Astronomy Archives

January 9, 2023January 16, 2023 by David Dickinson

Comet E3 ZTF Brightens as the First Good Comet of 2023

The first good comet of the year, Comet E3 ZTF is a fine object for northern hemisphere observers in January.

As in years previous, 2023 kicks of with another decent binocular comet.

If you haven’t seen C/2022 E3 ZTF yet, you’ll soon have your chance. Discovered by the Zwicky Transient Survey searching for supernovae, E3 ZTF was first spotted as a +17^th magnitude object gliding through the constellation of Aquila the Eagle on the night of March 2^nd, 2022.

January 8, 2023January 8, 2023 by Scott Alan Johnston

New JWST Image Shows That Grand Spiral Galaxies had Already Formed 11 Billion Years ago

For the first time this week, photos from the James Webb Space Telescope (JWST) revealed that stellar bars were present in some galaxies as far back as 11 billion years ago. Stellar bars are a defining feature of about two-thirds of all spiral galaxies in the Universe, including our own Milky Way. The discovery has implications for astronomers’ understanding of galactic evolution, indicating that bars form very quickly and may persist for much of a galaxy’s lifespan, influencing its shape and structure.

January 7, 2023January 7, 2023 by Anton Pozdnyakov

Eruption on Io, Moon Navigation, Space-Based Power Test

NASA is looking for dangerous asteroids, Io is blasting lava into space, the solar wind could be creating water on the Moon, space power is finally getting a test.

January 5, 2023January 5, 2023 by Matt Williams

Wandering Stars Have Been Adrift Between Galaxies for Billions of Years

Hubble Space Telescope images of two massive clusters of galaxies named MOO J1014+0038 (left panel) and SPT-CL J2106-5844 (right panel).. Credits: NASA/ESA/STScI/James Jee (Yonsei University)/Joseph DePasquale (STScI)

In the giant galaxy clusters in the Universe, which can consist of hundreds or thousands of galaxies, there are countless “rogue” stars wandering between them. These stars are not gravitationally bound to any individual galaxy but to the halo of galaxy clusters themselves and are only discernible by the diffuse light they emit – “Ghost Light” or “Intracluster light” (ICL). For astronomers, the explanation for how these stars became so scattered throughout their galaxy clusters has always been an unresolved question.

There are several theories, including the possibility that the stars were pulled from their galaxies, ejected in the course of galactic mergers, or were part of their cluster since its early formation billions of years ago. Using NASA’s Hubble Space Telescope, a team from Yonsei University, Seoul, and the University of California, Davis, conducted an infrared survey of distant galaxy clusters. Their observations suggest that these wandering stars have been adrift for billions of years and were not stripped from their respective galaxies.

January 4, 2023January 4, 2023 by Scott Alan Johnston

Io is Having a Major Volcanic Outburst

Since last summer, Jupiter’s third largest moon, Io, has been lighting up the Jovian system with a major burst of volcanic activity. As the Solar System’s most volcanically active world, Io is no stranger to such outbursts, but this year’s display has been unusually energetic.

January 4, 2023January 4, 2023 by Evan Gough

How Many Stars Formed Together With the Sun in Our Stellar Nebula?

This is a two-panel mosaic of part of the Taurus Giant Molecular Cloud, the nearest active star-forming region to Earth. The darkest regions are where stars are being born. Inside these vast clouds, complex chemicals are also forming. Image Credit: Adam Block /Steward Observatory/University of Arizona

Even though our Sun is now a solitary star, it still has siblings somewhere in the Milky Way. Stars form in massive clouds of gas called Molecular Clouds. When the Sun formed about five billion years ago, other stars would’ve formed from the same cloud, creating a star cluster.

How many other stars formed in the cluster?

