Two super-Earths around star K2-18

[Natural Citizen]

We should go take their oil.

 

[xyz]

Two super-Earths around star K2-18
December 5, 2017

New research using data collected by the European Southern Observatory (ESO) has revealed that a little-known exoplanet called K2-18b could well be a scaled-up version of Earth.

Just as exciting, the same researchers also discovered for the first time that the planet has a neighbor.

"Being able to measure the mass and density of K2-18b was tremendous, but to discover a new exoplanet was lucky and equally exciting," says lead author Ryan Cloutier, a PhD student in U of T Scarborough's Centre for Planet Science, U of T's Department of Astronomy and Astrophysics, and Université de Montréal Institute for research on exoplanets (iREx).

Both planets orbit K2-18, a red-dwarf star located about 111 light years away in the constellation Leo. When the planet K2-18b was first discovered in 2015, it was found to be orbiting within the star's habitable zone, making it an ideal candidate to have liquid surface water, a key element in harbouring conditions for life as we know it.

The data set used by the researchers came from the High Accuracy Radial Velocity Planet Searcher (HARPS) using the ESO's 3.6m telescope at La Silla Observatory, in Chile. HARPS allows for measurements of radial velocities of stars, which are affected by the presence of planets, to be taken with the highest accuracy currently available. Hence, this instrument allows for the detection of very small planets around them.

In order to figure out whether K2-18b was a scaled-up version of Earth (mostly rock), or a scaled-down version of Neptune (mostly gas), researchers had to first figure out the planet's mass, using radial velocity measurements taken with HARPS.

"If you can get the mass and radius, you can measure the bulk density of the planet and that can tell you what the bulk of the planet is made of," says Cloutier.
After using a machine-learning approach to figure out the mass measurement, Cloutier and his team were able to determine the planet is either a mostly rocky planet with a small gaseous atmosphere – like Earth, but bigger – or a mostly water planet with a thick layer of ice on top of it.

"With the current data, we can't distinguish between those two possibilities," he says. "But with the James Webb Space Telescope (JWST) we can probe the atmosphere and see whether it has an extensive atmosphere or it's a planet covered in water."

Read more at: https://phys.org/new...ar-k2-.html#jCp

There's so many choices!!! Can't wait until the james web is up in running!

So one year is 33 days? Would there be more extreme temperature changes?

 

[anotherlife]

Wouldn't a scaled up earth have a much stronger gravity?

Yes, so you will have more muscles as it would exercise you continuously. Then you visit old Earth and the chicks will all dig you.

 

[BasicHumanUnit]

Congrats!

This is the first post of yours of value.

Hard to believe they can get ANY info on such an incredibly microscopic subject.

It'd be easier to identify a single grain of sand on a beach on the opposite coast of the USA with binoculars than what they're doing.
(figuratively speaking)

Can't imagine only Earth could have harbored life. If that is in fact the case.....there MUST be a God.
Once we actually find alien beings, the whole Bible concept has a bit of a credibility issue.

The New, NEW, "Cosmic" Testament ??

 

[BasicHumanUnit]

Yes, so you will have more muscles as it would exercise you continuously. Then you visit old Earth and the chicks will all dig you.

but.....because of the extra gravity, those muscles would be offset by drooping eyes, sagging skin, dangling earlobes and other not so pretty effects.....plus, guys would have the "Bad Grampa" problem (lol).....so much for the chicks

 

[ScienceRocks]

Two super-Earths around star K2-18
December 5, 2017

New research using data collected by the European Southern Observatory (ESO) has revealed that a little-known exoplanet called K2-18b could well be a scaled-up version of Earth.

Just as exciting, the same researchers also discovered for the first time that the planet has a neighbor.

"Being able to measure the mass and density of K2-18b was tremendous, but to discover a new exoplanet was lucky and equally exciting," says lead author Ryan Cloutier, a PhD student in U of T Scarborough's Centre for Planet Science, U of T's Department of Astronomy and Astrophysics, and Université de Montréal Institute for research on exoplanets (iREx).

