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Astronomy

Astronomy September 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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US$ 42,99
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2 minutos
the breathtaking pace of science

Before last year, a little piece of our knowledge of the cosmos was completely different. In the collective history of humans studying the universe around us, we had looked up close at a comet only a few times — with relatively fleeting glances and not with the kind of resolution we now have. And then came Rosetta’s rendezvous with Comet 67P/Churyumov-Gerasimenko. In August 2014, the spacecraft arrived at this periodic comet, commencing a series of maneuvers that swung it along triangular paths, staying around 30 to 60 miles (50 to 100 kilometers) from the comet’s 3-mile-wide (5km) nucleus. Last November, the spacecraft detached its Philae lander, which touched down and transmitted the first detailed pictures from the surface of a comet’s nucleus. After some 60 hours of operations, the lander shut down,…

1 minutos
part-time believers not needed

I’ve been fascinated by the landscape of social media posts lately. Astronomy enthusiasts are a smart bunch, but even many of those who are experienced in the details of the science seem to believe in a blend of science and science fiction. “Why couldn’t we travel across the galaxy?” (Answer: Maybe we could, but the evidence — laws of matter and mass and relativity and gravitation — suggests it would be difficult, if not impossible, regardless of technological advances.) “Why can’t you travel through black holes?” (Answer: They would shred you into a string — stellar black holes at least — and therefore the whole travel idea becomes irrelevant.) This amalgam of science and science fiction that dominates so many people’s minds intrigues me. To many, what is perceived as science is really…

4 minutos
september eclipse oddities

It’s not often that nearly the whole Western Hemisphere sees a total lunar eclipse. It won’t happen again until 2019. Plus, this September 27 event is in prime time; no one has to set an alarm. Only folks in Alaska and Hawaii miss totality. Let’s focus on the oft-neglected oddities. The noticeable part of the eclipse begins at 9:07 p.m. EDT when the left side of the Moon first encounters our planet’s dark inner shadow, the umbra. The next 15 minutes offer a Dali-esque surrealism. The black chunk taken out of the Moon’s edge leaves the remaining lunar disk a bizarre shape that cannot be mistaken for any normal lunar phase. Even though Earth’s umbral shadow tapers like a chopstick to only about half its original size at the Moon’s distance, that’s still…

2 minutos
from our inbox

Spooky shadow I am thankful for Stephen James O’Meara’s May 2015 column (p. 14) about the spooky shadow effect. I have seen the effect many times and have wondered what was the explanation for it. Beside my bed is a small lamp with a thin black cord. When I lie in bed looking at the cord from approximately 200 millimeters away and point at the cord at half that distance, it looks like when my finger seems to touch the cord, the cord jumps onto my finger! It’s always a pleasure reading O’Meara’s column. — Bent Pedersen, Stenlille, Denmark We welcome your comments at Astronomy Letters, P. O. Box 1612, Waukesha, WI 53187; or email to letters@astronomy.com. Please include your name, city, state, and country. Letters may be edited for space and…

2 minutos
rapid changes on a super-earth

Nearby super-Earth 55 Cancri e is a dynamic place — not to mention inhospitable. This planet — twice the radius of Earth and eight times as massive — whirls around its star once every 18 hours and is tidally locked so that one side always faces the broiling sun and the other the cold of space. In the span of two years, astronomers have seen the planet’s dayside temperature swing from 1,800° to 4,900° F (1,000° to 2,700° C). It marks the first time scientists have been able to discern such clear variability on an exoplanet. The researchers need more analysis before they can be sure of the cause, but their current most likely theory involves massive volcanic eruptions that smother the world in gas and dust, blocking thermal emission…

1 minutos
briefcase

COSMIC BBQ GIVES HOT START TO LIFE DNA is the backbone of life on Earth. Explaining the double helix’s origin has consumed careers since James Watson and Francis Crick announced it in 1953. Researchers from Berkeley Lab and the University of Hawaii looked at its molecular precursors and found cosmic hot spots near dying carbon-rich stars are prime places to form these nitrogen-rich molecular rings, according to an April 20 Astrophysical Journal paper. HIGH SCHOOL TEAM FINDS STRANGE PULSAR Massive stars explode as supernovae when they die, with some leaving behind pulsars — rapidly spinning neutron stars that shoot radio waves in bright beams. Only a small number of those sit in binary star systems. And a teenage team found the widest known orbit of any such pulsar so far — once every…