Space News and Discussions

[weatheriscool]

Parker solar probe captures its first images of Venus' surface in visible light
https://phys.org/news/2022-02-parker-so ... mages.html
by Mara Johnson-Groh, NASA's Goddard Space Flight Center

NASA's Parker Solar Probe has taken its first visible light images of the surface of Venus from space.

Smothered in thick clouds, Venus' surface is usually shrouded from sight. But in two recent flybys of the planet, Parker used its Wide-Field Imager, or WISPR, to image the entire nightside in wavelengths of the visible spectrum—the type of light that the human eye can see—and extending into the near-infrared.

The images, combined into a video, reveal a faint glow from the surface that shows distinctive features like continental regions, plains, and plateaus. A luminescent halo of oxygen in the atmosphere can also be seen surrounding the planet.

"We're thrilled with the science insights Parker Solar Probe has provided thus far," said Nicola Fox, division director for the Heliophysics Division at NASA Headquarters. "Parker continues to outperform our expectations, and we are excited that these novel observations taken during our gravity assist maneuver can help advance Venus research in unexpected ways."

Such images of the planet, often called Earth's twin, can help scientists learn more about Venus' surface geology, what minerals might be present there, and the planet's evolution. Given the similarities between the planets, this information can help scientists on the quest to understand why Venus became inhospitable and Earth became an oasis.

"Venus is the third brightest thing in the sky, but until recently we have not had much information on what the surface looked like because our view of it is blocked by a thick atmosphere," said Brian Wood, lead author on the new study and physicist at the Naval Research Laboratory in Washington, DC. "Now, we finally are seeing the surface in visible wavelengths for the first time from space."

[wjfox]

Supercomputers Simulated a Black Hole And Found Something We've Never Seen Before

10 FEBRUARY 2022

While black holes might always be black, they do occasionally emit some intense bursts of light from just outside their event horizon. Previously, what exactly caused these flares had been a mystery to science.

That mystery was solved recently by a team of researchers that used a series of supercomputers to model the details of black holes' magnetic fields in far more detail than any previous effort. The simulations point to the breaking and remaking of super-strong magnetic fields as the source of the super-bright flares.

[...]

Simulations showed the breaking and making of magnetic field connections that were invisible at previously available resolutions. Ripperda and his colleagues' image had 1,000 times the resolution of any previously available black hole simulation.

The most accurate simulations in the world can't make up for an incorrect model, so previous simulations ignored basic features of black hole interactions.

With high resolution came greater understanding. The new simulations accurately modeled how the magnetic field process around the event horizon works.

https://www.sciencealert.com/black-hole ... they-do-it

[caltrek]

Distant Galaxies and the True Nature of Dark Matter
February 11, 2022

https://www.eurekalert.org/news-releases/943173

Introduction:

(Eureka Alert) At the centre of spiral galaxies – those near to us but also those billions of light-years away – there is a vast spherical region made up of dark matter particles. This region has two defining characteristics: a density that is constant out to a certain radius that amazingly expands over time, while the density decreases. This suggests the existence of a direct interaction between the elementary particles that make up the dark matter halo and those that make up ordinary matter – protons, electrons, neutrons, and photons. We anticipate that this hypothesis is in direct conflict with the current prevailing theory used to describe the universe – known as Lambda-Cold Dark Matter – which posits that particles of cold dark matter are inert and do not interact with any other particle except gravitationally.

These important findings have been reported in a new study, recently published in the prestigious Astronomy and Astrophysics journal, that studied a large number of distant galaxies, some seven billion light-years away. The study, conducted by Gauri Sharma and Paolo Salucci from SISSA, together with Glen Van de Ven from the University of Vienna, took a new look at one of the greatest mysteries of modern physics. According to the authors, this new research represents a step forward in our understanding of dark matter, the elusive element in our universe which has been theorised based on its demonstrable effects on heavenly bodies, but which is yet to be directly proven. This is despite any number of targeted astrophysical observations and experiments set up for the purpose in dedicated underground laboratories.

Studying dark matter in distant galaxies

Dark matter makes up approximately 84% of the mass in the cosmos: “Its dominant presence throughout the galaxies arises from the fact that the stars and hydrogen gas are moving as if governed by an invisible element” explains Gauri Sharma. Up until now, attempts to study it have focused on galaxies near to our own: “In this study, however,” she explains, “for the first time, we were seeking to observe and determine the distribution of the mass of spiral galaxies with the same morphology of those nearby, but much further away and therefore earlier by some seven billion years.

[caltrek]

Largest And Most Accurate Simulation of the Universe Created Using Supercomputers
by Benjamin Taub
February 11, 2022

https://www.iflscience.com/space/larges ... computers/

Introduction:

(IFL Science) The entire evolution of the cosmos, covering the 13.7 billion years since the Big Bang, has been accurately simulated by a supercomputer.

