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Astronomy

Astronomy March 2017

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
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US$ 42,99
12 Edições

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2 minutos
story of a supernova

Thirty years ago, a massive star exploded in a nearby galaxy, the Large Magellanic Cloud. What followed over weeks, beginning February 24, 1987, was a naked-eye object visible in the Southern Hemisphere, the dazzlingly brilliant light from a star torn asunder. Supernova 1987A peaked in brightness at magnitude 2.9 in May 1987 and became the brightest of its class since 1604, when Kepler’s Star beamed forth at –3 magnitude. Because it was the closest supernova in modern astronomical history, the star was studied incredibly thoroughly, and helped astronomers understand supernovae better than they ever had before. At a distance of 168,000 light-years, within the LMC, Supernova 1987A was not the next Milky Way supernova, the Holy Grail that some stellar astronomers seek. A Milky Way supernova could be hundreds or thousands of…

2 minutos
a universe with 10 times more galaxies

HOT BYTES >> TRENDING TO THE TOP EVERYTHING YOU NEED TO KNOW ABOUT THE UNIVERSE THIS MONTH . . . BOOM OR BUST The Chicxulub impact in Mexico may have been ground zero for dino-deaths, but it may also have sheltered smaller mammalian life. UP, UP, AND AWAY The GOES-R satellite launched November 19 into geostationary orbit to study weather on Earth and provide better forecasting. JUST ONE LOOK A group called Project Blue hopes to directly image a planet around Alpha Centauri A or B. To date, no such planet has been confirmed. The year 2016 was a big one for astronomical news. Following gravitational waves, a planet orbiting Proxima Centauri, and more, came news that the estimated number of galaxies in the cosmos may have been woefully low. Years ago, astronomers studied the Hubble Deep Field and extrapolated…

3 minutos
astroletters

A sizable victory I really enjoyed the article “Sizing up Space Rocks” by Michael Carroll in the November issue (p. 30). I’m an engineer, and I usually can estimate (and imagine) sizes of things in both systems of units, English and SI, but it is only after reading this story that I could truly appreciate the size of comets and asteroids. Before this, saying that an asteroid 160 feet across crashed into the Arizona desert never really struck a chord with me. Carroll’s cleverly scaled photograph of two asteroids superimposed on a sports stadium was revealing enough, but the photo on the next page of Comet Hartley in scale with the Eiffel Tower really blew my mind! The last photo of an assortment of known asteroids and comets on a “tablecloth”…

4 minutos
going for gold

As we reach Oscar time — late February or early March — the lessons of Hollywood come to mind. We did a big article on this some 20 years ago and felt honored to get praise from famed comet hunter David Levy and others. So let’s go there again, with some new suggestions. The idea is simple. Most backyard astronomers excitedly show their favorite celestial wonders to family, friends or even visiting school groups. It’s memorable for everyone, and it promotes astronomy. Our issue: Can you improve your telescope “show” so that your visitors are even more turned on to science? If so, it could change young minds and perhaps launch a lifelong hobby, or even a career choice. School kids don’t get telescope tours very often. This might be the…

1 minutos
‘pumpkin stars’ carve out a niche in the universe

Not all objects are created equally round. Recent observations by NASA’s Kepler and Swift space observatories found 18 stars that have taken on the name “pumpkin stars,” thanks to their unusual shapes. The findings were published October 25 in The Astrophysical Journal. As it turns out, pumpkin stars take on their oblong shape because of their shortperiods of rotation. On average, one of these stars rotates on its axis every 5.5 days. (By comparison, the Sun rotates every 24.5 days.) The process creates brilliant X-ray emissions far outstripping the Sun’s. At the same time, this rapid spinning affects the shape of the star, causing it to bulge at the equator. Most of the stars are between 2.5 and 10 times the size of the Sun. Most also seem to be entering their…

1 minutos
three degrees of separation

JIGSAW CONSTELLATIONS. You’ve heard of six degrees of separation, the theory that everyone on Earth can be connected to anyone else through no more than five intermediaries. Well, how many constellations do you have to traverse to link with one that the ecliptic passes through? Thirteen constellations contain a segment of the ecliptic, 35 lie one constellation away, 31 are separated by two star groups, and just nine have three degrees of separation. The closest of these to the celestial equator is Columba, which has multiple paths to either Gemini or Taurus. FAST FACT Of the nine constellations that require three hops from the ecliptic, only two — Cepheus and Ursa Minor — lie in the northern sky.…