ANN ARBOR — In findings that help astrophysicists understand our corner of the galaxy, an international research team has shown that the soft X-ray glow blanketing the sky comes from both inside and outside the solar system.
The source of this “diffuse X-ray background” has been debated for the past 50 years. Does it originate from the solar wind colliding with interplanetary gases within our solar system? Or is it born further away, in the “local hot bubble” of gas that a supernova is believed to have left in our galactic neighborhood about 10 million years ago? (more…)
ANN ARBOR — Moonless nights outside the Cerro Tololo astronomical observatory in Chile are so dark that when you look down, you can’t see your feet.
“You can’t see your hands,” said David Gerdes, physics professor at the University of Michigan. “But you can hold them up to the sky and see a hand-shaped hole with no stars in it. It’s really incredible.”
From this site in the Andes over the next five years, an international team will map one-eighth of the sky in unprecedented detail—aiming to make a time lapse of the past 8 billion years of a slice of the universe. Through the Dark Energy Survey, which began Aug. 31, more than 200 researchers from 25 institutions, including U-M, will search for answers to a fundamental question about the cosmos: Why is its expansion speeding up? (more…)
When a batch of bright cosmic objects first appeared in maps in 2008 made with data from the South Pole Telescope, astronomers at the University of Chicago’s Kavli Institute for Cosmological Physics regarded it only as an unavoidable nuisance.
The light sources interfered with efforts to measure more precisely the cosmic microwave background—the afterglow of the big bang. But the astronomers soon realized that they had made a rare find in South Pole Telescope’s large survey of the sky. The spectra of some of the bright objects, which is the rainbow of light they emit, were inconsistent with what astronomers expected from the well-known population of radio galaxies. (more…)
Space Station Commander Kevin Ford exchanged Valentine’s Day greetings with his adult kids Heidi and Anthony — he speeding by about 220 miles above Providence and they watching him fly past from Brown’s Ladd Observatory.
PROVIDENCE, R.I. [Brown University] — Rhode Islanders with their eyes skyward around 6 p.m. last Thursday might have noticed a curiously bright speck speeding across the evening sky. No, it wasn’t a UFO or an asteroid. It was the International Space Station, and for Providence resident Heidi Ford, it was dad’s office.
Heidi’s father Kevin Ford is currently the commander of the ISS. And with the help of Brown’s Ladd Observatory and astronomer Robert Horton, Heidi and her brother Anthony, who was visiting from Houston, got to see last week’s flyby close up while they talked to their dad on the phone. (more…)
EAST LANSING, Mich. — A Michigan State University astronomer is part of an international team of scientists that has discovered a galaxy so far, far away that its light was emitted not all that long after the Big Bang occurred.
The research of MSU’s physics and astronomy professor Megan Donahue and colleagues is detailed in the recent issue of the journal Nature. They found that this galaxy began emitting light “just” 490 million years after the Big Bang, when the universe was only 3.6 percent of its present age. (more…)
Berkeley Lab researchers make historic observation of rare Type 1a Supernova
Exploding stars called Type 1a supernova are ideal for measuring cosmic distance because they are bright enough to spot across the Universe and have relatively the same luminosity everywhere. Although astronomers have many theories about the kinds of star systems involved in these explosions (or progenitor systems), no one has ever directly observed one—until now.
In the August 24 issue of Science, the multi-institutional Palomar Transient Factory (PTF) team presents the first-ever direct observations of a Type 1a supernova progenitor system. Astronomers have collected evidence indicating that the progenitor system of a Type 1a supernova, called PTF 11kx, contains a red giant star. They also show that the system previously underwent at least one much smaller nova eruption before it ended its life in a destructive supernova. The system is located 600 million light years away in the constellation Lynx. (more…)
Even though it sounds like science fiction, researchers are taking a second look at a controversial idea that uses futuristic ships to shoot salt water high into the sky over the oceans, creating clouds that reflect sunlight and thus counter global warming.
The point of the paper — which includes updates on the latest study into what kind of ship would be best to spray the salt water into the sky, how large the water droplets should be and the potential climatological impacts — is to encourage more scientists to consider the idea of marine cloud brightening and even poke holes in it. In the paper, he and a colleague detail an experiment to test the concept. (more…)
PASADENA, Calif. — The faint, lumpy glow given off by the very first objects in the universe may have been detected with the best precision yet, using NASA’s Spitzer Space Telescope. These faint objects might be wildly massive stars or voracious black holes. They are too far away to be seen individually, but Spitzer has captured new, convincing evidence of what appears to be the collective pattern of their infrared light.
The observations help confirm the first objects were numerous in quantity and furiously burned cosmic fuel.
“These objects would have been tremendously bright,” said Alexander “Sasha” Kashlinsky of NASA’s Goddard Space Flight Center in Greenbelt, Md., lead author of a new paper appearing in The Astrophysical Journal. “We can’t yet directly rule out mysterious sources for this light that could be coming from our nearby universe, but it is now becoming increasingly likely that we are catching a glimpse of an ancient epoch. Spitzer is laying down a roadmap for NASA’s upcoming James Webb Telescope, which will tell us exactly what and where these first objects were.”(more…)
