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Earth-Like Planet, With Ambitious Life Possibility, Found Orbiting the Star Next Door (nature.com)
There's another Earth out there. For real, this time. Astronomers announced on Wednesday that they had detected a planet orbiting Proxima Centauri, the closest neighbor to our solar system. Intriguingly, the planet is in the star's "Goldilocks zone," they said, a place that hints that it may not be too hot nor too cold. Which in turn means that liquid water could exist at the surface, and by extension, it raises the possibility of life. Nature reports:"The search for life starts now," says Guillem Anglada-Escude, an astronomer at Queen Mary University of London and leader of the team that made the discovery. Humanity's first chance to explore this nearby world may come from the recently announced Breakthrough Starshot initiative, which plans to build fleets of tiny laser-propelled interstellar probes in the coming decades. Travelling at 20% of the speed of light, they would take about 20 years to cover the 1.3 parsecs from Earth to Proxima Centauri. Proxima's planet is at least 1.3 times the mass of Earth. The planet orbits its red-dwarf star -- much smaller and dimmer than the Sun -- every 11.2 days. "If you tried to pick the type of planet you'd most want around the type of star you'd most want, it would be this," says David Kipping, an astronomer at Columbia University in New York City. "It's thrilling."Much about the planet is still unknown. Astronomers have some ideas about its size and distance from its parent star. Scientists say they are working off computer models that offer mere hints of what's possible. Also, there's no picture available for this planet as of yet.
A planet this close to the star will be tidally locked, resulting in blast furnace heat on one side and near absolute zero cold on the other. There also will be gargantuan amounts of UV and radiation from flares, rendering this planet a barren wasteland and unfit to support any type of life.
Those relativistic postage stamp sized probes are a dream at present. Long before we could develop the technology for this, or get funding, we will study this planet with the advanced space-based instruments with capabilities far beyond anything now existing. No probe will be sent until we reach the limit of what we can do within our own solar system - nothing is faster than analyzing the light that already gets here, and even the most extravagant telescopic system will be cheaper than the probe project and all its supporting infrastructure.
That leads us to consider the HABEX Mission a pretty cool project under development using the huge and really cool looking Starshade vehicle to provide a coronagraph for a telescope in a separate vehicle thousands of kilometers away. Having a nearby target like this gives leverage with Congress to appropriate the funds.
Second class citizen of the New Gilded Age
It MIGHT be habitable. It MIGHT have an atmosphere. It MIGHT have water.
Chances are, it's actually tidally locked. One side gets daylight all the time and the other... well... it doesn't. It probably has had it's atmosphere stripped away. If it has water then it will all be frozen on the dark side (water evaporates on the hot side and gets locked as ice in the dark side).
Theoretically it could be a hot, but livable (except for being arid) 30C average on the light side and cold (but livable) -30C average on the dark side. Theoretically there is a comfortable zone half way in the transitional area. Don't get me wrong, this is by far our best chance at extra-solar life so far- but odds are you couldn't board a spaceship with a tent and some potatoes and start living there tomorrow as a farmer.
Definitely a great place to send a probe if we ever get the technology.
"That's the way to do it" - Punch
I love the whole "it's only 20 years if you travel at 20% of the speed of light!" part. It makes it sound so close. But you're not going to snap your fingers and jump right to 20% of the speed of light from one second to the next. That's 6,114,064.6 standard Earth g-forces! You'd be much better off having a slow, steady acceleration all the way there and a slow, steady acceleration all the way back. Unless I did the math wrong, you'd need to maintain about 0.38 m/s^2 (yeah, I rounded - I'm not the one sending the craft) the entire trip. ...
The interstellar space probe concept mission they are referencing is this one by Philip Lubin. The scheme has the 70 gigawatt launching lasers accelerating a tiny wafer thin probe to 20% c in 10 minutes, which is about 10,000 gees. A tiny wafer thin structure can handle that. And no, there is no slowing down. These things fly through the target system at 0.20 c, and keep on going.
Second class citizen of the New Gilded Age
and that right there is the whole problem with humanity. I hope your grandchildren enjoy warm climates.