LkCa 15b

Links Transitional disc with a dust-free inner core of 50  AE (English AU.) Diameter,
right image section with Planet LkCa 15b (blue), dust and gas (red) and location of the star LkCa 15

LkCa 15b is an extrasolar protoplanet about 450 light years from Earth .

discovery

The celestial object LkCa 15b was discovered in 2011 at the Keck Observatory in Hawaii by astronomers Adam Kraus from the Institute for Astronomy of the University of Hawaii and Michael Ireland from Macquarie University in Australia . Only the combination of two techniques to exclude the bright starlight made direct observation possible. These were adaptive optics on the telescope mirror using powerful computers and the use of a special interferometric technique .

Later, an international group of astronomers led by Stephanie Sallum from the University of Arizona made further observations on the celestial object.

description

LkCa 15b is located within a large molecular cloud in the constellation Taurus . This region, about 450 light years from Earth, is the closest star formation region to Earth . There is LkCa 15b with the two proto planet LkCa 15c and 15d LkCa a planetary system . The central star is the young star LkCa 15 , which is about 2 million years old . The celestial objects are located in the approximately 50  AU (astronomical unit) large, largely dust and gas-free interior of a transitional disk . According to the astronomers, infrared images and the characteristic radiation of 9700 ° C hot hydrogen gas (hydrogen glow) show that planets are forming. The glow of glowing dust could be detected, which falls on the protoplanet LkCa 15b and causes it to grow. The processes were proven by long-term observations with the Large Binocular Telescope in Arizona and the Magellan Telescope in Chile . According to the co-discoverer Adam Kraus, LkCa 15b is a Jupiter- like gas planet surrounded by dust and gas . According to the measurements, it should have a considerably stronger magnetic field than that of Jupiter. It is about 20 times as strong as the earth's magnetic field .

LkCa 15b is the first and the youngest observed exoplanet that is still forming due to accretion . By further observing the planet, the astronomers want to test theories of planet formation.

Web links

• Astronomy: Researchers observe the birth of planets in: Spiegel online from November 19, 2015
• First photo of a planet birth at: scinexx .de
• Researchers track the birth of a planet at: ingenieur.de from November 23, 2015
• Accreting protoplanets in the LkCa 15 transition disk Article preview in: Nature from November 18, 2015 (English)
• Zhaohuan Zhu: Growing planet brought to light. Nature 527 , p. 310-311 (November 19, 2015). See also: Spectrum of Science May 2016, p. 10/11, Current Research: Live connection to the birth of planets.
• Data sheet for the Planet LKCA 15 b at exoplanet.eu (English)

Individual evidence

1. ↑ Sarah Zielinski: A Planet Spotted As It Begins To Form in: Smithsonian Magazine, October 21, 2011.
2. ↑ UH Astronomer Finds Planet in the Process of Forming as press release from the Institute for Astronomy - University of Hawai .
3. ↑ ^{a b} Astronomers observe the birth of a planet at: heise online from November 19, 2015.
4. ↑ Alina Schadwinkel: Astronomers observe the birth of a planet in: Die Zeit from November 18, 2015.