Astronomy July 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.

United States
Kalmbach Publishing Co. - Magazines
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12 Issues

in this issue

2 min.
where has all the water gone?

Long ago, on a planet not so far away, water flowed abundantly. That’s the Red Planet, Mars, long a source of speculation about life outside Earth. As spacecraft have explored Mars in ever-greater detail, they’ve accumulated growing evidence that water was once abundant on our celestial neighbor. But signs of water flowing on the martian surface today are scarce. They are shown in the accompanying image. It depicts dark streaks caused by seeping flows of briny water down the walls of a crater called Garni. In her feature story this month, planetary scientist Tanya Harrison reveals the history of water on Mars. In what astronomers call the Noachian Era, between 4.1 billion and 3.7 billion years ago, water flowed abundantly on the planet. Most scientists believe that during the first billion years…

2 min.
a system of seven worlds

EVERYTHING YOU NEED TO KNOW ABOUT THE UNIVERSE THIS MONTH . . . SNAPSHOT HOT BYTES >> TRENDING TO THE TOP TARGET: VENUS NASA and a group of Russian scientists met to discuss science objectives for the Venera-D mission, a return to Venus featuring an orbiter and lander. CLIPPER SHIP NASA’s Europa mission has been officially designated the Europa Clipper, an informal name used during the mission’s development. MOON TRIP SpaceX will take two tourists on a quick loop around the Moon in 2018, for an undisclosed price. In February, NASA held a special news conference for an amazing announcement: A team of scientists described the discovery of the first known system of seven Earthsized worlds orbiting one star. The system, called TRAPPIST-1, was named for the small telescope in Chile used for the discovery. The planets orbit an ultra-cool dwarf…

4 min.
moon motion

The great eclipse is getting close now. I hope you will not stay put and be content with a mere partial event, but will travel to witness the unbelievable majesty of totality. One often-neglected aspect of the spectacle involves motion. This is more singular and special than popularly realized. That’s because a frozen visual scene is the norm in our profession or hobby. When we look through telescopes, it’s a slide show. The images are static. Nothing moves. We’re used to it. The entire human race will come and go before the great globular cluster in Hercules looks any different. Even much closer to home at 410 lightyears, the beautiful colored double star Albireo has not changed since the first telescopes were aimed its way in the 17th century. We know the…

2 min.
astro letters

Trick of the light Regarding Stephen James O’Meara’s article “Twice-setting stars” in the March 2017 issue: When I lived along the Lake Michigan shoreline in my youth, it was fairly common to see inferior mirages of ships going over the horizon, but always later in the summer, which lends credence to the idea that a layer of moist, warm air over cooler waters creates this illusion. I have also seen lights over the lake in the early evening coming from Ludington, Michigan, which is directly across from Manitowoc, Wisconsin, where I lived. Ludington is completely over the horizon from Manitowoc, so the same effect must have occurred for these lights to be visible. People have also reported these sightings at night on the car ferry, which still runs between the two…

2 min.
can tons of xenon finally find dark matter?

A dark matter experiment located deep underground will soon provide the means to find elusive axions, a type of hypothetical elementary particle. The project, called LUX-ZEPLIN, will be built at the Sanford Underground Research Facility, an abandoned gold mine in rural South Dakota. At that location, 1 mile below the surface, cosmic rays can’t interfere with potential detections of dark matter. While 23 percent of the universe is believed to consist of dark matter — a type of matter initially theorized to explain discrepancies in the observed rotation rates of galaxies when compared with the rotation astronomers expected — scientists aren’t exactly sure what dark matter is made of. Although there are several competing ideas, the two most popular scenarios are massive compact halo objects (MACHOs) and weakly interacting massive particles (WIMPs). The…

1 min.

HIDDEN STAR FORMATION Astronomers at the University of Massachusetts Amherst uncovered a high rate of star formation in a distant galaxy using the Large Millimeter Telescope. As much as 75 percent of this galaxy’s star formation is hidden from optical telescopes by dust. Star formation in young galaxies is the precursor of the materials that form stars and planets in the local universe. Because this galaxy appears typical, a high rate of hidden star formation and dust production could change the way astronomers view these processes. RESURRECTING ASTROPHOTOS Astronomy Rewind is a citizen science project launched on March 22 to give new life to old images from the pages of astronomical journals. The project will resurrect “zombie” photos, charts, and maps scanned from paper publications by incorporating them into digital sky catalogs, where…