Water found on exo planet in habitable zone

[Stu]

Interesting new find...

BBC News - Water found on 'mind-blowing' world
https://www.bbc.co.uk/news/science-environment-49648746

[Ouroboros]

Interesting. I think I'll be more excited when they discover oxygen in an exoplanet's atmosphere. 

Does anyone know where this exoplanet is. I know it's 124LY away and that it orbits a red dwarf. The star is  I 

[Gina]

Heard about this on the news.

[Ouroboros]

52 minutes ago, KevS said:

Ouroboros,

may be of interest. 

https://www.aanda.org/articles/aa/full_html/2017/12/aa31558-17/aa31558-17.html

K

P.S. It's somewhere in Leo.

Lots of info there. Thanks. And for where it is. I just wondered. 

[happy-kat]

The best thing would be it's a hoax as we can't look after the water we have.

[Chris]

Just been reading about this, thanks Stu. Goldy locks zone, rocky, water and, methane, all very good signs! 

[Star101]

This is where BBC appears to have got the info from.

Water vapour on Exoplanet

[Stub Mandrel]

The star K2-18 has appeared as a 'custom object' in Stellarium, but it's virtually on the far side of the sun so a few months before we can get a shot at it! No data on magnitude and it's a dwarf so it may be very faint.The only clue is that the brightest pixel received 1,900 electrons in 103 seconds, this is in IR but it should be detectable with an IR sensitive camera!

Weird how the paper talks about the planet K2-18b but doesn't explicitly mention the name of its parent star.

[JamesF]

25 minutes ago, Stub Mandrel said:

The star K2-18 has appeared as a 'custom object' in Stellarium, but it's virtually on the far side of the sun so a few months before we can get a shot at it! No data on magnitude and it's a dwarf so it may be very faint.The only clue is that the brightest pixel received 1,900 electrons in 103 seconds, this is in IR but it should be detectable with an IR sensitive camera!

Weird how the paper talks about the planet K2-18b but doesn't explicitly mention the name of its parent star.

Just imagine, there could be someone in a garden on K2-18b (or K2-18c, perhaps?)  pointing a telescope at Earth at the same time, trying to get an image of us :)  Please do wave.

James

[Scooot]

2 hours ago, Stub Mandrel said:

Weird how the paper talks about the planet K2-18b but doesn't explicitly mention the name of its parent star.

I thought that but I did a bit of googling yesterday & I think the star name is just K2-18

http://www.exoplanetkyoto.org/exohtml/K2-18.html

[Stub Mandrel]

2 hours ago, Scooot said:

I thought that but I did a bit of googling yesterday & I think the star name is just K2-18

http://www.exoplanetkyoto.org/exohtml/K2-18.html

It is, as far as I can tell.

[andrew s]

8 minutes ago, Stub Mandrel said:

It is, as far as I can tell.

It is also ucac4 488-054338. It has other catalogue numbers as well use "simbad" to see them.

Red Dwarf M class stars are known for producing very large flares but not all do so let's hope it is one that doesnot. If not any life might get sterilized. 

Regards Andrew 

[andrew s]

Here a paper on the discovery. Even if you don't want the details they are a good example of the work that goes into these observations and their reduction.

https://arxiv.org/abs/1909.04642

This seems to be the key result.  I will need to study the paper to see just how strong the case is.

Regards Andrew

[lukebl]

It's all fascinating and exciting stuff, but we're having a hard enough job determining whether or not there's life elswehere in our own solar system. I doubt very much that we'll have much luck with a planet we can't even see 124 light years away!

Edited September 13, 2019 by lukebl

[andrew s]

14 minutes ago, lukebl said:

It's all fascinating and exciting stuff, but we're having a hard enough job determining whether or not there's life elswehere in our own solar system. I doubt very much that we'll have much luck with a planet we can't even see 124 light years away!

Interestingly they are different challenges! 

In our solar system we are looking for residual or at least very low levels of life.

On other worlds we will be looking for abundant life that is sufficiently active to pull the atmosphere out of chemical equilibrium.  As an example if you see O2 and H2 as persistant gases on a planet then the O2 must be being replenished as other wise it would have reacted to form H2O. Similarly with othe indicators.

A distant observer of earth would see CH4 and O2 which readily react to form H2O and CO2 so the methane CH4 has to be replenished. You then have to find other ways to tell if its life or geochemical replenishment! 

It looks like K2-18b is an unlikely candidate.

Regards Andrew 

Edited September 13, 2019 by andrew s

[m1dlj]

Had the pleasure of chatting to Jayesh Goyal, PhD student in Astrophysics at The University of Exeter UK. He made an excellent presentation to our local astro society, explaining how the team at Exeter are using current Met Office models to try and understand exoplanet atmospheres.

Apparently, Dimethyl Sulphide, CH3-S-CH3 (rotten cabbage), would be one of the best bio markers to look for, but we're going to need the JWST up and running before attempting that.

Ray

(Tiverton & Mid Devon Astronomy Society)