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Astronomy

Astronomy January 2015

The world's best-selling astronomy magazine offers you the most exciting, visually stunning, and timely coverage of the heavens above. Each monthly issue includes expert science reporting, vivid color photography, complete sky coverage, spot-on observing tips, informative telescope reviews, and much more! All this in a user-friendly style that's perfect for astronomers at any level.

País:
United States
Língua:
English
Editora:
Kalmbach Publishing Co. - Magazines
Periodicidade:
Monthly
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ASSINATURA
US$ 42,99
12 Edições

nesta edição

2 minutos
2014 stories that made an impact

E ach year, the editors of Astronomy are excited to bring you a new rendition of our “top 10 space stories” feature, this year once again written by Liz Kruesi, our contributing editor. The past year has been a dynamic one in astronomy, astrophysics, and cosmology, as this big story proves (p. 24). The discoveries and realizations this year were as exciting as ever. We have two important studies about cosmic dust in the solar system and the Milky Way that clarify how dust forms — from the explosions of supernovae scattered throughout the galaxy. Astronomers also measured the distance to some remote galaxies at high precision, helping further nail down the cosmic distance scale. Closer to home, planetary scientists discovered a subsurface ocean on Enceladus, the watery moon of Saturn, which…

1 minutos
the first stargazers

Some 7 million years ago, a group of creatures made their way across the plains of central Africa. Resembling a collection of savannah baboons, the 30 or so beings shuffled along as dusk began to fall over a clearing in what we now call Chad. Adult females and flocks of offspring made up the nucleus of this foray, with a few mature males following up and looking for mating opportunities. As darkness began to fall, the group approached a cave that held a common shelter, and light from the Moon blazed down onto what now appeared like black, slumped forms — dirty, disheveled, hairy, and marked by spots of blood from the day’s successful hunt. These earliest human beings, perhaps Sahelanthropus, were the first bipedals and walked more or less upright.…

1 minutos
distant cousins

In space, neighbors are not always what they seem. Take this pair of star-forming regions in the southern constellation Carina the Keel. Both glow with a reddish hue as hot young stars in their centers pump out ultraviolet radiation that excites surrounding clouds of hydrogen gas. But emission nebula NGC 3576 (top) lies only 9,000 light-years from Earth, while star cluster NGC 3603 and its gaseous cocoon (bottom) reside 20,000 light-years away. NGC 3603 has the highest concentration of heavyweight stars known in the Milky Way, and its hydrogen envelope is our galaxy’s most massive.…

4 minutos
crazy inferior worlds

T he inferior planets, Venus and Mercury, will be anything but the second week of January. Venus had a crummy 2014, but it’s now returning with a vengeance. Look west 40 minutes after sunset for two “stars” near the horizon. The brighter is Venus, on the left. The other is Mercury. From the 8th to the 13th, they’ll hover strikingly close to each other. They’re the only planets with no moons. The only ones that barely spin — needing months to rotate. (Every other planet’s day is less than 25 hours.) The only planets that can appear as crescents. The only ones with high densities similar to our world. These are intriguing resemblances. But here’s what’s weird. In most other areas, they’re not merely dissimilar, but oddly opposite. Venus’ surface sits under more air…

1 minutos
from our inbox

Black holes clarification Kudos to Bob Berman for the interesting article “Why everything you know about black holes might be wrong” in the October issue. However, I believe that one of the “myths” that he highlighted is actually true. Objects behind an event horizon cannot escape, regardless how they arrived there or the power of their engines. An observer who escaped from that region would see himself or herself outrunning light beams, an impossibility according to Einstein. — William Nelson, Tucson, Arizona It’s a common misconception that nothing can escape from within an event horizon. Certainly light cannot. But that is a boundary only for objects traveling naturally, like photons or infalling bits of star stuff. It does not apply to an object like a rocket that can apply acceleration. A rocket could…

2 minutos
hints of dark matter seen

The things we think of as the universe — planets, stars, galaxies — are actually just a small fraction of its total mass. Galaxies spin too fast and move too quickly in clusters, implying a majority of mass is lurking unseen, perhaps as dark matter. Except no one’s ever detected it. Until now, possibly. Earth’s atmosphere blocks out many high-energy particles, pushing physicists to space to search. It took 500 scientists some $2 billion and 16 years to get the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station and into the hunt for dark matter. And it gave early hints of a major payoff in September. The results were presented at CERN, the European Organization for Nuclear Research, on September 21 and published in the journal Physical Review Letters. It’s an…