January 3, 2023January 3, 2023 by Matt Williams

Seen From Space: Sand Dunes on Mars Covered by Frost

This image acquired on July 22, 2022 by NASA's Mars Reconnaissance Orbiter shows sand dunes moving across the landscape. Winter frost covers the colder, north-facing half of each dune. Credit: NASA/JPL-Caltech/University of Arizona

It’s winter here on Earth, for those living in the northern hemisphere. This means snow, rain, colder temperatures, and all the other things we associate with “the festive season.” Much the same is true for Mars (aka. “Earth’s Twin”), which is also experiencing winter in its northern hemisphere right now. This means colder temperatures, especially around the polar regions where it can get as low as -123 °C (-190 °F), as well as ice, snow, frost, and the expansion of the polar ice caps – which are composed of both water ice and frozen carbon dioxide (“dry ice”).

While Mars does not experience snowfall the same way Earth does, seasonal change results in some very interesting phenomena. Thanks to the many robotic explorers NASA and other space agencies have sent to Mars in the past fifty years, scientists have been able to get a close-up look at these phenomena. These include the Viking orbiters and landers that studied the planet in the 1970s (with groundbreaking results) to the Mars Reconnaissance Orbiter (MRO), the Mars Exploration Rovers (Spirit and Opportunity), and the Curiosity and Perseverance rovers exploring the surface today.

December 26, 2022December 26, 2022 by David Dickinson

Astronomy 2023: Top Sky Watching Highlights for the Coming Year

Annular Eclipse — An annular eclipse from 2013. Credit: Shahrin Ahmad.

Astronomy 2023 highlights include two fine solar eclipses, the Sun heading towards solar maximum, a series of spectacular lunar occultations and much more.

Been out enjoying the sky in 2022? The past year saw two fine total lunar eclipses, a surprise meteor outburst from the Tau Herculids, a fine occultation of Mars by the Moon and more. Astronomy 2023 promises more of the same, plus much more. We’ve been doing this yearly roundup of things to look for in the sky now for well over a decade in one form or another, and the cosmos never disappoints. So, without further fanfare, here are the very best of the best events for astronomy 2023, coming to a sky near you:

December 24, 2022December 24, 2022 by Matt Williams

The Universe is Brighter Than we Thought

Artist's impression of NASA's New Horizons spacecraft. Credit: NASA/APL/SwRI and NASA/JPL-Caltech

Over seven years ago, the New Horizons mission made history when it became the first spacecraft to conduct a flyby of Pluto. In the leadup to this encounter, the spacecraft provided updated data and images of many objects in the inner and outer Solar System. Once beyond the orbit of Pluto and its moons, it embarked on a new mission: to make the first encounter with a Kuiper Belt Object (KBO). This historic flyby occurred about four years ago (Dec. 31st, 2015) when New Horizons zipped past Arrokoth (aka. 2014 MU69).

Now that it is passing through the Kuiper Belt, away from the light pollution of the inner Solar System, it has another lucrative mission: measuring the brightness of the Universe. These measurements will allow astronomers to make more accurate estimates of how many galaxies there are, which is still the subject of debate. According to new measurements by New Horizons, the light coming from stars beyond the Milky Way is two to three times brighter than the light from known populations of galaxies – meaning that there are even more out there than we thought!

December 23, 2022December 23, 2022 by Scott Alan Johnston

Is the Milky Way… Normal?

Studying the large-scale structure of our galaxy isn’t easy. We don’t have a clear view of the Milky Way’s shape and features like we do of other galaxies, largely because we live within it. But we do have some advantages. From within, we’re able to carry out close-up surveys of the Milky Way’s stellar population and its chemical compositions. That gives researchers the tools they need to compare our own galaxy to the many millions of others in the Universe.

This week, an international team of researchers from the USA, UK, and Chile released a paper that does just that. They dug through a catalogue of ten thousand galaxies produced by the Sloan Digital Sky Survey, searching for galaxies with similar attributes to our own.

They discovered that the Milky Way has twins – many of them – but just as many that are only superficially similar, with fundamental differences buried in the data. What they discovered has implications for the future evolution of our own galaxy.