Describing this leviathan achievement in the Monthly Notices of the Royal Astronomical Society, researchers say that the model accurately positions the galaxies and other structures in our local universe, thereby indicating that our understanding of the forces that drive the evolution of the universe is correct.

According to the accepted model of cosmology, all astronomical events can be explained by the behavior of dark matter, which condenses into clumps known as haloes. Referred to as the Cold Dark Matter (CDM) model, this paradigm assumes that the accumulation of gases and other material around these haloes eventually leads to the formation of stars and galaxies, and has been used to explain several properties of the observable universe.

However, the study authors point out that most previous simulations using the CDM hypothesis have focused on random patches of sky rather than our own cosmic neighborhood – so they set out to determine whether or not the model could be used to accurately recreate the area of space surrounding the Milky Way galaxy.

They fed the complex physical equations that underpin the CDM model into a supercomputer called DiRAC COSmology MAchine (COSMA), located at Durham University. Based on these equations, the machine then proceeded to simulate the entire history of a patch of sky extending 600 million lightyears from our Solar System, represented by over 130 billion simulated particles.

[caltrek]

University of California - Irvine Scientists Discover How Galaxies Can Exist Without Dark Matter
February 14, 2022

https://www.eurekalert.org/news-releases/943369

Introduction:

(Eureka Alert) Irvine, Calif., Feb. 14, 2022 — In a new Nature Astronomy study (see also abstract below), an international team led by astrophysicists from the University of California, Irvine and Pomona College report how, when tiny galaxies collide with bigger ones, the bigger galaxies can strip the smaller galaxies of their dark matter — matter that we can’t see directly, but which astrophysicists think must exist because, without its gravitational effects, they couldn’t explain things like the motions of a galaxy’s stars.

It’s a mechanism that has the potential to explain how galaxies might be able to exist without dark matter – something once thought impossible.

https://www.nature.com/articles/s41550-021-01598-4

Abstract:

(Nature Astronomy) The standard cold dark matter plus cosmological constant model predicts that galaxies form within dark-matter haloes, and that low-mass galaxies are more dark-matter dominated than massive ones. The unexpected discovery of two low-mass galaxies lacking dark matter immediately provoked concerns about the standard cosmology and ignited explorations of alternatives, including self-interacting dark matter and modified gravity. Apprehension grew after several cosmological simulations using the conventional model failed to form adequate numerical analogues with comparable internal characteristics (stellar masses, sizes, velocity dispersions and morphologies). Here we show that the standard paradigm naturally produces galaxies lacking dark matter with internal characteristics in agreement with observations. Using a state-of-the-art cosmological simulation and a meticulous galaxy-identification technique, we find that extreme close encounters with massive neighbours can be responsible for this. We predict that ~30% of massive central galaxies (with at least 1011 solar masses in stars) harbour at least one dark-matter-deficient satellite (with 108–109 solar masses in stars). This distinctive class of galaxies provides an additional layer in our understanding of the role of interactions in shaping galactic properties. Future observations surveying galaxies in the aforementioned regime will provide a crucial test of this scenario.

[wjfox]

[weatheriscool]

Astronomers discover widest separation of brown dwarf pair to date
https://phys.org/news/2022-02-astronome ... -pair.html
by W. M. Keck Observatory

A team of astronomers has discovered a rare pair of brown dwarfs that has the widest separation of any brown dwarf binary system found to date.

"Because of their small size, brown dwarf binary systems are usually very close together," said Emma Softich, an undergraduate astrophysics student at the Arizona State University (ASU) School of Earth and Space Exploration and lead author of the study. "Finding such a widely separated pair is very exciting."

The gravitational force between a pair of brown dwarfs is lower than for a pair of stars with the same separation, so wide brown dwarf binaries are more likely to break up over time, making this pair of brown dwarfs an exceptional find.

The study, which is based on observations the University of California San Diego (UC San Diego) Cool Star Lab conducted with W. M. Keck Observatory on Maunakea, Hawaiʻi Island, is published in today's issue of The Astrophysical Journal Letters.

Using Keck Observatory's Near-Infrared Echellette Spectrometer, or NIRES instrument, members of the UC San Diego Cool Star Lab, including Physics Professor Adam Burgasser and graduate students Christian Aganze and Dino Hsu, obtained infrared spectra of the brown dwarf binary system, called CWISE J014611.20-050850.0AB. The data revealed the two brown dwarfs are about 12 billion miles apart, or three times the separation of Pluto from the sun. This distance confirms the unusual brown dwarf couple breaks the record for having the widest separation from each other.

