Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Hot Jupiter Exoplanet Discovery Opens Gateway to Understanding Evolution of Planetary Systems

17.01.2011
The discovery of a Hot Jupiter exoplanet that transfers orbital momentum to its host star may hold the key to a clearer understanding of the evolution of common planetary systems, according to findings presented this week by Dr. Edward Guinan, a professor of astronomy at Villanova University in Villanova, Pa. Guinan announced the find at a press conference held at the opening of the 217th American Astronomy Society meeting in Seattle, Washington.

The discovery is of special interest because it represents a rare case in which a research team was able to make an independent age determination of the planet system by studying the system’s faint red dwarf companion star. The discovery opens a new gateway to learning about the dynamics and evolution of many other planetary systems that also contain close-in hot-Jupiter type planets.

HD189733b, the Hot Jupiter exoplanet, orbits an orange (dwarf K) star HD18973A in the constellation Vulpecula (the Fox). It orbits at only three percent of the distance of the Earth from the Sun: i.e. ~0.03 AU) with an orbital period of only 2.2 days (for comparison the Earth takes 365 days to orbit our Sun). The host star is about 63 light-years away and has a mass and diameter about ~80 percent that of our Sun. This star, invigorated by its hot Jupiter planetary companion, appears to have been spun up (rotating ~ >2x faster than our Sun – having a ~12-day rotation period) and is gaining angular momentum from magnetic and tidal interactions with its close-in Jupiter-size planet. The star, however, is being spun-up at the expense of the planet’s orbital angular energy.

The loss in the planet’s orbital momentum in the past may explain why it (and other similar planetary systems) orbit so close to their host stars. While the planet is spiraling in toward the star, and is most likely doomed, there is a possibility that the interacting magnetic fields of the star and planet could create a tidal-magnetically locked orbit–rotation that might allow the planet to survive. The most likely scenario, however, is that the planet will draw closer to the star and its atmosphere will be eroded away by the star’s intense radiation and strong winds. The planet will ultimately be ripped apart by the star’s gravity if it survives the star’s radiation and winds.

HD 189733 Ab is a relatively rare eclipsing planetary system that was discovered in 2005 (by Buchy et al.) and has attracted much attention in astronomical circles because it hosts a transiting Hot Jupiter exoplanet. The system is relatively bright (e.g. can be seen with binoculars). The eclipses by the planet permit substantial information to be gained from observing the system inside and outside the planetary eclipses. For example, spectroscopic studies by other teams (e.g. G. Tinnetti et al.) reveal that its hot atmosphere contains water vapor, carbon dioxide, sodium, and, interestingly, organic molecules of methane and particulate haze.

The Villanova team, which includes undergraduates Thomas Santapaga and Ronald Ballouz, found that this system is about over five billion years old and that the Jupiter-size planet has been estimated to be very hot at ~1,500 degrees Fahrenheit by other researchers. HD189733b has one of the shortest known orbital periods of only P = 2.22 days and is only 0.031AU from its host star (i.e. only ~8.75x the radius of the host star).

(A scale model of the system is provided.) The exoplanet system includes a cool red dwarf companion star (HD 189733B). This faint companion star is located at ~12” distance to the K-dwarf. At the distance of HD 189733 this corresponds to a separation of ~220 AU/ For comparison this 220x the distance of the Earth from the Sun / or over 5.5x further than the distance of Pluto from the Sun.) The presence of this red dwarf star makes a reliable age estimate of the binary system possible via activity-age relations developed at Villanova.

“Planetary systems like HD 189733 with short period, “hot-Jupiter” planets are very common – over a hundred have been discovered so far,” Guinan noted. He continued, “HD 189733 and dozens of other planetary systems like it, many of which were recently discovered by NASA’s Kepler mission, may also be undergoing the same process of strong magnetic interactions between their close-in large planets and their host stars.”

“The big clue that is different here is that we know the age of HD 189733 from the study of its coeval faint companion star.” This discovery should help in our endeavors to try to better understand the dynamics of other planetary systems like HD 189733, he added.”

Of the over 500 exoplanets that have been discovered to date, HD 189733 is the only one of a handful whose age and physical properties have been well determined.

“This study may help explain how and why hot Jupiters form and evolve. It may help explain this whole class of planets,” Guinan remarked.

In conducting this study the research team, which includes Villanovans Thomas Santapaga, Ronald L. Ballouz, Scott E. Engle, Laurence E. DeWarf, along with Styliani (Stella) Kafka from the Carnegie Institute in Washington, D.C.’s Department of Terrestrial Magnetism, observed the exoplanet system using the Clay Telescope at the Carnegie Institution of Washington’s Las Campanas Observatory in Chile. Observations of the eclipse timings of HD 189733 continue at Villanova using the Four College Automatic Photoelectric Telescope (FCAPT) located in southern Arizona. The eclipse timings made with this telescope over time could provide evidence that the orbital period of the system is indeed decreasing.

The research project is funded through The National Science Foundation‘s Research at Undergraduate Institutions and grants from NASA.

Guinan’s Jan. 10 presentation of the team’s findings at the 217th AAS Meeting are from a paper titled, “Some Like It Hot” – Evidence for the Shrinking Orbit of the 2.2-day Transiting Hot Jupiter Exoplanet HD 189733b – Evidence of Transfer of Planet Orbital Momentum to its Host Star” (AAS 217th Meeting Abstract 343.12, P. 566).

“One of the most amazing results of our team’s research is that a planet-size body that is only 1/1000x times the mass of the host star can make such a large impact by magnetically interacting with its host star to the extent that it causes the star to spin up, activating a strong magnetic dynamo of the star that produces the observed strong X-ray coronal emissions, large starspots and other phenomena,” Guinan concluded.

Kathleen Scavello | Newswise Science News
Further information:
http://www.villanova.edu

More articles from Physics and Astronomy:

nachricht NASA spacecraft investigate clues in radiation belts
28.03.2017 | NASA/Goddard Space Flight Center

nachricht Researchers create artificial materials atom-by-atom
28.03.2017 | Aalto University

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 Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Transport of molecular motors into cilia

28.03.2017 | Life Sciences

A novel hybrid UAV that may change the way people operate drones

28.03.2017 | Information Technology

NASA spacecraft investigate clues in radiation belts

28.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>