Astronomy July 2018

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

2 min.
fun with black holes

Did you know that if Earth were squeezed down into the size of a grape, it would become a black hole? It’s true. Once thought to be merely hypothetical, or rare, black holes are now believed to exist in the universe in the trillions. In fact, most every normal galaxy — those more massive than dwarfs — harbors a black hole in its center, our Milky Way included. One of the more intriguing concepts associated with black holes is the so-called information paradox. When we combine two tenets of physics — quantum mechanics and general relativity — a conundrum arises regarding black holes. Mathematics suggests that physical information could disappear permanently into a black hole, and this would mean that many physical states in the universe could evolve into one state.…

4 min.
astro letters

The thrill of New Horizons Thank you for the article “New Horizons explores the Kuiper Belt” by S. Alan Stern in your February 2018 issue. It was so well written and had such detailing of the mission that I can already feel the excitement building. Please follow this mission closely and keep us informed. — Charles Martin, The Villages, FL The astro-jazz genre I’m very familiar with the song “Stars Fell on Alabama,” but I didn’t know that it was about the 1833 Leonid meteor shower until I read “The real music of the spheres” in the January 2018 issue. It had me going back to listen to the Byrds’ song “C.T.A.-102,” which I’m listening to as I write this letter. I enjoyed the article very much, but it has a glaring omission of…

1 min.
call me steve

Purple is not a common color for the aurora borealis. But reports of a strange, ribbonlike purple feature accompanying aurorae in 2015 and 2016 led astronomers to develop the Aurorasaurus citizen science project to unravel the beautiful mystery. The phenomenon, given the name Steve, is generated when charged particles from the solar wind encounter Earth’s magnetic field, just like the aurora. But Steve occurs specifically when fast-moving, hot particles stream along magnetic field lines close to the equator, causing it to appear at lower latitudes than the traditional aurora. The key to unlocking Steve’s nature was a combination of ground- and space-based images, which provide vital information about the phenomenon but can be hard to obtain, as Steve typically lasts only 20 minutes to an hour. Scientists now believe Steve (now officially STEVE:…

3 min.
small magellanic cloud is losing cosmic fight

The Large and Small Magellanic Clouds are the Milky Way’s largest satellite galaxies — and they’re locked in a cosmic game of tug-of-war. Though these dwarf galaxies orbit the larger Milky Way, they also orbit each other, exerting gravitational influence that has ousted a huge cloud of gas from one of the two. Using the Hubble Space Telescope (HST), astronomers have finally determined that the Small Magellanic Cloud is the losing party in this battle. The results, published February 21 in The Astrophysical Journal, examine a structure called the Leading Arm. The Magellanic Stream, which is an extended “tail” of gas, visible at radio wavelengths, that trails the two dwarf galaxies, was found in 2013 to contain gas mixed from both the Large and Small Magellanic Clouds. But, astronomers had wondered,…

1 min.
mercury’s southern exposure

PICTURESQUE POLE STAR. If you stood in one of the permanently shadowed craters at Mercury’s south pole and looked overhead, these are the stars you would see. The innermost planet’s axis points toward a rather bland part of the sky in the constellation Pictor the Painter. The only naked-eye star that lies within 1° of the pole is magnitude 3.3 Alpha (α) Pictoris. FAST FACT The sky’s second-brightest star, magnitude –0.7 Canopus, lies just 9° from Mercury’s South Celestial Pole.…

2 min.
stellar flyby shook up outer solar system

About 70,000 years ago, a small star passed within a light-year of the Sun, skimming the edge of the Oort Cloud — the extended shell of over a trillion icy objects that cocoons the outer solar system. Previously, astronomers believed this wandering star, dubbed Scholz’s star, passed by relatively peacefully, influencing few, if any, outer solar system objects. But new research suggests the star may have caused more of a ruckus than we thought. In a study published February 6 in Monthly Notices of the Royal Astronomical Society: Letters, scientists analyzed the orbital evolution of 339 known minor objects (like asteroids and comets) with hyperbolic orbits that will eventually usher them out of the solar system. By winding their orbits back 100,000 years, the team was able to estimate the point in…