Earth may have a new neighbour, in the form of an Earth-like planet in a solar system only 16 light years away. The planet orbits a star named Gliese 832, and that solar system already hosts two other known exoplanets: Gliese 832B and Gliese 832C. The findings were reported in a new paper by Suman Satyal at the University of Texas, and colleagues J. Gri?th, and Z. E. Musielak.
Gliese 832B is a gas giant similar to Jupiter, at 0.64 the mass of Jupiter, and it orbits its star at 3.5 AU. G832B probably plays a role similar to Jupiter in our Solar System, by setting gravitational equilibrium. Gliese 832C is a Super-Earth about 5 times as massive as Earth, and it orbits the star at a very close 0.16 AU. G832C is a rocky planet on the inner edge of the habitable zone, but is likely too close to its star for habitability. Gliese 832, the star at the center of it all, is a red dwarf about half the size of our Sun, in both mass and radius.
?2016-04-21T10:22:16Z
That's nice. If you're going to copy the text of a website verbatim, though, you should attribute the source or post a link to it, like this: http://www.universetoday.com/128525/earth-like-planet-16-light-years-away/ Second, this is a Q&A site, and not a news aggregator, so...what's your question? . My question for you, or the authors of the paper or anyone else, would be how we make the leap from 'hypothetical planet in the habitable zone' to 'Earth-like'? When the uninformed layman hears 'Earth-like', he starts imagining oceans and atmosphere and bright sunny days with birds fluttering through the trees, while the reality is that we have no idea what the surface conditions on any of these newly-discovered worlds are. . .
But the host star is a red dwarf. There isn't really much hope that a red dwarf star could host a habitable planet. Because a planet in the habitable zone because it would be very close to its star and hence tidally locked. with one face permanently facing the star.
Plus at 5 earth masses, it would likely have high surface gravity. As of now, there are no "earth-like" planets known.
If one was found it would be the number 1 news item on the news.
Astronomers have an extremely loose definition of what is an "Earth-like" planet. To them, an Earth-like planet is one that is rocky (similar to the four inner planets of our solar system), orbits within a star's habitable zone (the so-called "Goldilocks zone", where the planet's mean surface temperature is such that liquid water MIGHT exist on its surface) and whose mass is a low multiple of Earth's mass. This says nothing about the possible composition of a planet's atmosphere, the physics or chemistry of the planet's surface environment or many other factors that must be taken into account in order to call a planet truly Earth-like.
"Earth-like" basically only means that it is the right size and orbits in right zone that it could sustain life like Earth has. But it does not mean that it can actually support life. It still needs to have water and the right mix in the atmosphere to really be habitable.
And at 16 light years away, it will be a long, long trip at our current level of technology. It would take hundreds of generations to reach it. And by the time they did, it's possible no one on Earth will be around any longer to remember sending it.
Note very carefully the use of the words "may" and "probably" in the article. I mean: a red dwarf and a planet five times that of Earth: get real folks.
We get this all the time in the popular media about any speculative fiction based on a few dodgy observations. Then the whole shebang just fades into oblivion and the media turns to the next piece of sensationalism.
Treat these articles as masturbatory astronomy:- quick thrill then nothing until the next magazine picture.