Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Discovery of a cool super-Earth

15.11.2018

Our stellar neighbourhood expands

Astronomers from the Observatory of the University of Hamburg were involved in the discovery of a new planet. As part of an international research team led by the Institut de Ciències de l'Espai (ICE, CSIC), they have found a planet in orbit of Barnard's star.


Artistic illustration of a sunset on Barnard's star b

ESO/Martin Kornmesser

Barnard's star is a so-called red dwarf and after the Alpha-Centauri triple stellar system the second closest star to the Sun. As scientists reported in the current issue of Nature, they used astronomical observational data from about 20 years ago and combined it with new measurement data taken with the CARMENES planet-hunter spectrograph at Calar Alto/Spain among others.

The astronomers found significant evidence for a super-Earth with the size of 3.2 Earth masses, orbiting the red dwarf every 233 days. The new planet is at the so-called snowline of the star and is likely to be a frozen world.

Barnard's star is only six light-years from us and its velocity on Earth's night sky is the fastest of all stars which makes it noticeable also by hobby watchers. It is one of the least active red dwarfs known, smaller and with 7-10 billion years older than our Sun (about 4.6 billion years), and represents an ideal target to search for exoplanets.

Since 1997, several instruments gathered a large amount of measurements on the star’s subtle back and forth wobble. An analysis of the data collected up to 2015 suggested the wobble might be caused by a planet with an orbital period of about 230 days.

To confirm this theory, astronomers regularly monitored Barnard’s star using high-precision spectrometer such as the CARMENES planet-hunter spectrograph at the Calar Alto Observatory in Spain. The re-analysis of all 771 measurements detected a clear signal over a period of 233 days. This signal shows that Barnard's star is approaching and descending at about 1.2 meters per second in its shaking motion – which is about the speed of a person's gait. This was the first time that this type of exoplanet could be discovered with the so-called radial velocity method.

This discovery brought in the work of many scientists worldwide. "In Hamburg, we helped to redefine the mass of Barnard's star. Only then the measured speed of 1.2 meters per second can be used to determine the mass of the newly discovered planet," Andreas Schweitzer adds, co-author of the Hamburg Observatory of the University of Hamburg.

The newly discovered planet is called Barnard's star b (or GJ 699 b). It is a super-Earth, a large extrasolar planet with more than three times the mass of the Earth. He orbits his cool red home star near the so-called snow line – an orbit where water remains frozen. Therefore, in the absence of an atmosphere, the temperature is about -150 ° C, making the presence of liquid water on its surface unlikely.

"The discovery of a planet in our immediate neighborhood is a great motivation to continue to search for exoplanets surrounding neighboring stars and one day actually find a planet on which life would be possible," explains Andreas Schweitzer.

Original publication

I. Ribas, M. Tuomi, A. Reiners, R. P. Butler, J. C. Morales, M. Perger, S. Dreizler, C. Rodríguez-López, J. I. González Hernández, A. Rosich, F. Feng, T. Trifonov, S. S. Vogt, J. A. Caballero, A. Hatzes, E. Herrero, S. V. Jeffers, M. Lafarga, F. Murgas, R. P. Nelson, E. Rodríguez, J. B. P. Strachan, L. Tal-Or, J. Teske, B. Toledo-Padrón, M. Zechmeister, A. Quirrenbach, P. J. Amado, M. Azzaro, V. J. S. Béjar, J. R. Barnes, Z. M. Berdiñas, J. Burt, G. Coleman, M. Cortés-Contreras, J. Crane, S. G. Engle, E. F. Guinan, C. A. Haswell, Th. Henning, B. Holden, J. Jenkins, H. R. A. Jones, A. Kaminski, M. Kiraga, M. Kürster, M. H. Lee, M. J. López-González, D. Montes, J. Morin, A. Ofir, E. Pallé, R. Rebolo, S. Reffert, A. Schweitzer, W. Seifert, S. A. Shectman, D. Staab, R. A. Street, A. Suárez Mascareño, Y. Tsapras, S. X. Wang, G. Anglada-Escudé, A super-Earth planet candidate orbiting at the snow-line of Barnard’s star, Nature (2018).

https://www.nature.com/articles/s41586-018-0677-y

The radial velocity method

Precision spectrometers measuring the Doppler effect were used for the researches. The Doppler effect is a temporal compression or elongation of a signal with changes in the distance between transmitter and receiver. In everyday life, one knows the phenomenon that an approaching car sounds different than a departing vehicle. Now, if a stellar object moves away from the earth, the observed light becomes slightly less energetic and therefore redder. The light becomes energy-rich and blue as the star moves towards the Earth.

For more information

Hamburg Observatory of the University of Hamburg: https://www.hs.uni-hamburg.de

Contact:

Andreas Schweitzer
Hamburg Observatory
University of Hamburg
Phone: +49 40 42838-8416
Email: aschweitzer@hs.uni-hamburg.de

Heiko Fuchs
University of Hamburg
Faculty of Mathematics, Informatics and Natural Sciences
Office of the dean
Phone: +49 40 42838-7193
Email: heiko.fuchs@uni-hamburg.de

Wissenschaftliche Ansprechpartner:

Andreas Schweitzer
Hamburg Observatory
University of Hamburg
Phone: +49 40 42838-8416
Email: aschweitzer@hs.uni-hamburg.de

Originalpublikation:

A super-Earth planet candidate orbiting at the snow-line of Barnard’s star, Nature (2018).

https://www.nature.com/articles/s41586-018-0677-y

Birgit Kruse | idw - Informationsdienst Wissenschaft

More articles from Physics and Astronomy:

nachricht New method gives microscope a boost in resolution
10.12.2018 | Rudolf-Virchow-Zentrum für Experimentelle Biomedizin der Universität Würzburg

nachricht A new 'spin' on kagome lattices
10.12.2018 | Boston College

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

Im Focus: Substitute for rare earth metal oxides

New Project SNAPSTER: Novel luminescent materials by encapsulating phosphorescent metal clusters with organic liquid crystals

Nowadays energy conversion in lighting and optoelectronic devices requires the use of rare earth oxides.

Im Focus: A bit of a stretch... material that thickens as it's pulled

Scientists have discovered the first synthetic material that becomes thicker - at the molecular level - as it is stretched.

Researchers led by Dr Devesh Mistry from the University of Leeds discovered a new non-porous material that has unique and inherent "auxetic" stretching...

Im Focus: The force of the vacuum

Scientists from the Theory Department of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science (CFEL) in Hamburg have shown through theoretical calculations and computer simulations that the force between electrons and lattice distortions in an atomically thin two-dimensional superconductor can be controlled with virtual photons. This could aid the development of new superconductors for energy-saving devices and many other technical applications.

The vacuum is not empty. It may sound like magic to laypeople but it has occupied physicists since the birth of quantum mechanics.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

Expert Panel on the Future of HPC in Engineering

03.12.2018 | Event News

 
Latest News

New method gives microscope a boost in resolution

10.12.2018 | Physics and Astronomy

Carnegie Mellon researchers probe hydrogen bonds using new technique

10.12.2018 | Life Sciences

ETRI exchanged quantum information on daylight in a free-space quantum key distribution

10.12.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>