‘Odds in favour’ of finding other young Earth-like planets in young stellar groups

‘Odds in favour’ of finding other young Earth-like planets after scientists find more Sun-like stars in young stellar groups than expected

  • Researchers studied groups of young stars known as ‘young moving groups’
  • It had previously been difficult to study these as the blend into the Milky Way
  • As a result the team found that they contain more stars than previously thought
  • These systems may also contain young, hot and rocky proto-Earth-like planets
  • It should be possible to spot their magma oceans with infrared telescopes

The ‘odds are in favour’ of finding other young Earth-like planets, as experts have found that young stellar groups contain more Sun-like stars than expected.

Experts from Sheffield studied groups of young stars in the Milky way to determine if they were typical when compared to other star forming regions in the universe.

They then investigated whether the number of various stars in each group increased the chances of finding ‘magma ocean planets’ — which are like ‘baby’ Earths.

The findings may help scientists understand if star formation is a universal phenomenon — alongside shedding light on how rocky, Earth-like worlds form.

The ‘odds are in favour’ of finding other young Earth-like planets, as experts have found that young stellar groups contain more Sun-like stars than expected. Pictured, an artist’s impression of a so-called ‘magma ocean planet’ forming like the young Earth did

Magma ocean planets are formed by the successive collision of rocks and smaller planetoids, the impacts of which heat up their surface so much that it becomes molten rock — helping us to find them.

‘These magma ocean planets are easier to detect near stars like the Sun, which are twice as heavy as the average mass star.’ said paper author and astrophysicist Richard Parker of the University of Sheffield.

‘These planets emit so much heat that we will be able to observe the glow from them using the next generation of infra-red telescopes.’

‘The locations where we would find these planets are so-called “young moving groups” which are groups of young stars that are less than 100 million years old — which is young for a star,’ Dr Parker explained.

‘However, they typically only contain a few tens of stars each and previously it was difficult to determine whether we had found all of the stars in each group because they blend into the background of the Milky Way galaxy.’

‘Observations from the Gaia telescope have helped us to find many more stars in these groups, which enabled us to carry out this study.’

Experts from Sheffield studied groups of young stars in the Milky way to determine if they were typical when compared to other star forming regions in the universe. They then investigated whether the number of stars in each group increased the chances of finding so-called 'magma ocean planets', pictured — which are like 'baby' Earths

Experts from Sheffield studied groups of young stars in the Milky way to determine if they were typical when compared to other star forming regions in the universe. They then investigated whether the number of stars in each group increased the chances of finding so-called ‘magma ocean planets’, pictured — which are like ‘baby’ Earths

The findings come after scientists at the Max Planck Institute spotted an Earth-like planet orbiting Kepler-160 — a star which resembles our own sun in both size and its surface temperature.

The planet, KOI-456.04, is located in the system’s so-called ‘habitable zone’ — the region around a star in which liquid water could exist on a planet’s surface.

However, with Kepler-160 and the planet both being some 3,000 light-years away, it remains unclear what KOI-456.04’s atmosphere might be like.

'The locations where we would find these planets are so-called "young moving groups" which are groups of young stars that are less than 100 million years old — which is young for a star,' Dr Parker explained. 'Observations from the Gaia telescope [pictured] have helped us to find many more stars in these groups, which enabled us to carry out this study'

‘The locations where we would find these planets are so-called “young moving groups” which are groups of young stars that are less than 100 million years old — which is young for a star,’ Dr Parker explained. ‘Observations from the Gaia telescope [pictured] have helped us to find many more stars in these groups, which enabled us to carry out this study’

‘Being involved in this project was one of the highlights of our university experience,’ said undergraduate researcher Molly Haigh, also of the University of Sheffield.

‘It was rewarding to see a physical application of the computer coding we learnt in our degree by sampling the initial mass distribution of stars and how this can relate to the future of exoplanet detection.’

With their initial study complete, the researchers are now looking to use computer simulations to map out the origin of the young groups of stars they examined. 

The full findings of the study were published in the Astrophysical Journal.

WHAT IS THE EUROPEAN SPACE AGENCY’S GAIA PROBE AND WHAT IS DESIGNED TO DO?

Gaia is an ambitious mission to chart a three-dimensional map of our galaxy, the Milky Way, and in the process reveal its composition, formation and evolution.

Gaia has been circling the sun nearly a million miles beyond Earth’s orbit since its launch by the European Space Agency (ESA) in December 2013. 

On its journey, the probe has been discreetly snapping pictures of the Milky Way, identifying stars from smaller galaxies long ago swallowed up by our own.

Tens of thousands of previously undetected objects are expected to be discovered by Gaia, including asteroids that may one day threaten Earth, planets circling nearby stars, and exploding supernovas. 

Artist's impression of Gaia mapping the stars of the Milky Way. Gaia's mapping effort is already unprecedented in scale, but it still has several years left to run. Gaia maps the position of the Milky Way's stars in a couple of ways. It pinpoints the location of the stars but the probe can also plot their movement, by scanning each star about 70 times

Artist’s impression of Gaia mapping the stars of the Milky Way. Gaia maps the position of the Milky Way’s stars in a couple of ways. It pinpoints the location of the stars but the probe can also plot their movement, by scanning each star about 70 times

Astrophysicists also hope to learn more about the distribution of dark matter, the invisible substance thought to hold the observable universe together.

They also plan to test Albert Einstein’s general theory of relativity by watching how light is deflected by the sun and its planets.

The satellite’s billion-pixel camera, the largest ever in space, is so powerful it would be able to gauge the diameter of a human hair at a distance of 621 miles (1,000 km).

This means nearby stars have been located with unprecedented accuracy.

Gaia maps the position of the Milky Way’s stars in a couple of ways.

Gaia’s all-sky view of our Milky Way Galaxy and neighbouring galaxies, based on measurements of nearly 1.7 billion stars. The map shows the total brightness and colour of stars observed by the ESA satellite in each portion of the sky between July 2014 and May 2016. Brighter regions indicate denser concentrations of especially bright stars, while darker regions correspond to patches of the sky where fewer bright stars are observed. The colour representation is obtained by combining the total amount of light with the amount of blue and red light recorded by Gaia in each patch of the sky.

Gaia’s all-sky view of our Milky Way Galaxy and neighbouring galaxies, based on measurements of nearly 1.7 billion stars. The map shows the total brightness and colour of stars observed by the ESA satellite in each portion of the sky between July 2014 and May 2016. Brighter regions indicate denser concentrations of especially bright stars, while darker regions correspond to patches of the sky where fewer bright stars are observed. The colour representation is obtained by combining the total amount of light with the amount of blue and red light recorded by Gaia in each patch of the sky.

It pinpoints the location of the stars but the probe can also plot their movement, by scanning each star about 70 times.

This is what allows scientists to calculate the distance between Earth and each star, which is a crucial measure.

In September 2016, ESA released the first batch of data collected by Gaia, which included information on the brightness and position of over a billion stars.

In April 2018, this was expanded to high-precision measurements of almost 1.7 billion stars.