Super-Earth Found in Habitable Zone of Nearby Red Dwarf

[CygnusX-1]

The interview: John Batchelor Show

The scientific paper: https://www.nature.com/nature/journal/v544/n7650/full/nature22055.html[/PLAIN] ]Nature and ArXiv

The basic facts:

Star Name: LHS 1140
Constellation: Cetus the Whale
Distance from Sun: 41 light-years
Star type: Red dwarf (much smaller, cooler, and fainter than Sun)
Mass of Star: 15% of Sun's
Diameter of Star: 19% of Sun's
Luminosity of Star: 0.3% of Sun's
-----------------------------------------------------------
Planet Name: LHS 1140 b
Distance from Star: 8.1 million miles (vs. 36 million miles for Mercury)
Orbital Period: 24.7 days (vs. 88 days for Mercury)
Mass of Planet: 6.6 Earth masses
Diameter of Planet: 1.4 Earth diameters
Density of Planet: 12.5 grams per cubic centimeter (much denser than Earth or any other planet in our solar system)
Composition of Planet: High density implies a world of iron and rock, like Earth.

 

[Zahid Hasan]

It is really pointless but an amazing discovery. When are we planning on going to this "Super-Earth"? It is not realistic, at least not for another millions and millions of years, if even.

 

[mfb]

Do we have to physically go somewhere to make it interesting?

It is not realistic, at least not for another millions and millions of years, if even.

We went from riding on horses to going to the Moon in less than 200 years. Imagine what we might be able to do in 200 more years.

 

[Zahid Hasan]

You are absolutely right, it is good knowledge but that knowledge could be spent elsewhere to fix our current issues, but that's just me.

Riding horses was local and the Moon isn't too far away, but at the rate we are going, I doubt those fast-travelling will be any time soon.

 

[mfb]

Riding horses was the fastest way of transport in 1800.
Going to the Moon was absolutely unthinkable in 1800 - we didn't even know the basic physics necessary to go there. Less than 200 years later we had manned rockets going there.

For interstellar travel, we are in a better position than people in 1800 were for a mission to Moon. We understand the physics that can allow interstellar travel. There might be more efficient ways - who knows.

But I don't think we should make this thread about interstellar travel. It is about the planets discovered.

 

[Zahid Hasan]

True you are absolutely right.

My point was for interstellar travel we are required to do way more research than just going to the moon but your point is also valid for the fact that it may be possible as we don't know what the future holds.

Regardless, I wonder if this planet has any microbial life at the moment.

 

[mfb]

It transits and it is heavy enough for radial velocity measurements. JWST and E-ELT should get nice spectra of its atmosphere in the next 2-10 years, and we will probably get a much better mass estimate from E-ELT as well.

 

[BenAS]

Do we have to physically go somewhere to make it interesting?We went from riding on horses to going to the Moon in less than 200 years. Imagine what we might be able to do in 200 more years.

Who knows, in 200 years we might have telescopes that could map its surface. It's an incredible discovery and I for one am super excited about what we can learn from it. Exoplanet science has improved more in the last 20 years than we expected 20 years ago.

 

[mheslep]

Do we have to physically go somewhere to make it interesting?

But is it interesting? Is this particular hot rock orbiting 8 million miles from a distant star interesting? A corollary to the growing list of 'transit' discoveries among the 100 million stars of this Galaxy is that they are not all interesting.

It transits and it is heavy enough for radial velocity measurements. JWST and E-ELT should get nice spectra of its atmosphere in the next 2-10 years, and we will probably get a much better mass estimate from E-ELT as well.

Is a significant atmosphere possible at 13 million km from a star?

 

[stefan r]

Is a significant atmosphere possible at 13 million km from a star?

Of course. It has higher gravity than earth. For all we know it could be accreting more atmosphere. The flow of gasses are still being studied in our solar system.

 

[mfb]

But is it interesting? Is this particular hot rock orbiting 8 million miles from a distant star interesting? A corollary to the growing list of 'transit' discoveries among the 100 million stars of this Galaxy is that they are not all interesting.

It is not a hot rock. It is in the habitable zone - closer to the star than Earth, but the star is less luminous than the Sun. As it is larger than Earth and orbiting a quiet star, it is quite likely that it has an atmosphere. It is a very good candidate for liquid water on the surface, and we can probably test this within 10 years.

 

[stefan r]

It is not a hot rock. It is in the habitable zone - closer to the star than Earth, but the star is less luminous than the Sun. As it is larger than Earth and orbiting a quiet star, it is quite likely that it has an atmosphere. It is a very good candidate for liquid water on the surface, and we can probably test this within 10 years.

Earth is still hot. A larger planet should take longer to cool off. If it is rotating it should have some tidal heating too.

 

[mfb]

Well, the interior will be hot, sure. The surface can have a nice temperature.