Both planets orbit K2-18, a red-dwarf star located about 111 light years away in the constellation Leo. When the planet K2-18b was first discovered in 2015, it was found to be orbiting within the star's habitable zone, making it an ideal candidate to have liquid surface water, a key element in harbouring conditions for life as we know it.

The data set used by the researchers came from the High Accuracy Radial Velocity Planet Searcher (HARPS) using the ESO's 3.6m telescope at La Silla Observatory, in Chile. HARPS allows for measurements of radial velocities of stars, which are affected by the presence of planets, to be taken with the highest accuracy currently available. Hence, this instrument allows for the detection of very small planets around them.

In order to figure out whether K2-18b was a scaled-up version of Earth (mostly rock), or a scaled-down version of Neptune (mostly gas), researchers had to first figure out the planet's mass, using radial velocity measurements taken with HARPS.

"If you can get the mass and radius, you can measure the bulk density of the planet and that can tell you what the bulk of the planet is made of," says Cloutier.
After using a machine-learning approach to figure out the mass measurement, Cloutier and his team were able to determine the planet is either a mostly rocky planet with a small gaseous atmosphere – like Earth, but bigger – or a mostly water planet with a thick layer of ice on top of it.

"With the current data, we can't distinguish between those two possibilities," he says. "But with the James Webb Space Telescope (JWST) we can probe the atmosphere and see whether it has an extensive atmosphere or it's a planet covered in water."

Read more at: https://phys.org/new...ar-k2-.html#jCp

There's so many choices!!! Can't wait until the james web is up in running!

So one year is 33 days? Would there be more extreme temperature changes?

Depends on the Eccentricity of its orbit around its star. If it is more round there shouldn't be much difference in temperature but if it is more oval with one portion of the year sweaping closer to its star that is a different story.

This is a much smaller star so 33 days is within the habital zone.

 

[CarlinAnnArbor]

Wouldn't a scaled up earth have a much stronger gravity?

Depends on the mass.

 

[CarlinAnnArbor]

If viewed with our technology; from any of these locations considered "possibly habitable"... Venus would look earth like, and fools would get excited... There is a lot more to consider before considering any planet earth like. I'd be willing to bet that out all that have been found; not a single one, could be readily habitable by humans.

The "science" worshippers place a lot of value on their faith.

 

[WillMunny]

If viewed with our technology; from any of these locations considered "possibly habitable"... Venus would look earth like, and fools would get excited... There is a lot more to consider before considering any planet earth like. I'd be willing to bet that out all that have been found; not a single one, could be readily habitable by humans.

But the point is, we don't know enough details about these Earth-sized alien planets to be sure of that one way or another. For all we know it could be the opposite, there may be a dozen Earths for every Venus. Since water is the most common simple compound in the universe, if a planet has conditions for liquid water to exist, carbon-based life can exist and thrive. Our own planet is proof of this. If it happened here it must have happened elsewhere.

 

[WillMunny]

If there is complex, alien life on any other planet, it's extremely likely to be carbon-based like Earth's. Simply because carbon is the atomic element that does the best, easiest job of forming extremely complex molecules with hydrogen, oxygen & nitrogen. Which makes up the proteins and DNA of every particle of life on this planet. LOL, I'll bet those chest-bursting, acid-blood aliens from those Sigourney Weaver movies are probably carbon-based as well.

 

[WillMunny]

By the way, Matty, I honestly applaud you for making such an interesting, thoughtful thread. I didn't know you had it in ya, my son!

 

[Old Rocks]

Wouldn't a scaled up earth have a much stronger gravity?

Yes, so life there would adapt by being built smaller and closer to the ground. A non-obese human could probably live on one but it would be an exhausting 24/7 workout.

