Hosted by world-renowned astrophotographer Adam Block at the UA’s Mount Lemmon SkyCenter, a group of sky and astronomy enthusiasts watched Venus cross the sun from the highest vantage point in Southern Arizona.
On Nov. 24, 1639, in the tiny village of Much Hoole not far from Liverpool, England, a poor farmer’s son and self-taught astronomer affixed a sheet of paper in front of a makeshift telescope pointed at the sun and waited.
Thirty-five minutes before sunset, a dark, round spot appeared right next to the bright disc that was the sun’s face projected on the paper, and made Jeremiah Horrocks, only 20 years old at the time, the first known human to predict, observe and record a transit – the passage of a planet across the sun as seen from Earth.
Almost 373 years later, a group of sky enthusiasts is gathered beneath the dome of one of the University of Arizona’s observatories on Mount Lemmon just north of Tucson, Ariz. (more…)
Massive detector homes in on cosmic ray production
IceCube, an international collaboration involving University of Delaware scientists, is shedding new light on cosmic ray production.
Although cosmic rays were discovered 100 years ago, their origin remains one of the most enduring mysteries in physics. Now, the IceCube Neutrino Observatory, a massive detector in Antarctica, is homing in on how the highest energy cosmic rays are produced. (more…)
A team led by UCLA research astronomer Michael Rich has used a unique telescope to discover a previously unknown companion to the nearby galaxy NGC 4449, which is some 12.5 million light years from Earth. The newly discovered dwarf galaxy had escaped even the prying eyes of the Hubble Space Telescope.
The research is published Feb. 9 in the journal Nature.(more…)
*For his discoveries about the lives and deaths of stars, the exotic physics of black holes and the origin of chemical elements, UA Regents’ Professor David Arnett has been honored with the Henry Norris Russell Lectureship.*
What happens when a star dies? How does a black hole form? What makes the chemical elements that form the building blocks of stars, planets and living beings?
Those are the kinds of questions that have fascinated David Arnett, a Regents’ Professor at the University of Arizona’s Steward Observatory, from an early age. (more…)
PASADENA, Calif. — The Herschel Space Observatory has revealed how much dark matter it takes to form a new galaxy bursting with stars. Herschel is a European Space Agency cornerstone mission supported with important NASA contributions.
The findings are a key step in understanding how dark matter, an invisible substance permeating our universe, contributed to the birth of massive galaxies in the early universe. (more…)
The National Science Foundation has signed a five-year, $34.5-million agreement with the University of Wisconsin-Madison to operate a unique telescope–a cubic kilometer in volume–buried in the Antarctic ice sheet between 1,400 meters and 2,400 meters deep.
The collaborative agreement covers the cost of operating the IceCube Neutrino Observatory, located in the ice under the U.S. Amundsen-Scott South Pole Station. The observatory records the rare collisions of neutrinos, elusive sub-atomic particles, with the atomic nuclei of the water frozen into ice. Neutrinos come from the sun, cosmic rays interacting with the Earth’s atmosphere, and dramatic astronomical sources such as exploding stars in the Milky Way and other distant galaxies. Trillions of neutrinos stream through the human body at any given moment, but they rarely interact with regular matter, and researchers want to know more about them and where they come from. (more…)
*Initial science results on comet released from University of Maryland, much more to come UMD scientists say.*
Jets Galore. This enhanced image, one of the closest taken of comet Hartley 2. Image credit: University of Maryland
COLLEGE PARK, Md. – One of the biggest comet findings coming out of the amazing images and data taken by the University of Maryland-ledEPOXI mission as it zipped past comet Hartley 2 last week is that dry ice is the ‘jet’ fuel for this comet and perhaps many others.
Images from the flyby show spectacular jets of gas and particles bursting from many distinct spots on the surface of the comet. This is the first time images of a comet have been sharp enough to allow scientists to link jets of dust and gas with specific surface features. Analysis of the spectral signatures of the materials coming from the jets shows primarily CO2 gas (carbon dioxide) and particles of dust and ice.
“Previously it was thought that water vapor from water ice was the propulsive force behind jets of material coming off of the body, or nucleus, of the comet,” said University of Maryland Astronomy Professor Jessica Sunshine, who is deputy principal investigator for the EPOXI mission. “We now have unambiguous evidence that solar heating of subsurface frozen carbon dioxide (dry ice), directly to a gas, a process known as sublimation, is powering the many jets of material coming from the comet. This is a finding that only could have been made by traveling to a comet, because ground based telescopes can’t detect CO2 and current space telescopes aren’t tuned to look for this gas,” Sunshine said.(more…)
