Nav: Home

Massive collision in the planetary system Kepler 107

February 06, 2019

Since, in 1995 the first extrasolar planet was discovered almost 4,000 planets have been found around the nearest stars. This allows us to study a large variety of configurations for these planetary systems. The evolution of the planets orbiting other stars can be affected, mainly, by two phenomena: the evaporation of the upper layers of the planet due to the effect of the X-rays and ultraviolet emitted by the central star, and by the impacts of other celestial bodies of the size of a planet.

The former effect has been observed a number of times in extrasolar systems, but until now there have been no proof of the existence of major impacts, as has apparently occurred in the Kepler 107 system.

The central star, Kepler 107, is a bit bigger than the Sun, and has four planets rotating around it; it was the two innermost planets which drew the interest of the astrophysicists. Using data from NASA's Kepler satellite and from the National Galileo Telescope (TNG) at the Roque de los Muchachos Observatory (Garafía, La Palma, Canary Islands), the team determined the parameters of the star, and measured the radii and masses of these planets. Although the innermost two have similar radii their masses are very different. In fact the second is three times denser than the first.

The extraordinarily high density of the planet Kepler 107c is more than double that of the Earth. This exceptional density for a planet has intrigued researchers, and suggests that its metallic core, its densest part, is anomalously big for a planet.

This would be still considered normal if it were not for the prediction that photo-evaporation causes the densest planet in a system to be the nearest to its star. To explain how it is possible that, in this case, the nearest has only half the density of the second, the hypothesis was proposed that the planet Kepler 107c was formed as the result of a major impact. This impact must have ripped away its outer layers, thus leaving the central core as a much bigger fraction than before. After tests carried out via simulations, this hypothesis seems to be the most likely.

This study will allow us to better understand the formation and evolution of exoplanets. Specifically it picks out the importance of the relationship between stellar physics and exoplanetary research. "We need to know the star to better understand the planets which are in orbit around it" says Savita Mathur, a researcher at the IAC in Tenerife, and one of the authors of the article. "In this study we made a seismic analysis to estimate the parameters of the star which hosts the planet. Asteroseismology is playing a key role in the field of the exoplanets, because it has been shown that it is one of the best methods for a precise characterization of the stars". That is why during the past decade it has become one of the main methods for characterizing stars, and it will remain so in the coming years, thanks to the space missions for discovering exoplanets: TESS (NASA) and PLATO (ESA).
-end-


Instituto de Astrofísica de Canarias (IAC)

Related Evolution Articles:

Artificial evolution of an industry
A research team has taken a deep dive into the newly emerging domain of 'forward-looking' business strategies that show firms have far more ability to actively influence the future of their markets than once thought.
Paleontology: Experiments in evolution
A new find from Patagonia sheds light on the evolution of large predatory dinosaurs.
A window into evolution
The C4 cycle supercharges photosynthesis and evolved independently more than 62 times.
Is evolution predictable?
An international team of scientists working with Heliconius butterflies at the Smithsonian Tropical Research Institute (STRI) in Panama was faced with a mystery: how do pairs of unrelated butterflies from Peru to Costa Rica evolve nearly the same wing-color patterns over and over again?
Predicting evolution
A new method of 're-barcoding' DNA allows scientists to track rapid evolution in yeast.
Insect evolution: Insect evolution
Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich have shown that the incidence of midge and fly larvae in amber is far higher than previously thought.
Evolution of aesthetic dentistry
One of the main goals of dental treatment is to mimic teeth and design smiles in the most natural and aesthetic manner, based on the individual and specific needs of the patient.
An evolution in the understanding of evolution
In an open-source research paper, a UVA Engineering professor and her former Ph.D. student share a new, more accurate method for modeling evolutionary change.
Chemical evolution -- One-pot wonder
Before life, there was RNA: Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich show how the four different letters of this genetic alphabet could be created from simple precursor molecules on early Earth -- under the same environmental conditions.
Catching evolution in the act
Researchers have produced some of the first evidence that shows that artificial selection and natural selection act on the same genes, a hypothesis predicted by Charles Darwin in 1859.
More Evolution News and Evolution Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Teaching For Better Humans 2.0
More than test scores or good grades–what do kids need for the future? This hour, TED speakers explore how to help children grow into better humans, both during and after this time of crisis. Guests include educators Richard Culatta and Liz Kleinrock, psychologist Thomas Curran, and writer Jacqueline Woodson.
Now Playing: Science for the People

#556 The Power of Friendship
It's 2020 and times are tough. Maybe some of us are learning about social distancing the hard way. Maybe we just are all a little anxious. No matter what, we could probably use a friend. But what is a friend, exactly? And why do we need them so much? This week host Bethany Brookshire speaks with Lydia Denworth, author of the new book "Friendship: The Evolution, Biology, and Extraordinary Power of Life's Fundamental Bond". This episode is hosted by Bethany Brookshire, science writer from Science News.
Now Playing: Radiolab

Space
One of the most consistent questions we get at the show is from parents who want to know which episodes are kid-friendly and which aren't. So today, we're releasing a separate feed, Radiolab for Kids. To kick it off, we're rerunning an all-time favorite episode: Space. In the 60's, space exploration was an American obsession. This hour, we chart the path from romance to increasing cynicism. We begin with Ann Druyan, widow of Carl Sagan, with a story about the Voyager expedition, true love, and a golden record that travels through space. And astrophysicist Neil de Grasse Tyson explains the Coepernican Principle, and just how insignificant we are. Support Radiolab today at Radiolab.org/donate.