Yes, people could adapt, especially with the aid of technology. But no crops or livestock would be able to survive. Which means all food would have to be transported in from great distances.

Yes, but I was automatically assuming there would be native planets/animals on that planet that are safe for humans to eat. If the planet's other conditons were similar to earth, small, light Earth animals could adapt because they wouldn't notice that much difference in weight. As for humans, let's say the planet's gravity was 50% higher than Earth's: I'm a human telephone-pole in the early 140s pounds. So if I suddenly weighed 210 pounds, I'd survive but I'd be easily fatigued and not able to move around that much for that long without getting burnt-out. An elephant or whale or Rosie O'Donnell? No way.

Wrong on the whale. It feels little gravity unless grounded out of water.

 

[Old Rocks]

If there is complex, alien life on any other planet, it's extremely likely to be carbon-based like Earth's. Simply because carbon is the atomic element that does the best, easiest job of forming extremely complex molecules with hydrogen, oxygen & nitrogen. Which makes up the proteins and DNA of every particle of life on this planet. LOL, I'll bet those chest-bursting, acid-blood aliens from those Sigourney Weaver movies are probably carbon-based as well.

I think you are correct on the carbon based life. However, I wonder about the compatability of earth life with an alien planets life. Allergies. Proteans that we have never ran into before.

 

[CarlinAnnArbor]

If it happened here it must have happened elsewhere

And there's that leap of faith I mentioned.

 

[ScienceRocks]

A Second Super-Earth for K2-18
by Paul Gilster on December 7, 2017

The transiting red dwarf K2-18 is about 111 light years out in the general direction of the constellation Leo, with a mass of 40 percent of Sol’s. A super-Earth, K2-18b, was detected here in 2015 through light curve analysis of data from the reconfigured Kepler K2 mission, and we now have the first measurement of the planet’s mass, drawing on radial velocity data from HARPS. The two planet detection methods in conjunction thus firm up our knowledge of a possible habitable zone planet.

But they also reveal, in the analysis of Ryan Cloutier (University of Toronto) and colleagues, a second super-Earth, K2-18c, which turns out to be non-transiting, and therefore non-coplanar with K2-18b. As we saw yesterday, HARPS (High Accuracy Radial Velocity Planet Searcher), is capable of drilling down to about one meter per second in the analysis of the stellar wobbles that radial velocity methods examine. The current data set gives us another interesting world while reminding us of the capabilities of the ESPRESSO spectrograph I talked about yesterday.

Image: An artist’s conception of planet K2-18b, its star K2-18 and the second planet K2-18c. Credit: Alex Boersma (www.alexboersma.com). Two things I like about this image: Its evocative feel, an imaginative take on a world whose actual conditions are speculative, and the fact that the artist is given credit by the Université de Montréal Institute for research on exoplanets (iREx). Artists should always get credit but all too often do not in press materials.

When it came to K2-18b, the challenge was to figure out whether the planet was a gaseous mini-Neptune or a predominately rocky world. Hence the importance of the radial velocity measurements, giving us in combination with earlier transit data a tentative mass as well as a radius, allowing the planet’s density to be inferred. The researchers believe K2-18b is either a large, rocky planet with a small gaseous atmosphere or a water planet with an ice crust. The range is explained by the uncertainty in the measured mass, which the paper cites at 24%.

It’s interesting to note that this planet’s mass is close to that of another possible habitable zone planet, LHS 1140b, though the dissimilarities are also striking:

K2-18b is of a similar mass to the habitable zone planet LHS 1140b (Dittmann et al. 2017) and receives a comparable level of insolation despite being ∼ 1.6 times larger than LHS 1140b. Analyzing the mass-radius relationship of these small planets over a range of equilibrium temperatures is a critical step towards understanding which of these systems have retained significant atmospheric content thus making them more suitable to extraterrestrial life.

