Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Astronomers Directly Image Massive Star's 'Super-Jupiter'

20.11.2012
Astronomers using infrared data from the Subaru Telescope in Hawaii have discovered a "super-Jupiter" around the bright star Kappa Andromedae, which now holds the record for the most massive star known to host a directly imaged planet or lightweight brown dwarf companion.

Designated Kappa Andromedae b (Kappa And b, for short), the new object has a mass about 12.8 times greater than Jupiter's. This places it teetering on the dividing line that separates the most massive planets from the lowest-mass brown dwarfs. That ambiguity is one of the object's charms, say researchers, who call it a super-Jupiter to embrace both possibilities.


The "super-Jupiter" Kappa Andromedae b, shown here in an artist's rendering, circles its star at nearly twice the distance that Neptune orbits the sun. With a mass about 13 times Jupiter's, the object glows with a reddish color. Credit: NASA's Goddard Space Flight Center/S. Wiessinger

"According to conventional models of planetary formation, Kappa And b falls just shy of being able to generate energy by fusion, at which point it would be considered a brown dwarf rather than a planet," said Michael McElwain, a member of the discovery team at NASA's Goddard Space Flight Center in Greenbelt, Md. "But this isn't definitive, and other considerations could nudge the object across the line into brown dwarf territory."

Massive planets slowly radiate the heat leftover from their own formation. For example, the planet Jupiter emits about twice the energy it receives from the sun. But if the object is massive enough, it's able to produce energy internally by fusing a heavy form of hydrogen called deuterium. (Stars like the sun, on the other hand, produce energy through a similar process that fuses the lighter and much more common form of hydrogen.) The theoretical mass where deuterium fusion can occur -- about 13 Jupiters -- marks the lowest possible mass for a brown dwarf.

"Kappa And b, the previously imaged planets around HR 8799 and Beta Pictoris, and the most massive planets discovered by non-imaging techniques likely all represent a class of object that formed in much the same way as lower-mass exoplanets," said lead researcher Joseph Carson, an astronomer at the College of Charleston, S.C., and the Max Planck Institute for Astronomy in Heidelberg, Germany.

The discovery of Kappa And b also allows astronomers to explore another theoretical limit. Astronomers have argued that large stars likely produce large planets, but experts predict that this stellar scaling can only extend so far, perhaps to stars with just a few times the sun's mass. The more massive a young star is, the brighter and hotter it becomes, resulting in powerful radiation that could disrupt the formation of planets within a circumstellar disk of gas and dust.

"This object demonstrates that stars as large as Kappa And, with 2.5 times the sun's mass, remain fully capable of producing planets," Carson adds.

The research is part of the Strategic Explorations of Exoplanets and Disks with Subaru (SEEDS), a five-year effort to directly image extrasolar planets and protoplanetary disks around several hundred nearby stars using the Subaru Telescope on Mauna Kea, Hawaii. Direct imaging of exoplanets is rare because the dim objects are usually lost in the star's brilliant glare. The SEEDS project images at near-infrared wavelengths using the telescope's adaptive optics system, which compensates for the smearing effects of Earth's atmosphere, in concert with its High Contrast Instrument for the Subaru Next Generation Adaptive Optics and Infrared Camera and Spectrograph.

Young star systems are attractive targets for direct exoplanet imaging because young planets have not been around long enough to lose much of the heat from their formation, which enhances their brightness in the infrared. The team focused on the star Kappa And because of its relative youth -- estimated at the tender age of 30 million years, or just 0.7 percent the age of our solar system, based on its likely membership in a stellar group known as the Columba Association. The B9-type star is located 170 light-years away in the direction of the constellation Andromeda and is visible to the unaided eye.

Kappa And b orbits its star at a projected distance of 55 times Earth's average distance from the sun and about 1.8 times as far as Neptune; the actual distance depends on how the system is oriented to our line of sight, which is not precisely known. The object has a temperature of about 2,600 degrees Fahrenheit (1,400 Celsius) and would appear bright red if seen up close by the human eye.

Carson's team detected the object in independent observations at four different infrared wavelengths in January and July of this year. Comparing the two images taken half a year apart showed that Kappa And b exhibits the same motion across the sky as its host star, which proves that the two objects are gravitationally bound and traveling together through space. Comparing the brightness of the super-Jupiter between different wavelengths revealed infrared colors similar to those observed in the handful of other gas giant planets successfully imaged around stars.

A paper describing the results has been accepted for publication in The Astrophysical Journal Letters and will appear in a future issue.

The SEEDS research team is continuing to study Kappa And b to better understand the chemistry of its atmosphere, constrain its orbit, and search for possible secondary planets.

Coincidentally, the stellar association that hosts Kappa And also includes another famous high-mass star, HR 8799, which is one of the first where astronomers directly imaged an extrasolar planet. The system hosts several gas giant planets with masses and infrared colors similar to Kappa And b.

Francis Reddy
NASA's Goddard Space Flight Center, Greenbelt, Md.

Francis Reddy | EurekAlert!
Further information:
http://www.nasa.gov
http://www.nasa.gov/topics/universe/features/super-jupiter.html

More articles from Physics and Astronomy:

nachricht Artificial Intelligence Helps in the Discovery of New Materials
21.09.2016 | Universität Basel

nachricht Magnetic polaron imaged for the first time
19.09.2016 | 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: OLED microdisplays in data glasses for improved human-machine interaction

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.

“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...

Im Focus: Artificial Intelligence Helps in the Discovery of New Materials

With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.

Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...

Im Focus: Complex hardmetal tools out of the 3D printer

For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.

Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...

Im Focus: Launch of New Industry Working Group for Process Control in Laser Material Processing

At AKL’16, the International Laser Technology Congress held in May this year, interest in the topic of process control was greater than expected. Appropriately, the event was also used to launch the Industry Working Group for Process Control in Laser Material Processing. The group provides a forum for representatives from industry and research to initiate pre-competitive projects and discuss issues such as standards, potential cost savings and feasibility.

In the age of industry 4.0, laser technology is firmly established within manufacturing. A wide variety of laser techniques – from USP ablation and additive...

Im Focus: New laser joining technologies at ‘K 2016’ trade fair

Every three years, the plastics industry gathers at K, the international trade fair for plastics and rubber in Düsseldorf. The Fraunhofer Institute for Laser Technology ILT will also be attending again and presenting many innovative technologies, such as for joining plastics and metals using ultrashort pulse lasers. From October 19 to 26, you can find the Fraunhofer ILT at the joint Fraunhofer booth SC01 in Hall 7.

K is the world’s largest trade fair for the plastics and rubber industry. As in previous years, the organizers are expecting 3,000 exhibitors and more than...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Experts from industry and academia discuss the future mobile telecommunications standard 5G

23.09.2016 | Event News

ICPE in Graz for the seventh time

20.09.2016 | Event News

Using mathematical models to understand our brain

16.09.2016 | Event News

 
Latest News

Chains of nanogold – forged with atomic precision

23.09.2016 | Life Sciences

New leukemia treatment offers hope

23.09.2016 | Health and Medicine

Self-assembled nanostructures hit their target

23.09.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>