Astronomy Archives

January 11, 2021January 11, 2021 by Ralph Crewe

The Mystery of Sunquakes is Deep; One Million Meters Deep!

Lead Image: Side-by-side of M-Class solar flare in visible and ultraviolet light. The ‘IP’ in the timeline indicates ‘impulsive flare’, and the following ripples can be seen radiating in the ultraviolet for up to 42 minutes following. Credit: NASA/SDO

The Sun, as it turns out, is a pretty big deal. The thermonuclear behemoth at the center of the solar system makes up well over 99% of all the mass in the solar system. Despite being the most well-studied star in the universe, there are still many mysteries about its works.

One of the Sun’s mysteries is the nature of sunquakes, massive ripples traveling thousands of kilometers across the sun’s surface. Occasionally, when a solar flare erupts, so-called seismic transients can be seen rippling through the solar surface over the next hour. The energy source driving these ripples was thought to be either the transient heating of the solar atmosphere during the flare event or by the powerful flexing of magnetic flux applied directly to the photosphere(the sun’s visible surface) itself, also originating in the flare event above. Using data from the Solar Dynamics Observatory (SDO), scientists have published a paper in the Astrophysical Journal of Letters that, for the first time, describes submerged sources of transient acoustic emission (sunquakes). The source of these mysterious waves seems to be, as it turns out, a thousand kilometers deep below, in the churning, seething hot interior of the star.

January 6, 2021January 5, 2021 by Paul M. Sutter

There Should be a few Supernovae in the Milky Way Every Century, but we’ve Only Seen 5 in the Last 1000 Years. Why?

This image of the supernova remnant SN 1987A was taken by the NASA/ESA Hubble Space Telescope in January 2017 using its Wide Field Camera 3 (WFC3). Since its launch in 1990 Hubble has observed the expanding dust cloud of SN 1987A several times has helped astronomers get a better understanding of these cosmic explosions. Supernova 1987A is located in the centre of the image amidst a backdrop of stars. The bright ring around the central region of the exploded star is material ejected by the star about 20 000 years before the actual explosion took place. The supernova is surrounded by gaseous clouds. The clouds’ red colour represents the glow of hydrogen gas. Image Credit: NASA, ESA, and R. Kirshner (Harvard-Smithsonian Center for Astrophysics and Gordon and Betty Moore Foundation) and P. Challis (Harvard-Smithsonian Center for Astrophysics)

Our galaxy hosts supernovae explosions a few times every century, and yet it’s been hundreds of years since the last observable one. New research explains why: it’s a combination of dust, distance, and dumb luck.

January 6, 2021January 6, 2021 by David Dickinson

Japan to Launch ‘Wooden Satellite’ in 2023

What a proposed wooden satellite could (and could not) accomplish.

A strange satellite proposal made at the end of 2020 by a Japanese company had many space pundits scratching their heads into 2021.

The proposal came out of Kyoto University in partnership with Sumitomo Forestry in Japan, though most of the information on the project comes from a BBC post quoting Japanese Aerospace Exploration Agency (JAXA) astronaut and Kyoto University professor Takao Doi, who flew aboard the U.S. space shuttle on missions STS-87 and STS-123 to the International Space Station. STS-123 delivered and installed JAXA’s Kib? module in 2008.

January 5, 2021January 5, 2021 by Evan Gough

Here’s the Asteroid Hayabusa2 is Going to be Visiting Next

The asteroid 1998 KY26 (the point of light located at where the two lines would cross) captured by Hyper Suprime-Cam mounted on the Subaru Telescope. The blurring of the background stars is due to the motion of the telescope tracking the asteroid. Five shots, each with a 2-minute exposure time, taken during 2:04–2:16 on December 10, 2020 (Hawai?i Standard Time) were stacked to create this image. The field of view is 30 x 15 arcseconds. (Credit: NAOJ)

Check out this image of asteroid 1998 KY₂₆ from the Subaru Telescope. It’s not exactly beautiful, but it’s not intended to be. The compelling thing about this image isn’t its attractiveness, it’s the context. This small asteroid is the next target for Japan’s Hayabusa2 spacecraft.

