Universe Today

April 27, 2021April 27, 2021 by Brian Koberlein

Smallest, Closest Black Hole Ever Discovered is Only 1,500 Light-Years Away

Artist concept of V723 Mon and its companion. Lauren Fanfer/Ohio State

In theory, a black hole is easy to make. Simply take a lump of matter, squeeze it into a sphere with a radius smaller than the Schwarzschild radius, and poof! You have a black hole. In practice, things aren’t so easy. When you squeeze matter, it pushes back, so it takes a star’s worth of weight to squeeze hard enough. Because of this, it’s generally thought that even the smallest black holes must be at least 5 solar masses in size. But a recent study shows the lower bound might be even smaller.

April 25, 2021April 25, 2021 by Brian Koberlein

A new Technique Could use Quasars to Directly Measure the Expansion Rate of the Universe

an artistic concept of a quasar — Concept image of a galactic quasar. Astronomers used the Event Horizon Telescope to study details at the heart of one like this called NRAO 530. Credit: ParallelVision, Pixabay

One of the biggest challenges to measuring the expansion of the universe is the fact that many of the methods we use are model-dependent. The most famous example is the use of distant supernovae, where we compare the standard brightness of a Type Ia supernova with their apparent brightness to find their distance. But knowing the standard brightness depends upon comparing them to the brightness of Cepheid variables which is in turn determined by measuring the distances of nearby stars via parallax. Every step of this cosmic distance ladder depends upon the step before it.

April 24, 2021April 24, 2021 by Matt Williams

Animation Shows how Saturn’s Rings Move at Different Speeds

Saturn's F ring is extremely narrow compared to the historic A, B and C rings. It measure just a few hundred kilometers across. Credit: NASA/Cassini

Saturn’s rings are one of the most recognized and revered celestial objects known to the human race. From a distance, they look like a disk of layered crystal or multicolored disks within disks that wrap around Saturn’s hazy umber face. When viewed up close, we see that these rings are actually particles of water ice (from microns to icebergs), as well as silicates, carbon dioxide, and ammonia.

We would also noticed that the rings have some interesting orbital mechanics. In fact, each ring has a different orbit that is the result of its proximity to Saturn (i.e., the closer they are, the faster they orbit). To illustrate what this complex system look like, NASA Fellow Dr. James O’Donoghue created a stunning animation that shows how each of Saturn’s major ring segments (A-Ring to F-Ring) orbit together around the planet.

April 23, 2021April 23, 2021 by Matt Williams

A Recent Megaflare Shows that Proxima Centauri is not a Nice Place to Live

An artist's conception of a violent flare erupting from the red dwarf star Proxima Centauri. Such flares can obliterate atmospheres of nearby planets. Credit: NRAO/S. Dagnello.

Proxima b, the closest exoplanet to our Solar System, has been a focal point of scientific study since it was first confirmed (in 2016). This terrestrial planet (aka. rocky) orbits Proxima Centauri, an M-type (red dwarf) star located 4.2 light-years beyond our Solar System – and is a part of the Alpha Centauri system. In addition to its proximity and rocky composition, it is also located within its parent star’s habitable zone (HZ).

Until a mission can be sent to this planet (such as Breakthrough Starshot), astrobiologists are forced to postulate about the possibility that life could exist there. Unfortunately, an international campaign that monitored Proxima Centauri for months using nine space- and ground-based telescopes recently spotted an extreme flare coming from the star, one which would have rendered Proxima b uninhabitable.

April 23, 2021April 23, 2021 by Scott Alan Johnston

Perseverance Successfully Extracts Oxygen From the Martian Atmosphere. About 10 Minutes of Breathing Time for an Astronaut

Humanity achieved an incredible series of new milestones on Mars this week. It began on Monday April 19th, when the Ingenuity helicopter demonstrated the first-ever powered, controlled flight on another world. And now, for the first time, the Perseverance rover has used ingredients from the Martian atmosphere to create breathable oxygen, in a test that might pave the way for future astronauts to ‘live off the land’ on the Red Planet.

April 22, 2021April 22, 2021 by Andy Tomaswick

Giant Planet is Found at an Extreme Distance From its Star

One of the best things about the sheer number of exoplanets that astronomers are currently finding is how some are just very different. Those differences can sometimes undermine standing theories, and prompt scientists to start considering new theories that account for the new information. That is undoubtedly what will happen to accommodate a new massive planet found by a team led by Dutch scientists. This planet is unique in one very special way – it is about 110 times farther away from its star than the Earth is from the sun.

April 21, 2021April 21, 2021 by Matt Williams

Blue Origin’s Latest New Shepard Flight is a Success, With Passengers Climbing on Board (and Getting off Again Before it Flew)

In 2000, Amazon founder and CEO Jeff Bezos founded Blue Origin, a commercial space company intended to become one of the crown jewels of his financial empire. Unfortunately, Blue Origin has lost ground in recent years to companies like SpaceX, which have been pushing the envelope with the development of reusable launch systems, resupply services, and human-rated spacecraft.

To address this, Bezos recently stepped down as CEO of Amazon to devote more attention to Blue Origin and other projects. On Wednesday, April 14^th, the company hit a milestone when their New Shepard spacecraft (named in honor of famed astronaut Alan Shepard) conducted its fifteenth consecutive mission (NS-15) to space and back. This “crew rehearsal” mission brings Blue Origin one step closer to launching crews and tourists into space.

April 21, 2021April 21, 2021 by Nancy Atkinson

New Horizons is Now 50 Astronomical Units Away From the Sun

Currently exploring the Kuiper Belt, New Horizons is just one of five spacecraft to reach beyond 50 astronomical units, on its way out of the solar system and, eventually, into interstellar space. (Credit: NASA/Johns Hopkins APL/Southwest Research Institute)

As the New Horizons spacecraft hurtles out towards interstellar space, it has now reached an historical milestone. On April 17, 2021, New Horizons passed 50 astronomical units, or 50 times Earth’s distance from the Sun. It is just the 5^th spacecraft to reach that distance, joining the Voyagers 1 and 2 and the Pioneers 10 and 11.

April 21, 2021April 21, 2021 by David Dickinson

Catch Comet R4 ATLAS as it Nears Earth

The coming weeks are a great time to catch comet C/2020 R4 ATLAS… while you can.

Looking to do some springtime astronomy? With temperatures warming up in the northern hemisphere in April through May, galaxy season is upon us. At dusk, the area in the Bowl of Virgo asterism rising in the east is rife with clusters of galaxies that spill over into the adjacent constellations of Coma Berenices and Boötes…

But this May, keep an eye out for a fuzzball interloper that is not a galaxy: Comet C/2020 R4 ATLAS.

April 20, 2021April 20, 2021 by Matt Williams

What if Starship Didn’t Do a Landing Burn at All?

Thanks to Musk’s preference for sharing his ideas directly with the public, SpaceX is inundated with all kinds of proposals from citizen scientists and space-exploration enthusiasts – some of which are practical and some outlandish. This latest proposal definitely straddles these two categories! In an animation shared via Twitter, 3D digital artist Nick Henning offered an alternative vision for a SpaceX tower that could “catch” the Super Heavy.