Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

CoRoT unveils a young active star resembling the young Sun

23.12.2008
The CoRoT satellite, a space mission led by the French Space Agency CNES with the participation of Austria, Belgium, Brazil, Germany, Spain and the European Space Agency, ESA (RSSD and Science programme, that includes an Italian contribution), has recently observed a star analogous to the young Sun at an age of approximately 500 million years, named CoRoTExo-2a.

This star is accompanied by a giant planet orbiting around it in only 1.7 days, that was discovered by the CoRoT Extrasolar Planet Team. An investigation on the intrinsic variations of the star has been carried out by another international team, led by astronomers of the Italian National Institute for Astrophysics (INAF) at Catania Astrophysical Observatory with the support of the Italian Space Agency (ASI). It will be published on Tuesday, Dec. 23, 2008 on Astronomy & Astrophysics.

With its very high photometric accuracy and the long duration of continuous observations, CoRoT has been able for the first time to measure the variations of the intensity of the star and follow it for more than 150 days. These unique data show flux variations of about 6 percent, at least 20 times greater than those of the present Sun, with a periodic modulation of 4.5 days. They are produced by spots, analogous to sunspots, but having a correspondingly larger area, that evolve continuously as the star rotates. CoRoT observations revealed an unexpected phenomenon: the spotted area oscillates with a mini-cycle of only 29 days. In the Sun, such mini-cycles have sometimes been observed close to the maxima of the main 11-year cycle, with a period of about 150 days. They have been accompanied by corresponding modulations in the frequency and intensity of solar flares, whose energetic radiation impacted upon the planets. The shorter period observed in CoRoT-Exo-2a may be due to its faster rotation or the perturbations induced by the close giant planet, orbiting at a distance of only 4.2 million kilometers from the star, i.e., only 3 percent the distance between the Sun and the Earth.

Our Sun, during the evolutionary stage corresponding to that of CoRoT-Exo-2a, was shining on the Earth when the processes that would have led to the appearance of life had just begun. The presence of an intense magnetic activity on the young Sun and its light variability certainly affected those processes. The study of Sun-like stars with the CoRoT satellite and other spaceborne or ground-based telescopes will contribute to our understanding of the influence of stars on their planets during those crucial phases of their evolution. In the specific case of CoRoTExo-2a, additionally interesting results are expected from future observations, also with ground-based telescopes, to confirm the possible effect of the giant planet on stellar magnetic activity.

Antonino Francesco Lanza | alfa
Further information:
http://www.inaf.it
http://www.aanda.org/doi/10.1051/0004-6361:200810591/pdf

More articles from Physics and Astronomy:

nachricht Transportable laser
23.01.2018 | Physikalisch-Technische Bundesanstalt (PTB)

nachricht New for three types of extreme-energy space particles: Theory shows unified origin
23.01.2018 | Penn State

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: Optical Nanoscope Allows Imaging of Quantum Dots

Physicists have developed a technique based on optical microscopy that can be used to create images of atoms on the nanoscale. In particular, the new method allows the imaging of quantum dots in a semiconductor chip. Together with colleagues from the University of Bochum, scientists from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute reported the findings in the journal Nature Photonics.

Microscopes allow us to see structures that are otherwise invisible to the human eye. However, conventional optical microscopes cannot be used to image...

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Rutgers scientists discover 'Legos of life'

23.01.2018 | Life Sciences

Seabed mining could destroy ecosystems

23.01.2018 | Earth Sciences

Transportable laser

23.01.2018 | Physics and Astronomy

VideoLinks Science & Research
Overview of more VideoLinks >>>