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SKY & TELESCOPESKY & TELESCOPE

SKY & TELESCOPE

July 2019

Since the first issue was published in 1941, Sky & Telescope has become the go-to resource for all things star and space. This magazine is considered the complete resource for the astronomy enthusiast. Offering everything from product reviews, buyer's recommendations, and current events news to tips, how-to articles, and computer software, fascinated readers will find a wealth of information and suggestions on how to hone their hobby. Devoted amateurs, professionals, and academics would all find a subscription to Sky & Telescope magazine of interest.

Pays:
United States
Langue:
English
Éditeur:
F+W Media, Inc. - Magazines
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12 Numéros

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access_time2 min.
a night to remember

(SEAN WALKER / S&T)WHEN I WAS NINE YEARS OLD, my parents dragged me out of bed one night around 10:30 p.m. and led me to the living room. I’m guessing they also rousted my brother and sister, but I don’t remember them. All I recall is sitting in my pajamas on the rug against the sofa and rubbing sleep from my eyes as I tried to focus on grainy images playing across our small black-and-white TV set.It was July 20, 1969.To this day I thank my parents for ensuring I didn’t miss those historic first human steps on the Moon. The next morning I asked if I could keep that day’s New York Times. Fifty years later, as we started preparing this special Moon issue in honor of Apollo 11’s…

access_time6 min.
all our fault

Ever since you published Kelly Beatty’s cover story “Where Are the Young Astronomers?” (S&T: Sept. 2000, p. 82), that article has haunted me.The Crewe Astronomy Club was founded in 1998, and as many other clubs do, we brought out our telescopes and explained the night sky to the general public at five Virginia state parks. But since September 2000, we altered the course of our programs to let children have a hands-on approach to discovering the night sky. We stopped bringing the fancier telescopes — equatorial, tracking, Go To — and brought 12 smaller refractors, reflectors, and several Dobsonians that kids could operate and let them have control. My wife and I also built an observatory and science center in our barn so kids could come to our 30-acre farm…

access_time2 min.
75, 50 & 25 years ago

1944July 1944Lunar Atmosphere? “Walter H. Haas, of Upper Darby, Pa., writes: ‘The occultation of Jupiter by the moon on April 30th – May 1st was observed with the 18-inch refractor of the Flower Observatory, using 150×…. When the planet emerged from behind the bright limb of the moon, a hazy gray band concentric with the lunar limb was seen across the face of Jupiter. The angular width of the band was estimated to be three seconds of arc.“‘I am greatly interested in this marking because of the interpretation that W. H. Pickering put upon it [in an 1892 article:] ‘The Lunar Atmosphere and the Recent Occultation of Jupiter.’ …’”A keen observer, Walter Haas later founded the Association of Lunar and Planetary Observers. But what had he seen? The Moon’s atmosphere…

access_time3 min.
ryugu vs. bennu: updates from the asteroids

Particles spewed from Bennu on January 19th.SCIENTISTS WITH NASA’S Osiris-REX and the Japan Aerospace Exploration Agency’s Hayabusa 2 spacecraft provided preliminary results at the annual Lunar and Planetary Science Conference regarding their respective explorations of near-Earth asteroids 101955 Bennu and 162173 Ryugu. A slew of papers in Nature, Nature Astronomy, Nature Geoscience, and Science accompanied the presentations.Except for size, Bennu and Ryugu are hard to tell apart in photos. Both are so-called “rubble piles,” collections of debris weakly bound by gravity. Their low densities imply Swiss-cheese interiors. On the surface, both terrains are dark (reflecting about 4.5% of incident sunlight) and strewn with large boulders. And, despite being around for more than 100 million years, both bodies have few small craters, suggesting that something — perhaps shaking from bigger impacts…

access_time2 min.
is there methane on mars?

TWO STUDIES ARE FINDING conflicting results about whether methane exists on Mars. Its presence would point to certain geochemical processes or, less likely, biological activity.Researchers using the Planetary Fourier Spectrometer (PFS) aboard Europe’s Mars Express orbiter spotted 15.5 parts per billion by volume (ppbv) of methane in 2013, a day after NASA’s Curiosity rover measured a spike of 5.78 ppbv. Atmospheric simulations and geological analysis helped track the emission’s origin to a fault area southeast of Gale Crater, Marco Giuranna (National Institute of Astrophysics, Italy) and colleagues report April 1st in Nature Geoscience.However, the European-Russian ExoMars Trace Gas Orbiter (TGO), a spacecraft designed to measure vanishingly small amounts of gases in the carbon dioxide–based atmosphere, has failed to find any methane during the first months of its science operations. The…

access_time2 min.
could dark matter be black holes?

NEW OBSERVATIONS LIMIT the role that primordial black holes can play in explaining dark matter.Even before there were stars, primordial black holes (PBHs) could have been born when patches of the radiation and plasma that filled the early universe became sufficiently dense to collapse into black holes. Astronomers have looked for PBHs using microlensing: When a black hole passes in front of a more distant star, its gravity bends the star’s light toward us, boosting its brightness. No PBHs have been definitively detected yet.As part of ongoing efforts, Hiroko Niikura (University of Tokyo) and colleagues turned the 8.2-meter Subaru Telescope’s Hyper Suprime-Cam on an estimated 100 million stars in the Andromeda Galaxy. The galaxy is far enough away that each camera pixel contained the light from several suns, so the…

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