The Earliest Galaxies Rotated Slowly, Revving up Over Billions of Years

This image features the spiral galaxy NGC 691, imaged in fantastic detail by Hubble’s Wide Field Camera 3 (WFC3). This galaxy is the eponymous member of the NGC 691 galaxy group, a group of gravitationally bound galaxies that lie about 120 million light-years from Earth.  Objects such as NGC 691 are observed by Hubble using a range of filters. Each filter only allows certain wavelengths of light to reach Hubble’s WFC3. The images collected using different filters are then coloured by specialised visual artists who can make informed choices about which colour best corresponds to which filter. By combining the coloured images from individual filters, a full-colour image of the astronomical object can be recreated. In this way, we can get remarkably good insight into the nature and appearance of these objects. Links Video of the Eponymous NGC 691

A team of astronomers have used the ALMA telescope to find a slowly-rotating galaxy in the early universe. That galaxy is the youngest ever found with a measured rotation, and it’s much slower than present-day galaxies.

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Do Supermassive Black Holes Prematurely end Star Formation in Some Galaxies?

Sagittarius A
Image of Sagittarius A, the complex radio source at the center of the Milky Way.

Some galaxies, like the Milky Way, have maintained regular star formation for billions of years. Others, like large elliptical galaxies, are “red and dead.” Star formation in those galaxies shut off long ago. Astronomers have long suspected the nefarious influence of supermassive black holes, and new research has found the smoking gun.

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The Stars in Other Galaxies are Generally Heavier Than the Milky Way’s Stars

The Fornax Galaxy Cluster is one of the closest of such groupings beyond our Local Group of galaxies. This new VLT Survey Telescope image shows the central part of the cluster in great detail. At the lower-right is the elegant barred-spiral galaxy NGC 1365 and to the left the big elliptical NGC 1399.

How many of what kinds of stars live in other galaxies? It seems like a simple question, but it’s notoriously hard to pin down, because astronomers have such a difficult time estimating stellar populations in remote galaxies. Now a team of astronomers has completed a census of over 140,000 galaxies and found that distant galaxies tend to have heavier stars.

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Dark Stars: The First Stars in the Universe Could Have Been Powered by Annihilating Dark Matter

A recent survey has discovered the first stars of the Milky Way. Credit: Gabriel Pérez, SMM (IAC)

Dark matter doesn’t really do much of anything in the present-day universe. But in the early days of the cosmos there may have been pockets of dark matter with high enough density that they provided a source of heat for newly forming stars. Welcome to the strange and wonderful world of “dark stars.”

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Could we Detect Dark Matter’s Annihilation Within Globular Clusters?

Globular Cluster
A Hubble Space Telescope image of the typical globular cluster Messier 80, an object made up of hundreds of thousands of stars and located in the direction of the constellation of Scorpius. The Milky Way galaxy has an estimated 160 globular clusters of which one quarter are thought to be ‘alien’. Image: NASA / The Hubble Heritage Team / STScI / AURA. Click for hi-resolution version.

A team of astronomers studied two nearby globular clusters, 47 Tucanae and Omega Centauri, searching for signals produced by annihilating dark matter. Those the searches turned up empty, they weren’t a failure. The lack of a detection placed strict upper limits on the mass of the hypothetical dark matter particle.

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We can Probably Find Supernovae Enhanced by Gravitational Lensing, We Just Need to Look

Using the microlensing metthod, a team of astrophysicists have found the first extra-galactic planets! Credit: NASA/Tim Pyle

Gravitational lensing provides an opportunity to see supernovae and other transients much farther than we normally can. A new research proposal outlines a plan to use a comprehensive catalog of strong gravitational lenses to capture these rare events at extreme distances.

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What Does Micrometeoroid Damage do to Gossamer Structures Like Webb’s Sunshield?

Sunshield test unit on NASA's James Webb Space Telescope is unfurled for the first time at Northrup Grumman. Credit: NASA

Tiny little bullets flood the solar system, each micrometeoroid a potential hazard. New research has found that the James Webb Space Telescope’s thin sunshields, and future inflatable spacecraft, may be at risk.

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Scientists Create Molecules that can Follow Darwinian Evolution

photo of a turtle swimming underwater
Photo by Belle Co on Pexels.com

A team of researchers at the University of Tokyo have discovered a set of RNA molecules that are capable of replication and diversification. This potentially allows the molecules to undergo Darwinian evolution, pointing the way to a possible first step to life on Earth. As lead author Assistant Professor Ryo Mizuuchi said, “The results could be a clue to solving the ultimate question that human beings have been asking for thousands of years — what are the origins of life?”

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