Given the inability to distinguish between the two outcomes, we have to look to future instruments, like the upcoming James Webb Space Telescope. Cloutier points out that JWST should be able to probe the atmosphere of K2-18b to make the call. We keep bumping up against this ceiling as we wait for new instruments to come online. A nearby transiting world, this planet should climb toward the top of the target list for atmospheric analysis. K2-18 is now the second brightest M dwarf with a transiting habitable zone planet behind LHS 1140.

On JWST, by the way, be sure to read the always reliable Lee Billings’ article What Will NASA’s Biggest-Ever Space Telescope Study First? for a look at the inevitable prioritization of observing time and also the potential of the space telescope. A quick bit from the essay:

Unlike Kepler, which simply surveyed a single star-packed field of view for transits, Webb can zoom in on individual transiting worlds for deeper study. Astronomers should be able to use it to detect water vapor, methane, carbon dioxide and other gases in some silhouetted planets’ upper atmospheres by monitoring the starlight streaming through. They could also record a planet’s passage in front of and then behind its star, using the difference between the two observations to crudely measure a world’s temperature, weather patterns and clouds. “Webb is going to be great for exoplanets,” says Kepler project scientist Natalie Batalha, an astronomer at NASA Ames Research Center who leads the most time-intensive ERS program, which will use nearly 80 hours of Webb’s time to study transiting worlds. “It’s just that this is a difficult game to play, because the signals we’re looking for are really tiny. Seen [in transit] from another star, Venus blocks one part per ten-thousandth of the sun’s light, and its atmosphere intercepts one two-hundredth of that. It’s tough to see—you need a big mirror and great instrumentation to do it.”

As to newly detected K2-18c, the researchers looked for but did not find significant transit timing variations (TTV) in the K2 data. The Cloutier paper continues:

The orbit of the newly discovered K2-18c lies interior to that of K2-18b and yet the planet is non-transiting. This implies that the orbital planes of the planets are mutually inclined. In order for K2-18c to not be seen in-transit the planetary system requires a mutual inclination of just ≿ 1.4° which is consistent with the observed distribution of mutually inclined multi-planet systems (Figueira et al. 2012; Fabrycky et al. 2014).

The team’s dynamical simulations show that the oscillation timescale of the planets’ orbital inclinations is in the range of 106 years, meaning that it may be a long time before K2-18c can be seen in a transit from Earth. And the authors believe that finding the second planet through radial velocity data emphasizes the prevalence of Earth- to super-Earth size planets in M-dwarf systems, with multi-planet systems offering potential insights into planet formation processes around M-dwarfs. Comparative planetology here we come.

The paper is Cloutier et al., “Characterization of the K2-18 multi-planetary system with HARPS: A habitable zone super-Earth and discovery of a second, warm super-Earth on a non-coplanar orbit,” submitted to Astronomy & Astrophysics (preprint).

 

[Fort Fun Indiana]

But no crops or livestock would be able to survive.

*without genetic modification, sir

 

[Fort Fun Indiana]

And there's that leap of faith I mentioned.

That's not a leap of faith, it's an evidence-based determination.

 

[sealybobo]

Two super-Earths around star K2-18
December 5, 2017

New research using data collected by the European Southern Observatory (ESO) has revealed that a little-known exoplanet called K2-18b could well be a scaled-up version of Earth.

Just as exciting, the same researchers also discovered for the first time that the planet has a neighbor.

"Being able to measure the mass and density of K2-18b was tremendous, but to discover a new exoplanet was lucky and equally exciting," says lead author Ryan Cloutier, a PhD student in U of T Scarborough's Centre for Planet Science, U of T's Department of Astronomy and Astrophysics, and Université de Montréal Institute for research on exoplanets (iREx).

Both planets orbit K2-18, a red-dwarf star located about 111 light years away in the constellation Leo. When the planet K2-18b was first discovered in 2015, it was found to be orbiting within the star's habitable zone, making it an ideal candidate to have liquid surface water, a key element in harbouring conditions for life as we know it.