"Keck's exceptional sensitivity in the infrared with this instrument was critical for our measurements," said co-author Burgasser, who leads the Cool Star Lab. "The secondary brown dwarf of this system is exceptionally faint, but with Keck we were able to obtain good enough spectral data to classify both sources and identify them as members of a rare class of blue L dwarfs."

[weatheriscool]

New 'black widow' millisecond pulsar discovered
https://phys.org/news/2022-02-black-wid ... ulsar.html
by Tomasz Nowakowski , Phys.org

An international team of astronomers reports the detection of a new millisecond pulsar (MSP) using the Green Bank Telescope (GBT). The newfound pulsar, designated PSR J1555−2908, turns out to be one of the so-called "black widow" MSPs. The finding is detailed in a paper published February 10 on arXiv.org.

The most rapidly rotating pulsars, those with rotation periods below 30 milliseconds, are known as MSPs. Researchers assume that they are formed in binary systems when the initially more massive component turns into a neutron star that is then spun up due to accretion of matter from the secondary star.

A class of extreme binary pulsars with semi-degenerate companion stars is dubbed "spider pulsars." These objects are further categorized as "black widows" if the companion has extremely low mass (less than 0.1 solar masses), while they are called "redbacks" if the secondary star is heavier.

PSR J1555−2908 was initially identified as a gamma-ray point source by NASA's Fermi spacecraft. Given that a large number of point sources in the GeV gamma-ray sky are known to be powered by pulsars, PSR J1555−2908 was perceived as a promising target to search for pulsations. Therefore, a team of astronomers led by Paul S. Ray of the U.S. Naval Research Laboratory in Washington, DC, has investigated this source with GBT, which resulted in the detection of radio pulsations.

[weatheriscool]

New insights into the formation of brown dwarfs
https://phys.org/news/2022-02-insights- ... warfs.html
by Ludwig Maximilian University of Munich

Brown dwarfs are strange celestial bodies, occupying a kind of intermediate position between stars and planets. Astrophysicists sometimes call them "failed stars" because they have insufficient mass to burn hydrogen in their cores and shine like stars. It is continually debated if the formation of brown dwarfs is simply a scaled-down version of the formation of Sun-like stars. Astrophysicists are focusing on the youngest brown dwarfs, also called proto-brown dwarfs. They are only a few thousand years old and are still in the early formation stages. They want to know if the gas and dust in these proto-brown dwarfs resemble the composition of the youngest Sun-like proto-stars.

[weatheriscool]

Scientists reveal 4.4 million galaxies in a new map
https://phys.org/news/2022-02-scientist ... axies.html
by Durham University

Durham University astronomer collaborating with a team of international scientists have mapped more than a quarter of the northern sky using the Low Frequency Array (LOFAR), a pan-European radio telescope.

The map reveals an astonishingly detailed radio image of more than 4.4 million objects and a very dynamic picture of our Universe, which now has been made public for the first time.

The vast majority of these objects are billions of light years away and are either galaxies that harbor massive black holes or are rapidly growing new stars. Rarer objects that have been discovered include colliding groups of distant galaxies and flaring stars within the Milky Way.

To produce the map, scientists deployed state-of-the-art data processing algorithms on high performance computers all over Europe to process 3,500 hours of observations that occupy 8 petabytes of disk space—the equivalent to roughly 20,000 laptops.

This data release, which is by far the largest from the LOFAR Two-metre Sky Survey, presents about a million objects that have never been seen before with any telescope and almost four million objects that are new discoveries at radio wavelengths.

[weatheriscool]

Distant supergiant star investigated in detail
https://phys.org/news/2022-03-distant-s ... -star.html
by Tomasz Nowakowski , Phys.org

Astronomers from the University of La Laguna, Spain and elsewhere have performed spectroscopic observations of an early B-type supergiant star known as 2MASS J20395358+4222505. Results of this observational campaign, published February 23 on the arXiv pre-print server, deliver important insights into the nature of this object.

Supergiants are evolved high-mass stars, larger and more luminous than main-sequence stars. Studying such objects is crucial for improving our understanding of stellar evolution; however, their observation is complicated due to the fact that they are relatively far away, tend to be born in binary or multiple systems, and are associated with dense clouds of interstellar material.

2MASS J20395358+4222505 (or J20395358+4222505 for short) is a highly reddened supergiant of spectral type B0 I in the vicinity of the Cygnus OB2 association. The star is located some 5,730 light years away from the Earth and has an absolute magnitude of approximately -9.8, which makes it one of the most luminous objects among the B supergiants.

[weatheriscool]

SpaceX hints at replacing Russian space station services

By Chelsea Gohd published 5 days ago
https://www.space.com/spacex-elon-musk- ... socialflow

Could SpaceX replace Russia in space?

