Astronomy October 2019

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.

United States
Kalmbach Publishing Co. - Magazines
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12 Issues

in this issue

3 min.
it’s elemental

As astronomy enthusiasts, we’re most often focused on astronomy, astrophysics, planetary science, or cosmology. But I’d like you to stop for a moment and think about chemistry. Consider the very stuff you’re made from, for example. The average human has 7 octillion atoms in their body. That’s 10 to the 27th power. Put another way, it’s 7 billion billion billion atoms. Suffice to say, it’s a lot. These very same atoms were created in the early stages of the universe or in the bellies of exploding stars long ago. As the great astronomer Carl Sagan said, “The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.” Right now,…

2 min.
astro letters

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 clarity. Memories from The Outer Limits Michael Bakich’s article “The Outer Limits Universe” in the June 2019 issue brought back memories of what I consider the best television show of all time. I still remember watching that very first episode in September 1963. As the credits rolled, the combination of the haunting musical score and the beautiful astronomical photos (especially M104) always made me think of what could be out there. —Robert Lindner, Oak Creek, WI Another eclipse perspective “Ask Astro” in the June 2019 issue posed the question of how a full eclipse of the Sun would differ from the vantage point…

1 min.
a wispy treasure

The irregular galaxy IC 10 doesn’t need stunning spiral arms to show off. IC 10 is part of our Local Group of galaxies, of which the Andromeda Galaxy and the Milky Way are the largest members. And at only 2.2 million light-years away, this nearby neighbor is lighting up with a flurry of star formation, thanks to its ample reservoirs of cool hydrogen gas that collapse to form new suns. But despite its internal fireworks, IC 10 is faint, and wasn’t identified by astronomers until 1887. Even with modern instruments, it is challenging for astronomers to study because of its location in our sky, behind the dust and stars of our own galaxy. NASA, ESA AND F. BAUER.…

1 min.
hot bytes

REWRITING HISTORY A Texas State University astronomer determined that on June 5, 1944, the Moon rose before sunset and was visible all night. The finding corrects an oft-repeated but erroneous account that the Moon rose late the night before the D-Day invasion. RECENT ACTIVITY Researchers found signs of ammonia — which can’t last long on Pluto — in the redcolored, ditchlike Virgil Fossae, indicating cryovolcanoes erupted there within the last few million years. DOUBLE VISION The European Southern Observatory’s SPHERE instrument caught a stunning glimpse of the double asteroid 1999 KW4 on May 25, 2019, when the pair passed Earth at a mere 14 times the distance of the Moon. ARMY SIGNAL CORPS COLLECTION IN THE U.S. NATIONAL ARCHIVES…

3 min.
scientists read the sun’s history from moon rocks

As Sun-like stars mature, their rotation tends to slow. But when these stars are young, they rotate more quickly and less predictably. Two stars of the same mass may rotate at drastically different speeds. And stars that are fast rotators tend to hurl more powerful radiation and charged particles into their systems, often to the detriment of their planets. Without other clues, learning how fast the Sun once spun is difficult. But researchers led by Prabal Saxena of NASA’s Goddard Space Flight Center published a study May 3 in The Astrophysical Journal Letters that used lunar samples to determine how fast our Sun may have rotated in its early years, a factor that helped to determine how the inner planets, including Earth, evolved. SOLAR BLAST “After a billion years,” Saxena tells Astronomy, “[stars…

1 min.
quick takes

END OF AN ERA NASA’s Spitzer Space Telescope, launched in 2003 to study the infrared sky, will be permanently retired January 30, 2020. METEOR CLOUDS Vaporized space rocks can kickstart cloud formation on Mars, new research finds. Because ancient Mars was pummeled by meteorites, the discovery has implications for the Red Planet’s past water cycle. RING IT IN ALMA spotted a never-beforeseen ring of cool hydrogen gas wrapped around the Milky Way’s central supermassive black hole, providing fresh insight into how black holes accrete matter. WRECKING BALL A ball of dark matter may have plowed through a line of stars streaming around the Milky Way, disrupting them. If confirmed, this suggests dark matter is “cold,” meaning it’s heavy, relatively slow moving, and clumps together. MYSTERIOUS MASS Scientists have discovered an enormous mass of dense material, possibly the remains of…