Astronomy September 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
Read More
12 Issues

in this issue

2 min.
lure of the red planet

Ever since the first tales of “Martians” emerged in the 19th century, humans have been fascinated by our close planetary neighbor. While we have not found life on Mars, exploring the Red Planet has become a cottage industry. It accounts for about 60 percent of the recent planetary exploration budget. Why? Because life may exist there yet. Despite its extreme cold temperatures, Mars has ample stores of water, locked up as ice in the polar caps and believed to exist in subsurface aquifers. Perhaps life does exist on Mars — microbial life. This month’s cover story by planetary scientist Alfred McEwen highlights an active Mars mission, the Mars Reconnaissance Orbiter. Specifically, the story focuses on one of the spacecraft’s instruments, the HiRISE camera, which stands for High Resolution Imaging Science Experiment. This…

4 min.
astro letters

Pluto appreciation When I received the May 2018 issue, I went straight to the article “An organically grown planet definition” by Dr. Runyon and Dr. Stern. I want to thank them both for such a refreshing perspective. We really should be teaching everyone, students and adults alike, “the types and subtypes of planets and how the solar system is naturally organized outward from the Sun, using a handful of planets as examples.” While I wish I had the creative understanding to have arrived at this conclusion myself, that’s no matter because it’s clearly the right perspective for everyone to have. May we all appreciate the beauty of our solar system, and all types of planets everywhere, because of it! — Mike VanVooren, Ballwin, MO Squashing conspiracies I just couldn’t read Bob Berman’s article “Apathy Now!”…

1 min.
lava lamp

The Hawaiian islands’ youngest and most active volcano, Kīlauea, began a surge of activity in May. Located on the southeastern shore of the Big Island, the volcano has since destroyed hundreds of homes. A cloud-monitoring camera situated at the Gemini North 8-meter telescope atop Mauna Kea, more than 30 miles (50 kilometers) away from Kīlauea, captured light from the eruption May 21–22, as several fissures spewed lava and molten rock that flowed into the sea. In this image, taken from a longer time-lapse video, the bright glow of the volcano is visible above a sea of clouds and against a backdrop of stars. To the volcano’s left, the dimmer yellow glow comes from lights in the town of Hilo. The foreground landscape appears bright, thanks to illumination from the Moon. Gemini’s cloud-monitoring camera…

2 min.
the first interstellar immigrant

Less than a year ago, astronomers discovered ‘Oumuamua, the first object from another solar system ever seen passing through our own. Now, a new study published May 21 in the Monthly Notices of the Royal Astronomical Society: Letters announces the discovery of the first known interstellar object to have taken up permanent residence around the Sun. Astronomers discovered the asteroid, which has the catchy name 2015 BZ509 (Bee-Zed for short), in 2015 using the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). The discoverers noticed Bee-Zed had a very peculiar yet stable orbit — it shares a nearly perfect 1-to-1 resonance with Jupiter but travels in the opposite direction — but they could not explain its retrograde motion. “How the asteroid came to move in this way while sharing Jupiter’s orbit has…

1 min.
the big dipper transformed

BEAR NECESSITIES. The brightest stars in the constellation Ursa Major the Great Bear form a distinctive asterism called the Big Dipper. But the stars won’t always be able to hold water. As they orbit the center of the Milky Way, these suns slowly change position in our sky. Although they resemble a familiar kitchen utensil today (left), the group will be unrecognizable in 100,000 years (right). FAST FACT Five Big Dipper members — Beta (β), Gamma (γ), Delta (δ), Epsilon (ε), and Zeta (ζ) Ursae Majoris — belong to the Ursa Major Moving Group and remain largely aligned.…

2 min.
ideas about star formation are challenged

The current picture of star formation is this: Within a dense cloud of gas and dust, perturbations cause localized areas to fragment into “cores.” These cores further fragment and collapse; when a region in the core reaches the conditions required for fusion, a star is born. Based on data from nearby star-forming regions, astronomers have long believed that the masses of the stars produced depend on the masses of the cores that develop. And in these nearby regions, cores and stars occur in a consistent pattern: Stars with masses similar to our Sun’s are common, but very high- and low-mass stars are rare. Astronomers had assumed this pattern of mass distribution occurred throughout our galaxy, in clouds of both high and low density. But new observations with the Atacama Large Millimeter/submillimeter Array…