2014-04-30 19:00
Observations carried out using ESO’s VLT (Very Large Telescope) allowed the determination of the first extrasolar planet rotation period. It turned out that one day “on Beta Pictoris b lasts just eight hours. This is much less than on any planet in the solar system – Beta Pictoris planet’s equator b moves at a speed of almost 100 000 km / h relationship between mass and turnover rate observed in the solar system, can now be tested as in the case of extrasolar planets. Similar techniques allow astronomers to perform in the future, detailed maps of extrasolar planets by the European Extremely Large Telescope (E-ELT).
Planet Beta Pictoris b exoplanet orbits visible to the naked eye star Beta Pictoris [1], [2], that is, 63 light years away from Earth and is visible in the constellation Painter. Planet discovered almost six years ago, was one of the first exoplanets imaged directly. It orbits its star at a distance of only eight times larger than the Earth-Sun distance (eso1024) – making it the closest planet relative to its star from directly photographed. [3]
Dutch team of astronomers from Leiden University and the Netherlands Institute for Space Research (SRON) used the instrument on the VLT CRIRES and discovered that the speed of rotation of the planet Beta Pictoris Equatorial b is almost 100 000 km / h For comparison, Jupiter equator rotates at a speed of about 47 000 km / h [4], and the terrestrial only 1700 km / h [5]. Beta Pictoris b is 16 times larger and 3000 times more massive than Earth, and the day on this planet takes only 8 hours.
, I do not know why some planets rotate rapidly and others more slowly “, says co-author Remco de Kok, , but the first measurement of rotation exoplanets shows that the trend seen in the solar system, according to which the more massive planets rotate faster is true also for extrasolar planets. Must be a universal consequence the way in which the planets formed. “Beta Pictoris b is a planet very young, is only 20 million years (compared to 4.5 billion years of the Earth) [6]. It is believed that over time the planet cooled and shrinks, causing still faster rotation [7]. On the other hand, may play a role other processes changing the rotation of the planet. For example, the rotation of the Earth around its axis is slowed down by tidal interactions with the Moon.
Astronomers used a very precise technique called spectroscopy wysokodyspersyjną to separate the light into its component colors – different wavelengths in the spectrum. The principle of Doppler effect (or Doppler shift) allowed the use of a change in wavelength to detect that the different parts of the planets move at different speeds and in opposite directions relative to the observer. After carefully removing the effects of the much brighter star, scientists were able to pluck the signal from the planet’s rotation. “We measured the wavelength of the radiation emitted by the planet with an accuracy of one part in one hundred thousand, so that the measurements are sensitive to Doppler effect, which revealed the speed of the emitting object. “ says Ignas Snellen principal author. ,, With this technique, we found that different parts of the planet’s surface are moving in our direction, or moving away from us at different speeds, which can only be explained by the fact that the planet rotates around its axis. “This technique is closely related to Doppler imaging, which was used for decades for mapping the surface of the star, and recently also map a brown dwarf [8] – Luhman 16B (eso1404). rapid turnover of Beta Pictoris b is the in the future it will be possible to develop a global map of the planet, a potential-evident systems of clouds and big storms.
, this technique can be applied to a much larger group of exoplanets thanks to the incredible resolution and sensitivity of the E-ELT and wysokodyspersyjnego imaging spectrograph. Planned Mid-infrared E-ELT Imager and Spectrograph (METIS) will be able to perform a global map of extrasolar planets and determine ownership of much smaller planets than Beta Pictoris b “ says Bernhard Brandl, chief project scientist and co-author of METIS.
Notes
[1] Beta Pictoris has many other signs, such as HD 39060, SAO 234134 and HIP 27321.
[2] Beta Pictoris is the most famous example of a star surrounded by a disk. It is known that the disk extends to a distance of about 1000 times larger than the distance Earth-Sun. Past observations of the planet around Beta Pictoris have been reported in eso0842, eso1024 and eso1408.
[3] The observations were made using the technique of adaptive optics, which compensates for turbulence in the Earth’s atmosphere, disrupting images obtained even in the best astronomical sites in the world . This technique allows astronomers to obtain super-sharp images, almost as good as from space. [4] Because Jupiter has no solid surface, for which one could determine the pace of the market, we have given the speed of the atmosphere at the equator, which is 47 000 km / h[5] The rotation speed of the Earth at the equator is 1,674.4 km / h
[6] Earlier measurements suggested that the system is younger.
[7] is a consequence of the principle of conservation of angular momentum. The same effect causes the rotation of the skater on the ice accelerates rapidly when pressed his hands to the body.
[8] Brown dwarfs are often called “failed stars” because, in contrast to stars like the sun, I never become hot enough to start nuclear fusion reactions.more
The results described in the article Fri “Fast spin of a young extrasolar planets”, I. Snellen et al., Which will be released on May 1, 2014, in Nature .
Composition of the research team: Ignas AG Snellen (Leiden Observatory, Leiden University, Leiden, The Netherlands), Remco J. de Kok (SRON Netherlands Institute for Space Research, Utrecht, The Netherlands), Ernst JW de Mooij (Leiden Observatory) and Simon Albrecht (Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, USA; Leiden Observatory)ESO is the foremost intergovernmental astronomy organization in Europe and the most productive astronomical observatory in the world. It is supported by 15 countries: Austria, Belgium, Brazil, Czech Republic, Denmark, Finland, France, Spain, the Netherlands, Germany, Portugal, Switzerland, Sweden, United Kingdom and Italy. ESO carries out an ambitious program focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organizing cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope (Very Large Telescope), the world’s most advanced astronomical observatory in visible light and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope instrument and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 39-meter European Extremely Large Telescope (European Extremely Large optical / near-infrared Telescope – E-ELT), which will become “the world’s biggest eye on the sky”.
Links
- Scientific Publication
- Photos VLT
- Photos CRIRES
- CRIRES instrument on the VLT
- More about METIS: A Mid- infrared E-ELT Imager and Spectrograph
Contact
Krzysztof Devil
Centre for Astronomy UMK
Torun, Poland
Tel.: + 48 513 733 282
E-mail: eson-poland@eso.org
Ignas Snellen of Leiden Observatory
Leiden, The Netherlands
Tel.: + 31 71 52 75 838
Tel. Mobile: +31 63 00 31 983
E-mail: snellen@strw.leidenuniv.nl
Richard Hook ESO Public Information Officer
Garching bei München, Germany
Tel.: +49 89 3200 6655 Tel
. Mobile: +49 151 1537 3591 E-mail
: rhook@eso.org
This is a translation of the Communication press ESO eso1414
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