ANN ARBOR, Mich.— Why is the universe magnetized? It’s a question scientists have been asking for decades. Now, an international team of researchers including a University of Michigan professor have demonstrated that it could have happened spontaneously, as the prevailing theory suggests.
The findings are published in the Jan. 26 edition of Nature. Oxford University scientists led the research. (more…)
A University of Exeter astrophysicist has shown what sunsets look like on planets outside our solar system.
He has worked out the colour of sunsets on two planets: HD 209458 b and HD 189733 b, known as ‘extrasolar planets’ because they are outside our solar system.
Extrasolar planets orbit stars, in a similar way to the Earth orbiting the Sun. Professor Frédéric Pont of the University of Exeter has used the extrasolar planets’ ‘transmission spectrum’, taken by the Hubble Space Telescope, to work out the colour of the ‘sunsets’ created by these stars.
Writing on the website ExoClimes.com, where he has posted the two sunset images he has produced, Professor Pont said: “Unlike its sister planet HD ’189, the planet HD ’209 (‘Osiris’) has a sunset that looks truly alien. The star is white outside the atmosphere, since its temperature is close to that of the Sun. It then acquires a bluish tinge as it sinks deeper, because the absorption by the broad wings of the neutral sodium lines (the spectral lines responsible for the gloomy orange of sodium street lighting) remove the red and orange from the star light. (more…)
PASADENA, Calif. – Astronomers using data from NASA’s Kepler mission have discovered the three smallest planets yet detected orbiting a star beyond our sun. The planets orbit a single star, called KOI-961, and are 0.78, 0.73 and 0.57 times the radius of Earth. The smallest is about the size of Mars.
All three planets are thought to be rocky like Earth but orbit close to their star, making them too hot to be in the habitable zone, which is the region where liquid water could exist. Of the more than 700 planets confirmed to orbit other stars, called exoplanets, only a handful are known to be rocky. (more…)
Astronomers at Yale University have discovered what appear to be three fast-growing supermassive black holes in a relatively young, still-forming galaxy.
The discovery raises the possibility that this type of black hole continues to form billions of years after the Big Bang, challenging current theory. Astronomers previously thought all supermassive black holes emerged soon after the birth of the universe 13.7 billion years ago. (more…)
TORONTO, ON – Three astronomers at the University of Toronto have found the most numerous batch of young, supermassive stars yet observed in our galaxy: hundreds of thousands of stars, including several hundreds of the most massive kind –blue stars dozens of times heavier than our Sun. The light these newborn stars emit is so intense it has pushed out and heated the gas that gave them birth, carving out a glowing hollow shell about a hundred light-years across.
These findings will be published in the December 20 issue of Astrophysical Journal Letters. For the researchers, the next step is already clear: “By studying these supermassive stars and the shell surrounding them, we hope to learn more about how energy is transmitted in such extreme environments,” says Mubdi Rahman, a PhD candidate in the Department of Astronomy & Astrophysics at the University of Toronto, who led the work with his supervisors, Professors Dae-Sik Moon and Christopher Matzner. (more…)
PASADENA, Calif. — The existence of a world with a double sunset, as portrayed in the film Star Wars more than 30 years ago, is now scientific fact. NASA’s Kepler mission has made the first unambiguous detection of a circumbinary planet — a planet orbiting two stars — 200 light-years from Earth.
Unlike Star Wars’ Tatooine, the planet is cold, gaseous and not thought to harbor life, but its discovery demonstrates the diversity of planets in our galaxy. Previous research has hinted at the existence of circumbinary planets, but clear confirmation proved elusive. Kepler detected such a planet, known as Kepler-16b, by observing transits, where the brightness of a parent star dims from the planet crossing in front of it. (more…)
This glowing emerald nebula seen by NASA’s Spitzer Space Telescope is reminiscent of the glowing ring wielded by the superhero Green Lantern. In the comic books, the diminutive Guardians of the Planet “Oa” forged his power ring, but astronomers believe rings like this are actually sculpted by the powerful light of giant “O” stars. O stars are the most massive type of star known to exist.
Named RCW 120 by astronomers, this region of hot gas and glowing dust can be found in the murky clouds encircled by the tail of the constellation Scorpius. The green ring of dust is actually glowing in infrared colors that our eyes cannot see, but show up brightly when viewed by Spitzer’s infrared detectors. At the center of this ring are a couple of giant stars whose intense ultraviolet light carved out the bubble, though they blend in with the other stars when viewed in infrared. (more…)
*Our home galaxy belongs to a rare subset among the billions that populate the cosmos*
How unique is the Milky Way?
To find out, a group of researchers led by Stanford University astrophysicist Risa Wechsler compared the Milky Way to similar galaxies and found that just four percent are like the galaxy Earth calls home. (more…)