The data set used by the researchers came from the High Accuracy Radial Velocity Planet Searcher (HARPS) using the ESO's 3.6m telescope at La Silla Observatory, in Chile. HARPS allows for measurements of radial velocities of stars, which are affected by the presence of planets, to be taken with the highest accuracy currently available. Hence, this instrument allows for the detection of very small planets around them.

In order to figure out whether K2-18b was a scaled-up version of Earth (mostly rock), or a scaled-down version of Neptune (mostly gas), researchers had to first figure out the planet's mass, using radial velocity measurements taken with HARPS.

"If you can get the mass and radius, you can measure the bulk density of the planet and that can tell you what the bulk of the planet is made of," says Cloutier.
After using a machine-learning approach to figure out the mass measurement, Cloutier and his team were able to determine the planet is either a mostly rocky planet with a small gaseous atmosphere – like Earth, but bigger – or a mostly water planet with a thick layer of ice on top of it.

"With the current data, we can't distinguish between those two possibilities," he says. "But with the James Webb Space Telescope (JWST) we can probe the atmosphere and see whether it has an extensive atmosphere or it's a planet covered in water."

Read more at: https://phys.org/new...ar-k2-.html#jCp

There's so many choices!!! Can't wait until the james web is up in running!

I just got cable. Any science shows you recommend I tape and watch?

 

[sealybobo]

Two super-Earths around star K2-18
December 5, 2017

New research using data collected by the European Southern Observatory (ESO) has revealed that a little-known exoplanet called K2-18b could well be a scaled-up version of Earth.

Just as exciting, the same researchers also discovered for the first time that the planet has a neighbor.

"Being able to measure the mass and density of K2-18b was tremendous, but to discover a new exoplanet was lucky and equally exciting," says lead author Ryan Cloutier, a PhD student in U of T Scarborough's Centre for Planet Science, U of T's Department of Astronomy and Astrophysics, and Université de Montréal Institute for research on exoplanets (iREx).

Both planets orbit K2-18, a red-dwarf star located about 111 light years away in the constellation Leo. When the planet K2-18b was first discovered in 2015, it was found to be orbiting within the star's habitable zone, making it an ideal candidate to have liquid surface water, a key element in harbouring conditions for life as we know it.

The data set used by the researchers came from the High Accuracy Radial Velocity Planet Searcher (HARPS) using the ESO's 3.6m telescope at La Silla Observatory, in Chile. HARPS allows for measurements of radial velocities of stars, which are affected by the presence of planets, to be taken with the highest accuracy currently available. Hence, this instrument allows for the detection of very small planets around them.

In order to figure out whether K2-18b was a scaled-up version of Earth (mostly rock), or a scaled-down version of Neptune (mostly gas), researchers had to first figure out the planet's mass, using radial velocity measurements taken with HARPS.

"If you can get the mass and radius, you can measure the bulk density of the planet and that can tell you what the bulk of the planet is made of," says Cloutier.
After using a machine-learning approach to figure out the mass measurement, Cloutier and his team were able to determine the planet is either a mostly rocky planet with a small gaseous atmosphere – like Earth, but bigger – or a mostly water planet with a thick layer of ice on top of it.

"With the current data, we can't distinguish between those two possibilities," he says. "But with the James Webb Space Telescope (JWST) we can probe the atmosphere and see whether it has an extensive atmosphere or it's a planet covered in water."

Read more at: https://phys.org/new...ar-k2-.html#jCp

There's so many choices!!! Can't wait until the james web is up in running!

The other day a guy on usmb was suggesting that it’s unlikely another planet has intelligent life because look at all the things that had to happen for humans to exist. We are the only intelligent life on this planet. A lot of things had to happen for us to happen.

And that’s true. What he doesn’t realize is that intelligent life could exist elsewhere and look nothing like us.

I also think dolphins are plenty intelligent.