Three Earth-like Planets discovered orbiting Dwarf Star

[abu afak]

A whole new category of star in which to look for 'Goldilocks' zone planets.
This system a fairly close 40 ly.

Three Earth-like planets discovered orbiting dwarf star - CNN.com
By Ashley Strickland, CNN
Mon May 2, 2016
(Artist Renderings at link)

For the first time, researchers have discovered three potentially habitable, Earth-like worlds orbiting an ultracool dwarf star 40 light-years away in another star system, according to a study published in the journal Nature.

The ultracool dwarf star, known as TRAPPIST-1, isn't the kind of star scientists expected to be a hub for planets. It's at the end of the range for what classifies as a star: half the temperature and a tenth the mass of the sun. TRAPPIST-1 is red, barely larger than Jupiter and too dim to be seen with the naked eye or even amateur telescopes from Earth.

But these tiny stars, along with brown dwarfs, are long-lived, common in the Milky Way and represent 25-50% of stellar objects in the galaxy, said study researcher Julien de Wit, a postdoctoral associate with MIT's Department of Earth, Atmospheric and Planetary Sciences. They were largely overlooked until researcher Michaël Gillon of the University of Liège in Belgium decided to take a risk and study the space around one of these dwarves. It paid off. Over the course of 62 nights from September to December 2015, researchers led by Gillon used a telescope, also called TRAPPIST (transiting planets and planetesimals small telescope), to observe its starlight and changes in brightness. The team saw shadows, like little eclipses, periodically interrupting the steady pattern of starlight. Using a telescope that can detect infrared light added an advantage that visible light camera programs don't provide.
[.......]
The planets are about the size of Earth and given the proximity of two of them to the dwarf star, they receive about four times the amount of radiation than we do from the sun, which suggests they are in the "habitable zone." According to Burgasser, the "habitable zone," determines how close a planet is to the star that it orbits and given the temperature of the planet based on that proximity, it could have water on the surface. This core ingredient for life as we know it also suggests there could be an atmosphere and habitable regions on the planets themselves. Less is known about the third outer planet, which receives twice the amount of radiation that Earth does, but it is potentially in the habitable zone as well.
[.......]​

 

[sealybobo]

A whole new category of star in which to look for 'Goldilocks' zone planets.
This system a fairly close 40 ly.

Three Earth-like planets discovered orbiting dwarf star - CNN.com
By Ashley Strickland, CNN
Mon May 2, 2016
(Artist Renderings at link)

For the first time, researchers have discovered three potentially habitable, Earth-like worlds orbiting an ultracool dwarf star 40 light-years away in another star system, according to a study published in the journal Nature.

The ultracool dwarf star, known as TRAPPIST-1, isn't the kind of star scientists expected to be a hub for planets. It's at the end of the range for what classifies as a star: half the temperature and a tenth the mass of the sun. TRAPPIST-1 is red, barely larger than Jupiter and too dim to be seen with the naked eye or even amateur telescopes from Earth.

But these tiny stars, along with brown dwarfs, are long-lived, common in the Milky Way and represent 25-50% of stellar objects in the galaxy, said study researcher Julien de Wit, a postdoctoral associate with MIT's Department of Earth, Atmospheric and Planetary Sciences. They were largely overlooked until researcher Michaël Gillon of the University of Liège in Belgium decided to take a risk and study the space around one of these dwarves. It paid off. Over the course of 62 nights from September to December 2015, researchers led by Gillon used a telescope, also called TRAPPIST (transiting planets and planetesimals small telescope), to observe its starlight and changes in brightness. The team saw shadows, like little eclipses, periodically interrupting the steady pattern of starlight. Using a telescope that can detect infrared light added an advantage that visible light camera programs don't provide.
[.......]
The planets are about the size of Earth and given the proximity of two of them to the dwarf star, they receive about four times the amount of radiation than we do from the sun, which suggests they are in the "habitable zone." According to Burgasser, the "habitable zone," determines how close a planet is to the star that it orbits and given the temperature of the planet based on that proximity, it could have water on the surface. This core ingredient for life as we know it also suggests there could be an atmosphere and habitable regions on the planets themselves. Less is known about the third outer planet, which receives twice the amount of radiation that Earth does, but it is potentially in the habitable zone as well.
[.......]​

NASA's Kepler mission has verified 1,284 new planets. This is the single largest finding of planets to date. This more than doubles the number of confirmed planets from Kepler and gives us hope that somewhere out there, around a star much like ours, we can eventually discover another Earth.

Analysis was performed on the Kepler space telescope which identified 4,302 potential planets. For 1,284 of the candidates, the probability of being a planet is greater than 99 percent – the minimum required to earn the status of “planet.” An additional 1,327 candidates are more likely than not to be planets, but they do not meet the 99 percent threshold and will require additional study. The remaining 707 are more likely to be some other astrophysical phenomena. This analysis also validated 984 candidates previously verified by other techniques.

Before the Kepler space telescope launched, we did not know whether exoplanets were rare or common in the galaxy. In the newly-validated batch of planets, nearly 550 could be rocky planets like Earth, based on their size. Nine of these orbit in their sun's habitable zone, which is the distance from a star where orbiting planets can have surface temperatures that allow liquid water to pool. With the addition of these nine, 21 exoplanets now are known to be members of this exclusive group.