January 5, 2021January 5, 2021 by Paul M. Sutter

Missing: Supermassive Black Hole With up to 100 BILLION Times the Mass of the Sun

The massive galaxy cluster Abell 2261 should have a supermassive black hole in its center. But it doesn’t. Astronomers have looked everywhere – even between the couch cushions. What’s going on?

January 5, 2021January 5, 2021 by Matt Williams

Astronomers set a new Record and Find the Farthest Galaxy. Its Light Took 13.4 Billion Years to Reach us

Galaxy GN-z11 superimposed on an image from the GOODS-North survey. Credit: NASA/ESA/P. Oesch (Yale University)/G. Brammer (STScI)/P. van Dokkum (Yale University)/G. Illingworth (University of California, Santa Cruz)

Since time immemorial, philosophers and scholars have contemplated the beginning of time and even tried to determine when all things began. It’s only been in the age of modern astronomy that we’ve come close to answering that question with a fair degree of certainty. According to the most widely-accepted cosmological models, the Universe began with the Bang Bang roughly 13.8 billion years ago.

Even so, astronomers are still uncertain about what the early Universe looked like since this period coincided with the cosmic “Dark Ages.” Therefore, astronomers keep pushing the limits of their instruments to see when the earliest galaxies formed. Thanks to new research by an international team of astronomers, the oldest and most distant galaxy observed in our Universe to date (GN-z11) has been identified!

January 4, 2021January 4, 2021 by Matt Williams

Astronomers Discover Hundreds of High-Velocity Stars, Many on Their Way Out of the Milky Way

Since discovering the first one in 2005, astronomers have found hundreds of stars that travel fast enough that they could escape the Milky Way as HVSs. Image Credit: NAOC/Kong Xiao

Within our galaxy, there are thousands of stars that orbit the center of the Milky Way at high velocities. On occasion, some of them pick up so much speed that they break free of our galaxy and become intergalactic objects. Because of the extreme dynamical and astrophysical processes involved, astronomers are most interested in studying these stars – especially those that are able to achieve escape velocity and leave our galaxy.

However, an international team of astronomers led from the National Astronomical Observatories of China (NAOC) recently announced the discovery of 591 high-velocity stars. Based on data provided by the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) and the ESA’s Gaia Observatory, they indicated that 43 of these stars are fast enough to escape the Milky Way someday.

January 1, 2021January 1, 2021 by Matthew Cimone

Some of Hayabusa2’s Samples are as Big as a Centimeter

Soil Samples returned by the Hayabusa2 Spacecraft c. JAXA

A fireball hurtled across the sky on December 5^th – the sample return capsule from the Hayabusa2 asteroid mission by JAXA (Japan Aerospace Exploration Agency). The capsule landed in Woomera, a remote location in the Australian Outback. Earlier this month, the capsule’s sample containers revealed fine grain topsoil from asteroid 162173 Ryugu. A second sample container has since been opened that contains chunks up to an entire centimeter in size.

Soil Samples returned by the Hyabusa2 Spacecraft -c JAXA

December 30, 2020December 30, 2020 by Andy Tomaswick

Astronomers Capture a Direct Image of a Brown Dwarf

First direct image of a brown dwarf star in a system not unlike our own.

The field of exoplanet photography is just getting underway, with astronomers around the world striving to capture clear images of the more than 4000 exoplanets discovered to date. Some of these exoplanets are more interesting to image and research than others. That is certainly the case for a type of exoplanet called a brown dwarf. And now scientists have captured the first ever image of exactly that type of exoplanet.

December 28, 2020December 28, 2020 by Paul M. Sutter

Brines Could be Present on the Surface of Mars for up to 12 Hours, Never for a Full day

This illustration shows Jezero Crater — the landing site of the Mars 2020 Perseverance rover — as it may have looked billions of years go on Mars, when it was a lake. An inlet and outlet are also visible on either side of the lake. Image Credit: NASA/JPL-Caltech

We are extremely interested in the possibility of water on Mars, because where there’s water, there’s the potential for life. But a new study throws a bit of a wet blanket (pun intended) on that tantalizing possibility. Unfortunately, it looks like even the saltiest of brines can only exist on the Martian surface for up to a few hours at a time.