Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The diamond planet

31.08.2011
Radio wave observations show the transformation of a galaxy into a millisecond pulsar and its companion planet

A star that changes into a diamond planet? What sounds like science fiction is apparently reality. The discovery was made by an international team of scientists from Australia, Italy, Great Britain, the USA and Germany, including Michael Kramer from the Max Planck Institute for Radio Astronomy in Bonn. The researchers found the diamond planet with the help of the 64-metre Parkes radio telescope in Australia. The planet apparently orbits around an unusual, very dense star, a pulsar.


A strange pair: The picture shows the PSR J1719-1438 millisecond pulsar with 5.7 ms pulse period in the centre and the orbit of the planet compared to the size of the sun (marked in yellow). © Matthew Bailes


The 64-metre Parkes radio telescope in Australia.
© SIRO Astronomy and Space Science (CASS)

Pulsars represent the very last stages of star formation. They are rapidly rotating neutron stars the size of a small city which emit a highly focused beam of radio waves. As the star rotates, the beam sweeps over the earth – like the beam of light from a lighthouse – and radio telescopes detect a regular signal which seems to pulsate: thus the name pulsar.

With the newly discovered pulsar, which is known as PSR J1719-1438, the astronomers noticed a regular modulation in the arrival times of the signals. This “disturbance” is caused by the gravitation of a low-mass companion. The type of modulation tells the researchers quite a lot about the small celestial body: it has a diameter of only 60,000 kilometres and is therefore half as big as Jupiter. It orbits the pulsar in just two hours and ten minutes, at a distance of 600,000 kilometres – that’s only slightly less than the radius of our sun. Thus the planet orbits so close to the pulsar that its gravity should really rip it apart.

“The density of the planet is at least as great as that of platinum; this tells us a lot about its origin,” says the team leader, Matthew Bailes from Swinburne University of Technology in Australia. The scientists believe that the companion planet is the tiny core of a once-massive star. It only just managed to escape destruction as the rest of its material was being siphoned off by the pulsar.

J1719-1438 is an extremely rapidly rotating type of neutron star, which is known as a millisecond pulsar. It spins around its own axis more than 10,000 times per minute, has 1.4 times the mass of the sun, but a radius of only 20 kilometres or so. Around 70 percent of pulsars have partners of various types. The astronomers suspect that it is these companions which transfer mass when they are still stars and thus accelerate an old, slowly rotating pulsar to a very high orbital speed. The result is a rapidly rotating millisecond pulsar with a companion whose mass is greatly diminished - often a white dwarf.

In PSR J1719-1438 the pair is so close together that the companion can only be a white dwarf with greatly reduced mass which has lost all its outer layers and more than 99.9 percent of its original mass. The remnant must consist predominantly of carbon and oxygen because lighter elements, such as hydrogen and helium, cannot explain the data obtained from the observations. The density derived leads to the conclusion that the material is certain to be in a crystalline state; a large part of the star could therefore have a diamond-like structure.

“The ultimate fate of this binary star depends on the mass and orbital period of the donor star at the time the mass was transferred. The rare occurrence of millisecond pulsars with planet-mass companions means that the formation of such exotic planets is the exception rather than the rule, and requires a combination of special circumstances,” says Benjamin Stappers from the University of Manchester.

The data on the pulsar-planet pair were confirmed with follow-up observations with the Lovell radio telescope in Great Britain and one of the two Keck telescopes on Hawaii. The system is around 4,000 light years away towards the Serpens (Serpent) constellation in the plane of our Milky Way. The pulsar itself was identified among a total of 200,000 gigabytes of data – with the help of special analytical programs on supercomputers at Swinburne University of Technology, the University of Manchester and the INAF-Osservatorio Astronomico di Cagliari on Sardinia.

The project is part of a systematic search for pulsars in the entire firmament in which the 100-metre Effelsberg radio telescope, belonging to the Max Planck Institute for Radio Astronomy, contributes measurements in the northern hemisphere. “What we have here is the largest and most sensitive mapping of pulsars in the whole sky ever conducted,” says Michael Kramer, Director at the Max Planck Institute in Bonn. “We anticipate a series of exciting new findings with this programme. It is good to see that a start has already been made and more will follow. After all, we want to find out a great deal more about pulsars and fundamental physics in the years to come.”

Contact
Dr. Norbert Junkes
Press and Public Relations
Max Planck Institute for Radio Astronomy, Bonn
Phone: +49 228 525-399
Fax: +49 228 525-438
Email: njunkes@mpifr-bonn.mpg.de
Prof. Dr. Michael Kramer
Direktor
Max Planck Institute for Radio Astronomy, Bonn
Phone: +49 228 525-278
Fax: +49 228 525-436
Email: mkramer@mpifr-bonn.mpg.de
Publication reference
M. Bailes et al.
Transformation of a Star into a Planet in a Millisecond Pulsar Binary
Science, August 26, 2011

Dr. Norbert Junkes | EurekAlert!
Further information:
http://www.mpg.de/4406441/diamond_planet

More articles from Physics and Astronomy:

nachricht Further Improvement of Qubit Lifetime for Quantum Computers
09.12.2016 | Forschungszentrum Jülich

nachricht Electron highway inside crystal
09.12.2016 | Julius-Maximilians-Universität Würzburg

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: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>