Skywatching Archives

October 6, 2023October 6, 2023 by Evan Gough

One of the Brightest Stars in the Sky is Actually a Satellite

The bright streaks drawing an arc across the night sky are caused by the satellite BlueWalker 3. The prototype satellite is brighter than most stars. Image Credit: Ilse Plauchu-Frayn

Back in the 70s, kids used to look up at the summer sky and try to be the first one to shout, “Satellite!” That seems like a relic from the past now, alongside Polaroid cameras and astronauts on the Moon. These days, it’s rare to spend any amount of time looking at the sky without seeing a satellite, or several of them.

A new satellite is emphasizing that fact. It’s a prototype communications satellite with a roughly 700-square-foot antenna, and it’s brighter than most stars.

January 20, 2023January 20, 2023 by Evan Gough

Light Pollution is Obscuring the Night Sky. RIP Stargazing

A startling analysis from Globe at Night — a citizen science program run by NSF’s NOIRLab — concludes that stars are disappearing from human sight at an astonishing rate. Image Credit: NOIRLab/NSF/AURA, P. Marenfeld

A citizen science initiative called Globe at Night has some sobering news for humanity. Our artificial light is drowning out the night sky for more and more people. And it’s happening more rapidly than thought.

January 18, 2022January 18, 2022 by Brian Koberlein

20% of Twilight Observations Contain Satellite Passes

Starlink trails and a meteor as seen from Brazil. Credit: Egon Filter

With the rapid expansion of commercial space, there is a growing number of satellites in orbit around our planet. Most of these are in low-Earth orbit, which is becoming increasingly crowded. This has led some to be concerned about a catastrophic rise of space debris, as well as a growing frustration by astronomers due to the number of satellite sky trails.

December 14, 2021December 14, 2021 by Paul M. Sutter

Astronomy Jargon 101: Absolute Magnitude

Taken with the HAWK-I instrument on ESO’s Very Large Telescope in the Chilean Atacama Desert, this stunning image shows the Milky Way’s central region with an angular resolution of 0.2 arcseconds. This means the level of detail picked up by HAWK-I is roughly equivalent to seeing a football (soccer ball) in Zurich from Munich, where ESO’s headquarters are located. The image combines observations in three different wavelength bands. The team used the broadband filters J (centred at 1250 nanometres, in blue), H (centred at 1635 nanometres, in green), and Ks (centred at 2150 nanometres, in red), to cover the near infrared region of the electromagnetic spectrum. By observing in this range of wavelengths, HAWK-I can peer through the dust, allowing it to see certain stars in the central region of our galaxy that would otherwise be hidden.

In this series we are exploring the weird and wonderful world of astronomy jargon! You’ll surely measure the awesomeness of today’s topic: absolute magnitude!

September 20, 2021September 20, 2021 by Evan Gough

How Could we Light our Cities and Still See the Night Sky?

Standing beside the Milky Way. Drowing out the night sky blocks us off from nature, and that's not good for humans. Credit: P. Horálek/ESO

The night sky is a part of humanity’s natural heritage. Gazing up at the heavens is a unifying act, performed by almost every human that’s ever lived. Haven’t you looked up at the night sky and felt it ignite your sense of wonder?

But you can’t see much night sky in a modern city. And the majority of humans live in cities now. How can we regain our heritage? Can quiet contemplation make a comeback?

November 9, 2020November 8, 2020 by Paul M. Sutter

Most light pollution isn’t coming from streetlights

Zodiacal light tilts upward from the western horizon and points at the Pleiades star cluster in this photo taken March 19, 2009. Clouds at bottom reflect light pollution from nearby Duluth, Minn. U.S. Credit: Bob King

Light pollution is the arch nemesis of astronomy, spoiling both the enjoyment of the night sky and the professional study of our universe. For years we’ve assumed that streetlights are the main culprit behind light pollution, but a recent study has shown that streetlights contribute no more than 20% of all the pollution, and if we want to solve this vexing astronomical problem, we have to think harder.

December 26, 2018December 26, 2018 by David Dickinson

Top Astronomy Events For 2019

Transit of Mercury — The May 9th, 2016 transit of Mercury. Image credit and copyright: Steve Knight.

You might’ve heard the news. We wrote a book this past year: The Universe Today’s Ultimate Guide to Observing the Cosmos: Everything You Need to Know to Become an Amateur Astronomer. Judging from reader feedback thus far, one of the most popular parts of the book is Chapter 10, where we list the top astronomical events by year for the coming six years. True story… we picked six (2019 to 2024) to stretch out the list to touch on the April 8^th, 2024 total solar eclipse. Continue reading “Top Astronomy Events For 2019”

December 12, 2018December 12, 2018 by David Dickinson

Get Ready for the 2018 Geminid Meteors

2018 Geminids — A timelapse of the 2017 Geminids, taken from the Chiricahua Mountains in southern Arizona. Image credit and copyright: Alan Dyer/AmazingSky.com

When it comes to meteor showers, the calendar year always seems to save the best for last. We’re referring to the Geminid meteor shower, one of the sure fire bets for dependable meteor showers. In fact, in recent years, the Geminids have been upstaging that other yearly favorite: the August Perseids. If the Geminids did not occur in the chilly (for the northern hemisphere) month of December, they’d most likely get a better rap. Continue reading “Get Ready for the 2018 Geminid Meteors”

December 6, 2018December 10, 2018 by David Dickinson

On the Astronomy Trail in Nebraska

It’s a never-ending quest for observers, lovers of the night sky and astrophotographers. Where to go to get away from encroaching light pollution, and find truly dark skies?

Most of us think of distant sites such as Death Valley, the Kalahari Desert or the Canary Islands when it comes to dark skies. And while it’s true that many observers are now traveling farther and farther away from home in search of truly dark skies, that trip need not be as far as you think.

We had the opportunity to visit one such often overlooked dark sky gem: the state of Nebraska. From fossils to aeronautics and astronomy, there’s lots of science to explore in the Cornhusker State. Though the state has a rich science heritage, and an active amatuer astronomy community, Nebraska is an often overlooked dark sky haven. But science tourism is also becoming increasingly popular, and Nebraska has lots to offer.
Continue reading “On the Astronomy Trail in Nebraska”

November 30, 2018November 30, 2018 by David Dickinson

A 2018 Outburst From the December Andromedids?

A relatively obscure meteor shower may put on a surprise performance in early December 2018. Chances are, you’ve never heard of the Andromedids, though it’s worth keeping an eye out for these swift-moving meteors over the next week. Continue reading “A 2018 Outburst From the December Andromedids?”