An international team of astronomers, including five Carnegie scientists, reports the discovery of two new planets orbiting a very old star that is near to our own Sun. One of these planets orbits the star at the right distance to allow liquid water to exist on its surface, a key ingredient to support life.
Monthly Notices of the Royal Astronomical Society
Kapteyn’s Star, named after the Dutch astronomer, Jacobus Kapteyn, who discovered it at the end of the 19th century, is the second fastest-moving star in the sky and belongs to the Galactic halo, an extended group of stars orbiting our Galaxy on very elliptical orbits. With a third of the mass of the Sun, this red-dwarf can be seen with an amateur telescope in the southern constellation of Pictor.
The astronomers–including Carnegie’s Pamela Arriagada, Paul Butler, Steve Shectman, Jeff Crane, and Ian Thompson–used new data from the HARPS spectrometer at the European Southern Observatory’s La Silla observatory, the Planet Finding Spectrometer at the Magellan/Las Campanas Observatory in Chile, and the HIRES spectrometer at the W.M. Keck Observatory in Hawaii to measure tiny periodic changes in the motion of the star. The Doppler Effect enabled the scientists to deduce some properties of these planets, including their masses and orbital periods. Continue reading Two Planets Orbit Nearby Ancient Star→
European Space Agency (ESA) is planning to launch the Gaia mission by the end of 2013. That mission will study the ultra-cool dwarfs, which are the group of stars in the Milky Way, with a temperature below 2500K. They are among the most ancient celestial objects in our Galaxy and can help in the study of the most primitive chemical composition.
Actually the objectives of this astronomical study are “to create the largest and most precise three dimensional chart of our Galaxy by providing unprecedented positional and radial velocity measurements for about one billion stars in our Galaxy and throughout the Local Group.”
In a research paper, published in the journal Astronomy & Astrophysics, researchers have designed a method allowing Gaia to detect tens of ultra-cool dwarfs in the Milky Way. They have also developed the method to detect the physical parameters such as the temperature and gravity with little errors. These accurate descriptions will also increase the number of detected ultra-cool dwarfs.
Gaia will provide about one petabyte of information that will be processed and analyzed to get the results. About 400 scientists will collaborate in the project.
Astronomy is really an interesting field as Horace Mann quoted, “”Astronomy is one of the sublimest fields of human investigation. The mind that grasps its facts and principles receives something of the enlargement and grandeur belonging to the science itself. It is a quickener of devotion.”
Recently, scientists from MIT published a research paper in the journal Nature in which they showed their work of “Extremely metal-poor gas at a redshift of 7”. They utilized infrared spectrometer, which they placed onto the Magellan Telescope, a massive ground-based telescope in Chile. They calculated the elements and based on the observations about the heavy elements they believe that the earliest stars might have been formed 750 million years after the formation of Universe. “The first stars will form in different spots in the universe … it’s not like they flashed on at the same time,” Robert Simcoe, an associate professor of physics at MIT,said in a statement. “But this is the time that it starts getting interesting.” Continue reading Earliest stars were formed when the age of the Universe was…→