Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Astronomers close in on planets that could be masters of survival


Two independent groups of astronomers, one led by Simona Ciceri of the Max Planck Institute for Astronomy, have discovered an unusually massive planet which orbits a red giant star. The planet, Kepler-432b, is one of a total of just five known planets which orbit red giant stars at a fairly close distance. Previously, it had been thought that such planets would be swallowed by their host stars fairly quickly; the new discovery indicates they might survive for longer than previously thought.

First hints of the existence of the planet Kepler-432b came from measurements of NASA’s Kepler space telescope. The telescope recorded tiny dips in the brightness of the planet’s host star, caused by the planet passing directly between the star and observers on Earth and blocking some of the star’s light (“planetary transit”). Such dips, however, can have causes other than orbiting planets.

The 2.2 meter telescope at Calar Alto observatory, which was used to confirm the existence of the planet Kepler-432b

Image: MPIA

Confirmation that Kepler had indeed found a planet came only with the recent independent observations by two groups of astronomers: a group led by Simona Ciceri of the Max Planck Institute for Astronomy (MPIA) and one led by Mauricio Ortiz of the Centre for Astronomy of Heidelberg University (ZAH).

The astronomers had used the CAFE spectrograph at the 2.2 meter telescope at Calar Alto Observatory to detect the planet’s traces in the spectrum of the star (“radial velocity method”). The group from ZAH also observed Kepler-432b with the Nordic Optical Telescope on La Palma (Canary Islands).

The combination of the observations by Kepler and with the CAFE spectrograph provided sufficient data to enable the astronomers reconstruct the planet’s size and mass. Kepler-432b turns out to be unusual in more than one respect. It is about the same size as Jupiter, but with six times Jupiter’s mass, making it unusually dense. Its orbit is an elongated ellipse, leading to temperature variations between 500 and 1000 degrees Celsius as the planet moves around its host star.

But the most puzzling aspect of Kepler-432b might be why it and other similar planets exist in the first place. The problem is the planet’s proximity to its host star. Of the nearly 1900 exoplanets known, around 50 orbit stars in the later stages of their lives: red giant stars, which have swollen to between ten and a hundred times their former size as their outer regions have heated up.

For a star’s planets, this swelling-up can be fatal: Planets too close to the star will be swallowed up, and planets orbiting too close to the red giant’s surface are likely to be drawn in and swallowed within tens or a few hundreds of million years – a short time-span compared with the more than 10 billion years’ life-time of a star like our Sun.

Until now, astronomers have observed 5 planets, including Kepler-432b, which are unusually close to their red giant hosts. Of these, only two, namely Kepler-432b and Kepler-91b have been observed sufficiently closely to determine both their mass and their size (radial velocity and transit data). Another two have been detected only by measuring their planetary transits, while one has been found using spectral measurements only (radial velocity method).

If a phenomenon is fairly short-lived, astronomers do not expect to observe many examples of it. Simona Ciceri, the PhD student at the Max Planck Institute for Astronomy who led the first of the studies of Kepler-432b, says: “At this point, there are two possibilities: Either we have been unusually lucky to observe two rare, close planetary orbits such as those of Kepler-432b and Kepler-91b.

Or else, planets like these survive for much longer than was previously assumed.” Now the data is in, it’s the turn of those who simulate planetary interaction with giant stars to re-check their simulations and to come up with an answer.

Even though the planet has proven a master of survival so far, in the long run, there will be no escape: “The days of Kepler-432b are numbered,” adds Mauricio Ortiz, the PhD student at Heidelberg University who led the other study of the planet. “In less than 200 million years, Kepler-432b will be swallowed by its continually expanding host star.”

Contact information

Simona Ciceri (first author)
Max Planck Institute for Astronomy
Phone: +49 6221 528-351

Luigi Mancini (co-author)
Max Planck Institute for Astronomy
Phone: +49 6221 528-454

Markus Pössel (public information officer)
Max Planck Institute for Astronomy
Phone: +49 6221 528-261

Background information

The work described here has been published by two independent groups as

S. Ciceri, J. Lillo-Box, J. Southworth, L. Mancini, T. Henning, D. Barrado: Kepler-432 b: a massive planet in a highly eccentric orbit transiting a red giant, Astronomy & Astrophysics 573 (January 2015), doi: 10.1051/0004-6361/201425145

M. Ortiz, D. Gandolfi, S. Reffert, A. Quirrenbach, H.J. Deeg, R. Karjalainen, P. Montañés-Rodríguez, D. Nespral, G. Nowak, Y. Osorio and E. Palle: Kepler-432 b: a massive warm Jupiter in a 52 day eccentric orbit transiting a giant star, Astronomy & Astrophysics 573 (January 2015), doi: 10.1051/0004-6361/201425146

Weitere Informationen: - web version of this press release - original article by Ciceri et al. - original article by Ortiz et al.

Dr. Markus Pössel | Max-Planck-Institut für Astronomie

More articles from Physics and Astronomy:

nachricht NASA detects solar flare pulses at Sun and Earth
17.11.2017 | NASA/Goddard Space Flight Center

nachricht Pluto's hydrocarbon haze keeps dwarf planet colder than expected
16.11.2017 | University of California - Santa Cruz

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: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>



Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

More VideoLinks >>>