Nav: Home

The rare molecule weighing in on the birth of planets

September 12, 2019

Astronomers using one of the most advanced radio telescopes have discovered a rare molecule in the dust and gas disc around a young star - and it may provide an answer to one of the conundrums facing astronomers.

The star, named HD 163296, is located 330 light years from Earth and formed over the last six million years.

It is surrounded by a disc of dust and gas - a so-called protoplanetary disc. It is within these discs that young planets are born. Using a radio telescope in the Atacama Desert in Chile, researchers were able to detect an extremely faint signal showing the existence of a rare form of carbon monoxide - known as an isotopologue (13C17O).

The detection has allowed an international collaboration of scientists, led by the University of Leeds, to measure the mass of the gas in the disc more accurately than ever before. The results show that disc is much heavier - or more 'massive' - than previously thought.

Alice Booth, a PhD researcher at Leeds who led the study, said: "Our new observations showed there was between two and six times more mass hiding in the disc than previous observations could measure.

"This is an important finding in terms of the birth of planetary systems in discs - if they contain more gas, then they have more building material to form more massive planets."

The study - The first detection of 13C17O in a protoplanetary disk: a robust tracer of disk gas mass - is published today (12/09/2019) in Astrophysical Journal Letters.

The scientists' conclusions are well timed. Recent observations of protoplanetary discs have perplexed astronomers because they did not seem to contain enough gas and dust to create the planets observed.

Dr John Ilee, a researcher at Leeds who was also involved in the study, added: "The disc-exoplanet mass discrepancy raises serious questions about how and when planets are formed. However, if other discs are hiding similar amounts of mass as HD 163296, then we may just have underestimated their masses until now."

"We can measure disc masses by looking at how much light is given off by molecules like carbon monoxide. If the discs are sufficiently dense, then they can block the light given off by more common forms of carbon monoxide - and that could result in scientists underestimating the mass of the gas present.

"This study has used a technique to observe the much rarer 13C17O molecule - and that's allowed us to peer deep inside the disc and find a previously hidden reservoir of gas."

The researchers made use of one of the most sophisticated radio telescopes in the world - the Atacama Large Millimetre/submillimetre Array (ALMA) - high in the Atacama Desert.

ALMA is able to observe light that is invisible to the naked eye, allowing astronomers to view what is known as the 'cold universe' - those parts of space not visible using optical telescopes.

Booth said: "Our work shows the amazing contribution that ALMA is making to our understanding of the Universe. It is helping build a more accurate picture of the physics leading to the formation of new planets. This of course then helps us understand how the Solar System and Earth came to be."

The researchers are already planning the next steps in their work.

Booth added: "We suspect that ALMA will allow us to observe this rare form of CO in many other discs. By doing that, we can more accurately measure their mass, and determine whether scientists have systematically been underestimating how much matter they contain."
-end-
Notes to editors

For further information, please contact David Lewis in the University of Leeds press office: pressoffice@leeds.ac.uk

University of Leeds

Related Planets Articles:

The rare molecule weighing in on the birth of planets
Astronomers using one of the most advanced radio telescopes have discovered a rare molecule in the dust and gas disc around a young star -- and it may provide an answer to one of the conundrums facing astronomers.
How many Earth-like planets are around sun-like stars?
A new study provides the most accurate estimate of the frequency that planets that are similar to Earth in size and in distance from their host star occur around stars similar to our Sun.
Dead planets can 'broadcast' for up to a billion years
Astronomers are planning to hunt for cores of exoplanets around white dwarf stars by 'tuning in' to the radio waves that they emit.
The sun follows the rhythm of the planets
One of the big questions in solar physics is why the sun's activity follows a regular cycle of 11 years.
Five planets revealed after 20 years of observation
To confirm the presence of a planet, it is necessary to wait until it has made one or more revolutions around its star.
Icy giant planets in the laboratory
Giant planets like Neptune may contain much less free hydrogen than previously assumed.
New NASA mission could find more than 1,000 planets
A NASA telescope that will give humans the largest, deepest, clearest picture of the universe since the Hubble Space Telescope could find as many as 1,400 new planets outside Earth's solar system, new research suggests.
Giant planets around young star raise questions about how planets form
Researchers have identified a young star with four Jupiter and Saturn-sized planets in orbit around it, the first time that so many massive planets have been detected in such a young system.
The stuff that planets are made of
UZH researchers have analyzed the composition and structure of faraway exoplanets using statistical tools.
Largest haul of extrasolar planets for Japan
Forty-four planets in solar systems beyond our own have been unveiled in one go, dwarfing the usual number of confirmations from extrasolar surveys, which is typically a dozen or less.
More Planets News and Planets Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Risk
Why do we revere risk-takers, even when their actions terrify us? Why are some better at taking risks than others? This hour, TED speakers explore the alluring, dangerous, and calculated sides of risk. Guests include professional rock climber Alex Honnold, economist Mariana Mazzucato, psychology researcher Kashfia Rahman, structural engineer and bridge designer Ian Firth, and risk intelligence expert Dylan Evans.
Now Playing: Science for the People

#540 Specialize? Or Generalize?
Ever been called a "jack of all trades, master of none"? The world loves to elevate specialists, people who drill deep into a single topic. Those people are great. But there's a place for generalists too, argues David Epstein. Jacks of all trades are often more successful than specialists. And he's got science to back it up. We talk with Epstein about his latest book, "Range: Why Generalists Triumph in a Specialized World".
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.