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Astronomy

Astronomy April 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
hubble’s deep legacy

Twenty-five years ago, NASA launched what promised to be the world’s greatest astronomical instrument, the Hubble Space Telescope. And then, shocked and stunned when they found the optics to be flawed, engineers devised a way to fit Hubble with corrective lenses, transforming it into a machine that has rewritten our understanding of the cosmos. This special issue examines the legacy of the instrument that, in a span of 25 years, has contributed more revolutionary observations than any telescope that preceded it. It’s fitting that a quarter-century of groundbreaking science gives way to an examination of Hubble’s triumphs. Our package delivers some pretty good stuff. Astronomer Mario Livio writes about the greatest scientific discoveries made using Hubble. Science writer Ben Evans details the five servicing missions that repaired and then kept Hubble…

1 minutos
how the moon formed

SNAPSHOT When we walk outside at night and look skyward, it’s usually the Moon, our planet’s natural satellite, that first catches our eye. The fifth-largest moon in the solar system, the Moon is one of the largest in relation to its parent body. Called the Giant Impact Hypothesis, the accepted story of the Moon’s formation suggests that 4.6 billion years ago, two planets floated in the space now occupied by the Earth-Moon system. Proto-Earth had 50 to 90 percent of its current size and mass, and a Mars-sized planet also existed, one that astronomers now call Theia (in Greek mythology, mother of the Moon goddess Selene). Planetary scientists believe some 4.53 billion years ago, Theia struck Earth, creating a short-lived ring of debris that accreted into the Moon. The majority of Theia’s mass…

1 minutos
a party of fireflies

The southern constellation Carina holds some of the Milky Way’s most spectacular star clusters. Case in point: NGC 3532, also known as the Firefly Party Cluster and Wishing Well Cluster. Its hottest stars glow with a characteristic blue color, while the cooler red giants appear bright orange. This 300-millionyear-old cluster lies some 1,300 light-years from Earth. Astronomers captured this image through the European Southern Observatory’s 2.2-meter telescope at La Silla in Chile. NGC 3532 is an appropriate subject on the 25th anniversary of the Hubble Space Telescope’s April 1990 deployment because it was the orbiting observatory’s first target. ESO/G. BECCARI…

4 minutos
dark vs. super dark

Lecturing takes me to star parties around the U.S. It’s fun to see what excites backyard astronomers, and I feel honored to look through homebuilt telescopes. Yet interestingly, many of these gatherings are held under skies that are good — but not excellent. This isn’t a criticism. In three northeastern states, the most rural possible location is still within 30 miles (50 kilometers) of a city, producing bright glows in multiple directions. This is a central issue and battle cry for organizations like the International Dark-Sky Association, which tirelessly tries to limit waste lighting and unshielded yard lights. Since I also lead annual overseas trips to perfect sites in deserts and such, I’m keenly aware of the dark skies issue, to which we can all relate. Strangely enough, in all these years,…

2 minutos
from our inbox

Educating our youth While I always enjoy Astronomy magazine, the opening pages of the October issue, in particular, had an exceptionally welcome effect on me. “Separating fact and fiction” (p. 6) by Editor David J. Eicher was a genuine piece of visionary thinking! In my view, Eicher nailed a major dilemma of our modern culture and the goal toward which we should, and can, aspire. We do live in a society where “we are immersed in a constant stream of entertainment” and where both the younger and older generations celebrate “the trivial … not caring for the meaningful,” as he aptly puts it. But, indeed, we can overcome these tendencies by educating our youth to focus their energies on realizing “where we are and why we are here.” Eicher strikes a resonating chord…

2 minutos
voyager 1 experiences long-lasting shock wave

MASSIVE MERGER. Astronomers believe the massive stars in the binary MY Camelopardalis are orbiting so close to each other that they will soon merge into one massive sun. The find forwards a theory that the largest stars form this way. When the Voyager 1 spacecraft passed the realm of the planets and headed toward interstellar space, scientists couldn’t be sure what to expect. After all, this was a new frontier of space exploration. And according to the University of Iowa’s Don Gurnett, who presented new Voyager data December 15 at the American Geophysical Union meeting in San Francisco, the interstellar medium the spacecraft officially entered in 2012 has had its surprises. Since October 2012, Voyager 1 has experienced three “tsunami waves.” Such shock waves occur when a wave of pressure from a…