milky way Archives

November 20, 2023November 20, 2023 by Nancy Atkinson

Gaze Into the Heart of the Milky Way in This Latest JWST Image

James Webb Space Telescope’s NIRCam (Near-Infrared Camera) instrument reveals a 50 light-years-wide portion of the Milky Way’s dense center. An estimated 500,000 stars shine in this image of the Sagittarius C (Sgr C) region, along with some as-yet unidentified features. Credit: NASA, ESA, CSA, STScI, S. Crowe (UVA).

Thanks to its infrared capabilities, the James Webb Space Telescope (JWST) allows astronomers to peer through the gas and dust clogging the Milky Way’s center, revealing never-before-seen features. One of the biggest mysteries is the star forming region called Sagittarius C, located about 300 light-years from the Milky Way’s supermassive black hole. An estimated 500,000 stars are forming in this region that’s being blasted by radiation from the densely packed stars. How can they form in such an intense environment?

Right now, astronomers can’t explain it.

November 9, 2023November 9, 2023 by Evan Gough

Astronomers Find Dozens of Massive Stars Fleeing the Milky Way

This is Zeta Ophiuchi, a runaway star observed by Spitzer. The star is creating a bow shock as it travels through an interstellar dust cloud. A new study found dozens of new runaway stars in the Milky Way. Image Credit: NASA/JPL-Caltech

The Milky Way can’t hold onto all of its stars. Some of them get ejected into intergalactic space and spend their lives on an uncertain journey. A team of astronomers took a closer look at the most massive of these runaway stars to see what they could find out how they get ejected.

October 13, 2023October 13, 2023 by Evan Gough

A Huge New Gaia Data Release: More Stars, Gravitational Lenses and Asteroids

The ESA's Gaia observatory expanded its targets to include the tightly-packed center of Omega Centauri, an ancient globular cluster. Image Credit: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO. Acknowedgements: Michele Trabucchi, Nami Mowlavi and Thomas Lebzelter

The ESA’s Gaia mission is releasing a new tranche of astronomical data. The mission has released three regular, massive hauls of data since it launched in 2013, named Gaia DR1, DR2, and DR3. The ESA is calling this one a ‘focused product release,’ and while it’s smaller than the previous three releases, it’s still impactful.

September 11, 2023September 22, 2023 by Evan Gough

JWST Accidentally Found 21 Brown Dwarfs

This artist's conception illustrates the brown dwarf named 2MASSJ22282889-431026, observed by NASA's Hubble and Spitzer space telescopes. Brown dwarfs are more massive and hotter than planets but lack the mass required to become stars. Image credit: NASA

When you launch humanity’s most powerful telescope, you expect results. The JWST has delivered excellent results by detecting ancient galaxies, identifying chemicals in exoplanet atmospheres, and peering into star-forming regions with more detail and clarity than any other telescope.

But every time a new telescope is about to enter service, astronomers tell us they’re excited not only about the expected results but also about the surprising results. And like other telescopes, the JWST has also delivered some surprises. While going about its business, the JWST has discovered 21 brown dwarfs.

September 6, 2023September 6, 2023 by Evan Gough

JWST Gazes into the Dark Molecular Clouds at the Heart of the Milky Way

The Central Molecular Zone; the Heart of the Milky Way. Image Credit: Henshaw / MPIA

There’s an unusual object near the Milky Way’s heart that astronomers call “The Brick.” It’s a massive cloud of gas called an infrared dark cloud (IDC). The Brick is dense and turbulent like others of its type, but for some reason, it shows few signs of star formation.

Why?

June 12, 2023June 12, 2023 by Scott Alan Johnston

These are the Fastest Stars in the Galaxy

Artist concept showing a hypervelocity star escaping our galaxy. Credit: NASA, ESA, and G. Bacon (STScI)

Until recently, there were only ten known stars on trajectories that will allow them to escape the Milky Way Galaxy, thrown astray by powerful supernova explosions. A new study using data from ESA’s Gaia survey this June has revealed an additional six runaways, two of which break the record for the fastest radial velocity of any runaway star ever seen: 1694 km/s and 2285 km/s.

June 1, 2023June 1, 2023 by Brian Koberlein

Exactly How Massive is the Milky Way?

Artist depiction of the Milky Way galaxy. Credit: Andrew Z. Colvin

How do you weigh a galaxy? It’s an astronomical challenge, particularly if it’s the galaxy you call home. It turns out there are several ways to get a handle on the mass of the Milky Way, and a recent study summarizes these methods to present the best value.

April 23, 2023April 23, 2023 by Scott Alan Johnston

The Milky Way has Trapped the Large Magellanic Cloud With its Gravity. What Comes Next?

Our galaxy’s largest nearby companion is the Large Magellanic Cloud (LMC), a dwarf galaxy visible to the naked eye in the Southern Hemisphere. In recent years, new theoretical research and better observational capabilities have taught astronomers a great deal about our (not-so-little) neighbour. It’s becoming increasingly clear that the LMC is helping shape the Milky Way’s evolution.

January 18, 2023January 18, 2023 by Nancy Atkinson

You’re Looking at a Map of the Milky Way’s Magnetic Field

Colour shows the polarized microwave emission measured by QUIJOTE. The pattern of lines superposed shows the direction of the magnetic field lines. Credit: The QUIJOTE Collaboration.

Using telescopes that study the sky in the microwave part of the electromagnetic spectrum, astronomers have successfully mapped the structure of the magnetic field of the Milky Way galaxy. While magnetic fields are difficult to measure in space, an international team of astronomers used the Teide Observatory on Tenerife in the Canary Islands to conduct 10 years of observations.

January 13, 2023January 13, 2023 by Matt Williams

Astronomers Used a Fast Radio Burst to Probe the Structure of the Milky Way

Artist's impression of the huge halo of hot gas surrounding the Milky Way Galaxy. Credit: NASA

In the past decade and a half, hundreds of Fast Radio Bursts (FRBs) have been detected by astronomers. These transient energetic bursts occur suddenly, typically last for just a few milliseconds, and are rarely seen again (except in the rare case of repeating bursts). While astronomers are still not entirely sure what causes this phenomenon, FRBs have become a tool for astronomers hoping to map out the cosmos. Based on the way radio emissions are dispersed as they travel through space, astronomers can measure the structure and distribution of matter in and around galaxies.

Using the Deep Synoptic Array (DSA) at the Owens Valley Radio Observatory (OVRO), a team of astronomers from Caltech and Cornell University used an intense FRB from a nearby galaxy to probe the halo of hot gas that surrounds the Milky Way. Their results show that our galaxy has significantly less visible (“baryonic” or “normal”) matter than previously expected. These findings support theories that matter is regularly ejected from our galaxy due to stellar winds, supernovae, and accreting supermassive black holes (SMBHs).