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Habitable planet around RedDwarf - Closest star

PostPosted: Fri 19 Aug 2016 08:43
by thebard
News report (if confirmed):

a habitable planet, around a red dwarf, which just happens to be the closest star to us . . .

http://www.universetoday.com/130276/ear ... iscovered/


PS - and SFF doesn't allow hab planets around red-dwarves table W6.04

Re: Habitable planet around RedDwarf - Closest star

PostPosted: Fri 19 Aug 2016 10:24
by southwestforests
Guess we'll find out soon,
The European Southern Observatory (ESO) plans on making the discovery, which has thus far been kept secret, public by the end of August.


Found this,
In October 2012, to widespread fanfare, the ESO announced the existence of Alpha Centauri Bb, which would have set a record for the closest planet outside the Solar System. Sadly, however, subsequent evidence led to the claim’s retraction. Understandably, this may have made the ESO particularly anxious to protect their high reputation by not making another unsubstantiated claim on a closely related topic. If the report is indeed true, the delay could represent a desire to triple-check the findings for errors before making an announcement.

Even Der Spiegel’s anonymous source said: “We were working at the limit of technically feasible measurement.”
http://www.iflscience.com/space/reports ... -neighbor/

Re: Habitable planet around RedDwarf - Closest star

PostPosted: Sat 20 Aug 2016 19:10
by Cralis
That's not entirely true. In SSF, a red dwarf star CAN have a T or ST planet. The planet must be tidelocked with the star and tidelocked with a "big" moon, and the planet must be mass 2 or 3. Then it is T or ST. What you want to look at is Table W6.04.2 :)

When we wrote SSF the concept of a "halo" habitable world wasn't known. Though in astrophysics it is increasingly being thought of as not only possible, but more probably than Earth-like habitable worlds, it has never been adopted for SSF. Thought I've been thinking about how that might happen...

As for Proxima Centauri, all they've said is that there is a potentially rocky world in the habitable zone of the star. That's all we know. Last I read, there wasn't even a spectral analysis yet. So the jury is still out on what it actually there.

But it's very exciting that it has planets :)

Re: Habitable planet around RedDwarf - Closest star

PostPosted: Wed 24 Aug 2016 19:18
by Moonsword
Quite exciting indeed. Interesting times!

Re: Habitable planet around RedDwarf - Closest star

PostPosted: Sat 27 Aug 2016 19:08
by aramis
There are several potential scenarios that should allow a habitable world at tidelocking range.

1) "Eyeball Earths" - tidelocked, but atmosphere circulates heat from the front to warm the back.

2) resonance lock - rotations and revolutions in a stable resonance lock.

3) tidelocked to a massive moon.

It's worth noting that Proxima B is at 0.05 AU. Mercury orbits Sol at about 0.3 AU... 6x as far, for a star that's 1/8 the mass. Mercury is in resonance but not actually tidelocked. Proxima B might not actually be tidelocked...

Note that the actual data is "Minimum mass 1.3 Earths"... maximum is suggested to be around 3 on several different vids; this is due to estimated inclination issues. That would make it possible to be potentially an ST and T or T & T...

Re: Habitable planet around RedDwarf - Closest star

PostPosted: Sun 28 Aug 2016 04:00
by Cralis
aramis wrote:There are several potential scenarios that should allow a habitable world at tidelocking range.

1) "Eyeball Earths" - tidelocked, but atmosphere circulates heat from the front to warm the back.


I've not heard this term before. I think you're referring to what I know as halo habitables. Where the surface facing the star is very hot, the side away from the star is very cold, and there is a small halo of habitable surface around the terminator and the air is constantly cycling from hot to cold and vice versa.

However, SSF doesn't currently allow for this type of habitable.

2) resonance lock - rotations and revolutions in a stable resonance lock.

3) tidelocked to a massive moon.


These are the types that SSF recognizes.

It's worth noting that Proxima B is at 0.05 AU. Mercury orbits Sol at about 0.3 AU... 6x as far, for a star that's 1/8 the mass. Mercury is in resonance but not actually tidelocked. Proxima B might not actually be tidelocked...


The tidelock ranges we have in our chart are generalized, but fairly accurate. We have Red Dwarf stars tidelocking out to 1 LM (or 11,160,000 KM) and Proxima B is at 7,479,900 KM. There is a pretty good chance it is tidelocked. It could have a moon and we still have no idea what the criteria are to create a halo habitable. So it's not all bad :)

Note that the actual data is "Minimum mass 1.3 Earths"... maximum is suggested to be around 3 on several different vids; this is due to estimated inclination issues. That would make it possible to be potentially an ST and T or T & T...


And the heavier it is, more realistically the more likely it is to be tidelocked. But yeah, it's would be interesting.