Astronomy Archives

March 27, 2020March 28, 2020 by Paul M. Sutter

The heliosphere looks a lot weirder than we originally thought

A model of the heliosphere as imagined by new research. Yes, it looks like an ugly croissant. Image courtesy of Merav Opher, et. al

Every second of every day, our sun spits out a stream of tiny high-energy particles, known as the solar wind. This wind blows throughout the solar system, extending far beyond the orbits of the planets and out into interstellar space.

But the farther from the sun the wind gets, the more slowly it streams, changing from the raging torrent that the inner planets experience (strong enough to cause the aurora) into nothing more than an annoying drizzle. And far enough away – about twice the orbit of Neptune – it meets and mingles with all the random bits of energetic junk just floating around amongst the stars.

March 26, 2020March 26, 2020 by Nancy Atkinson

Highest Resolution Mosaic Image of the Surface of Bennu

This global map of asteroid Bennu’s surface is a mosaic of images collected by NASA’s OSIRIS-REx spacecraft between Mar. 7 and Apr. 19, 2019. Credit: NASA/Goddard/University of Arizona

NASA and the University of Arizona have released a stunning new global map of asteroid Bennu. At 2 inches (5 cm) per pixel, this is the highest-resolution global map of any planetary body. This hi-res map will help guide the OSIRIS-REx spacecraft to the surface of the asteroid to collect a sample, currently scheduled for late August 2020.

March 25, 2020 by Matt Williams

Even More Repeating Fast Radio Bursts Discovered

Artist’s impression of CSIRO’s Australian SKA Pathfinder (ASKAP) radio telescope finding a fast radio burst and determining its precise location. The KECK, VLT and Gemini South optical telescopes joined ASKAP with follow-up observations to image the host galaxy. Credit: CSIRO/Dr Andrew Howells

In September of 2017, the Canadian Hydrogen Intensity Mapping Experiment (CHIME) in British Columbia commenced operations, looking for signs of Fast Radio Bursts (FRBs) in our Universe. These rare, brief, and energetic flashes from beyond our galaxy have been a mystery ever since the first was observed a little over a decade ago. Of particular interest are the ones that have been found to repeat, which are even rarer.

Before CHIME began collecting light from the cosmos, astronomers knew of only thirty FRBs. But thanks to CHIME’s sophisticated array of antennas and parabolic mirrors (which are especially sensitive to FRBs) that number has grown to close to 700 (which includes 20 repeaters). According to a new study led by CHIME researchers, this robust number of detections allows for new insights into what causes them.

March 25, 2020May 19, 2020 by David Dickinson

Following Comet Y1 ATLAS: the ‘Lost Comet’ of Spring

Got clear skies? If you’re like us, you’ve been putting the recent pandemic-induced exile to productive use, and got out under the nighttime sky. And though 2020 has yet to offer up a good bright ‘Comet of the Century’ to keep us entertained, there have been a steady stream of good binocular comets for northern hemisphere viewers, including C/2017 T2 PanSTARRS and C/2019 Y4 ATLAS. This week, I’d like to turn your attention to another good binocular comet that is currently at its peak: the ‘other’ comet ATLAS, C/2019 Y1 ATLAS.

March 24, 2020March 24, 2020 by Matt Williams

Apollo 15 Astronaut Al Worden has Passed Away

Apollo Astronaut Alfred Worden (1932-2020). Credit: NASA

Last Wednesday (March 18th), the world was saddened to hear of the death of Apollo astronaut Alfred “Al” Worden, who passed away after suffering a stroke at an assisted living facility in Texas. A former Colonel in the US Marine Corps who obtained his Bachelor of Science from West Point Academy in 1955 and his Master of Science at the University of Michigan in 1963, Worden went on to join NASA.

March 24, 2020March 24, 2020 by Matt Williams

How Researchers Produce Sharp Images of a Black Hole

In April of 2019, the Event Horizon Telescope collaboration history made history when it released the first image of a black hole ever taken. This accomplishment was decades in the making and triggered an international media circus. The picture was the result of a technique known as interferometry, where observatories across the world combined light from their telescopes to create a composite image.

This image showed what astrophysicists have predicted for a long time, that extreme gravitational bending causes photons to fall in around the event horizon, contributing to the bright rings that surround them. Last week, on March 18th, a team of researchers from the Harvard-Smithsonian Center for Astrophysics (CfA) announced new research that shows how black hole images could reveal an intricate substructure within them.

March 23, 2020 by Matt Williams

Another Incredible Picture of Mars, This Time From a Region Just Outside Valles Marineris

HiRISE image showing the terrain in Juventae Chasma. Credit: NASA/JPL/UArizona

The Mars Reconnaissance Orbiter (MRO) delivers once again! Using its advanced imaging instrument, the High Resolution Imaging Experiment (HiRISE) camera, the orbiter captured a breathtaking image (shown below) of the plains north of Juventae Chasma. This region constitutes the southwestern part of Valles Marineris, the gigantic canyon system that runs along the Martian equator.

March 19, 2020 by Matt Williams

Blazar Found Blazing When the Universe was Only a Billion Years Old

Artist's impression of a quasar and a relativistic jet emanating from the center. Credit: NASA

Since the 1950s, astronomers have known of galaxies that have particularly bright centers – aka. Active Galactic Nuclei (AGNs) or quasars. This luminosity is the result of supermassive black holes (SMBHs) at their centers consuming matter and releasing electromagnetic energy. Further studies revealed that there are some quasars that appear particularly bright because their relativistic jets are directed towards Earth.

In 1978, astronomer Edward Speigel coined the term “blazar” to describe this particular class of object. Using the telescopes at the Large Binocular Telescope Observatory (LBTO) in Arizona, a research team recently observed a blazar located 13 billion light-years from Earth. This object, designated PSO J030947.49+271757.31 (or PSO J0309+27), is the most distant blazar ever observed and foretells the existence of many more!

March 17, 2020 by David Dickinson

Dawn Patrol: Following this Month’s ‘March of the Planets’

Slim Moon — A slender waning crescent Moon as seen from Jimena de la Frontera, Spain. Credit: Dave Dickinson

Are you hanging out at home this week, and looking to observe some naked eye planets? As we mentioned last week, while Venus is shining bright in the dusk sky, all of the other four naked eye planets of Mars, Saturn, Jupiter and Mercury are skulking in the early dawn.

March 13, 2020March 26, 2020 by Matt Williams

A Star Has Been Found That Pulsates, But Only on One Side

An artist’s impression of the star with its tidally locked red dwarf companion. Credit: Gabriel Pérez Díaz (IAC)

In the 17th century, astronomers witnessed many stellar events that proved that the starry sky was not “fixed and eternal.” This included stars whose brightness varied over time – aka. “variable stars.” By the 20th century, many variable stars had been cataloged and astronomers have discerned subclasses of them as well – notably, stars that swell and shrink, known as pulsating variables.

In all cases, these variable stars were found to have rhythmic pulsations that were visible from all sides. But a recent discovery by an international team has confirmed that there are variable stars that can pulse from only one side. This pulsating star, part of a system known as HD 74423, is located about 1,500 light-years from Earth and is the first of its kind to be found.