jupiter, the giant gas planet called "TrES-2b" is even darker than coal, or according to how David Kipping of the Harvard-Smithsonian Center for Astrophysics puts it, "TrES-2b is considerably less reflective than black acrylic paint, so it's truly an alien world."
Although it’s pitch black, David Spiegel of Princeton University, who co-authored the paper reporting the find, also mentioned that the planet was so hot it emitted a "faint red glow, much like a burning ember or the coils on an electric stove."
The team made up by Kipping and Spiegel used data from NASA's Kepler telescope to determine how much light TrES-2b was reflecting. And although it is being considered as a remarkable finding, the team stated that it was still unclear what was making the planet so "extraordinarily dark."
According to National Geographic, Kipping said that "Some have proposed that this darkness may be caused by a huge abundance of gaseous sodium and titanium oxide, but more likely there is something exotic there that we have not thought of before."
The Kepler telescope, which was launched on May 7, 2009, has a mission lifespan of 3.5 years and was designed to discover Earth-like planets orbiting other stars.
Who knows, maybe next time it will spot a less dark and more habitable planet.