Universe Today

December 12, 2023December 13, 2023 by Matt Williams

We've Entered a New Era: The Lunar Anthropocene

Humans on the Moon. Image credit: Envato Elements

For almost half a century, the term “Anthropocene” has been informally used to describe the current geological epoch. The term acknowledges how human agency has become the most significant factor when it comes to changes in Earth’s geology, landscape, ecosystems, and climate. According to a new study by a team of geologists and anthropologists, this same term should be extended to the Moon in recognition of humanity’s exploration (starting in the mid-20th century) and the growing impact our activities will have on the Moon’s geology and the landscape in the near future.

December 12, 2023December 12, 2023 by Andy Tomaswick

The Positions of Stars on an Ancient Navigation Device Tell us When it was Made

Astrolabes serve two purposes. First, they are useful as an astronomical tool, especially for finding a ship’s latitude. But second, they are works of art in themselves. Besides having to be precise, many are beautiful. They are even seeing a resurgence in popularity as collectors lap up even those made by modern manufacturing processes because of their aesthetic appeal. Now, a new paper adds to their uses – a self-referential ability to mark what year they were made by the patterns of the stars they reference.

December 12, 2023December 13, 2023 by Nancy Atkinson

Review: Unistellar’s eQuinox 2 Telescope and New Smart Solar Filter

The Sun on November 27, 2023, observed using the Unistellar eQuinox 2 and the new smart solar filter. Credit: Nancy Atkinson and Unistellar.

I recently had the chance to try out one of Unistellar’s smart telescopes, the eQuinox 2. Unparalleled in its ease of use, I was literally viewing distant nebula, galaxies, and star clusters within 15 minutes of opening the box.

I also had the opportunity to try out Unistellar’s new Smart Solar Filter, which I’ll discuss more below. But first, more about the telescope itself:

December 12, 2023December 12, 2023 by Carolyn Collins Petersen

Three Baby Stars Found at the Heart of the Milky Way

The image, taken with ESO's Very Large Telescope in Chile, shows a high-resolution view of the innermost parts of the Milky Way. In the new study, the researchers examined the dense nuclear star cluster shown in detail here. Credit: ESO. Milky Way in the background. Image credit: NASA

The core of our Milky Way is buzzing with stars. Recently astronomers reported that it contains at least one ancient star that formed outside our galaxy. Now, an international research team reports finding a grouping of very young ones there, as well. Their presence upends ideas about star birth in that densely packed region of space.

December 11, 2023December 11, 2023 by Evan Gough

Exomoons Defy Discovery

So far we only know of two exoplanets with candidate exomoons. But even those two may be false positives. Image Credit: NASA

For a long time, we wondered if other stars hosted planets like the Sun does. Finally, in the 1990s, we got our answer. Now, another question lingers.

Most of the planets in our Solar System have moons. Do exoplanets have exomoons?

December 11, 2023December 14, 2023 by Matt Williams

Why Was it Tricky to Know the Distances to Galaxies JWST Was Seeing?

Obtaining accurate redshift measurements is a challenge, even with telescopes like Webb. Credit: NASA

One of the chief objectives of the James Webb Space Telescope (JWST) is to study the formation and evolution of the earliest galaxies in the Universe, which emerged more than 13 billion years ago. To this end, scientists must identify galaxies from different cosmological epochs to explore how their properties have changed over time. This, in turn, requires precise dating techniques so astronomers are able to determine when (in the history of the Universe) an observed galaxy existed. The key is to measure the object’s redshift, which indicates how long its light has been traveling through space.

This is the purpose of the Cosmic Evolution Early Release Science Survey (CEERS), a collaborative research group that analyzes Webb data to learn more about galactic evolution. These galaxies are known as “high-redshift,” meaning that their light emissions are redshifted all the way into the infrared spectrum. Galaxies that existed ca. 13 billion years ago can only be observed in the near-infrared spectrum, which is now possible thanks to Webb’s Near-Infrared Camera (NIRCam). Even so, obtaining accurate redshift measurements from such distant galaxies is a very tricky, and requires advanced techniques.

December 11, 2023December 11, 2023 by Evan Gough

Psyche Gives Us Its First Images of Space

NASA's Psyche spacecraft has released its first images. The spacecraft is firing on all cylinders as it makes its way toward its target, the metal-rich asteroid with the same name. Image Credit: NASA

NASA’s Psyche mission began eight weeks ago when it launched from the Kennedy Space Center. While it won’t reach its objective, the metal-rich asteroid Psyche, until 2029, the spacecraft has already travelled 26 million km (16 million miles.) During that time, it’s already had its share of success as it ticks off items on its checklist of tests.

Now, we have our first images from Psyche. And while they don’t show us anything about its eventual target, they give us a behind-the-scenes look at how complex spacecraft prepare themselves as they cruise toward their destinations.

December 11, 2023December 11, 2023 by Evan Gough

What Would a Modern “Golden Record” Include?

Voyager's Golden Record. Credit: NASA/JPL

Now that several decades have passed since the launch of Voyager 1 and Voyager 2 in 1977, we look back on that time with a hazy sense of history and what the event meant for humanity’s ongoing odyssey. While the Voyager spacecraft were sober scientific missions, they also carried with them a hint of the deeper yearnings that lie inside humanity’s heart: the Golden Records.

December 11, 2023December 11, 2023 by Nancy Atkinson

Amateur Astronomers Found Planets Crashing Into Each Other

Artist impression of two colliding planets.

Astronomy is one of the sciences where amateurs make regular contributions. Over the years, members of the public have made exciting discoveries and meaningful contributions to the scientific process, either through direct observing, citizen science projects, or through combing through open data from the various space missions.

Recently, amateur astronomer Arttu Sainio saw a conversation on X (Twitter) where researchers were discussing the strange behavior of a dimming sun-like star. Intrigued, Arttu decided to look at the data on this star, called Asassn-21qj, on his own. Looking at archival data from NASA’s NEOWISE mission, Sainio was surprised to find that the star had dimmed before, with an unexpected brightening in infrared light two years before the optical dimming event. So, he joined the discussion on social media and shared his finding – which led to more amateurs joining the research, which lead to an incredible discovery.

December 11, 2023December 11, 2023 by David Dickinson

Why 2023 is a Fine Year for the Geminid Meteors

One of the best meteor showers of the year, the Geminids puts on a fine display in 2023.

December has one more sky watching treat in store for 2023. If skies are clear, watch for what’s rapidly becoming the best annual meteor shower of the year: the Geminid meteors.