Last week, Russia invaded Ukraine in a series of attacks that sparked some of the most intense conflict in Europe in decades. Most recently, on Sunday night (Feb. 27) Russian President Vladimir Putin declared a nuclear alert, a move that only furthered international concern. With tensions rising ever higher, companies and countries around the world are breaking ties with Russia in space.

SpaceX recently activated Starlink internet services in Ukraine, showing support for the nation under attack. With the company already ferrying astronauts to and from the International Space Station, reducing NASA's dependence on Russian Soyuz rides, it seems more possible than ever that SpaceX could fully replace the need for Russia's Soyuz capsule.

[wjfox]

[weatheriscool]

NASA's NICER telescope sees hot spots merge on a magnetar
https://phys.org/news/2022-03-nasa-nice ... merge.html
by Francis Reddy, NASA's Goddard Space Flight Center

For the first time, NASA's Neutron star Interior Composition Explorer (NICER) has observed the merging of multimillion-degree X-ray spots on the surface of a magnetar, a supermagnetized stellar core no larger than a city.

"NICER tracked how three bright, X-ray-emitting hot spots slowly wandered across the object's surface while also decreasing in size, providing the best look yet at this phenomenon," said George Younes, a researcher at George Washington University in Washington and NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The largest spot eventually coalesced with a smaller one, which is something we haven't seen before."

This unique set of observations, described in a paper led by Younes and published Jan. 13 in The Astrophysical Journal Letters, will help guide scientists to a more complete understanding of the interplay between the crust and magnetic field of these extreme objects.

A magnetar is a type of isolated neutron star, the crushed core left behind when a massive star explodes. Compressing more mass than the Sun's into a ball about 12 miles (20 kilometers) across, a neutron star is made of matter so dense that a teaspoonful would weigh as much as a mountain on Earth.

[caltrek]

Researchers Find the Largest Molecule Ever Spotted in Planet-forming Disk
by Carson McCullough
March 8, 2022

https://www.courthousenews.com/research ... ming-disk/

Introduction:

(Courthouse News) — For the first time ever, researchers have found dimethyl ether — a grandfather molecule to some essential life building blocks in the universe — in a planet-forming disk over 400 light years away.

Dimethyl ether, while commonly used here on Earth to help with organic synthesis, has proven somewhat illusive in the expanse of space. A larger molecule with nine atoms and the most chemically simple form of ether we know of, dimethyl ether has never been observed in the giant gaseous disks that form planets. They’re quite commonly found in star-forming clouds, but for a long time experts assumed they would never be able to find them in planet-forming disks.

That all changed on Tuesday, however, when researchers revealed in a study in Astronomy & Astrophysics they had found the molecule in one of those disks for the first time.

"It is really exciting to finally detect these larger molecules in disks,” said Alice Booth, researcher at Leiden Observatory and co-author of the study. “For a while we thought it might not be possible to observe them.”

Researchers made this discovery using instruments from the Atacama Large Millimeter/submillimeter Array (ALMA) at the European Southern Observatory in Chile. They found dimethyl ether in a disk close to the star IRS 48, a relatively young star nestled in the Ophiuchus constellation about 444 light years from Earth.

[raklian]

[caltrek]

Orbits Around Supermassive Black Holes Might Be Like A "Giant Game Of Billiards"
by Dr Alfredo Carpineti
March 11, 2022

https://www.iflscience.com/space/orbits ... billiards/

Introduction:

(IFL Science) At the center of almost every galaxy, there is a supermassive black hole, weighing millions if not billions of times the mass of our Sun. If a new paper is correct, around some of those enormous black holes there are many smaller ones, interacting and merging together.

As reported in Nature, the environment around supermassive black holes could be favorable for stellar-sized black hole collisions, like GW190521. This specific event was peculiar to research because it showed two black holes orbiting each other in a non-circular orbit (geometrically eccentric), something never seen before.

The merger was also the heaviest to date, and the first with a potentially light counterpart, creating a whole flurry of excitement and uncertainties. The international team argues that supermassive black holes could be crucial to make these mergers more likely.

“In these environments the typical velocity and density of black holes is so high that smaller black holes bounce around as in a giant game of billiards and wide circular binaries cannot exist,” co-author Professor Bence Kocsis from the University of Oxford, said in a statement.

[wjfox]

Red Dwarfs Will Be Humanity’s Last Home Before the Universe Dies

4 hours ago

When everything else is gone, we could survive for trillions of years around them.

https://antoniomelonio-cosmos.medium.com/red-dwarfs-will-be-humanitys-last-home-before-the-universe-dies-b567fcfa6081

[weatheriscool]

Space Based Starshades Will Make Large Ground Telescopes the Most Powerful Exoplanet Finders
March 14, 2022 by Brian Wang

Hybrid observatories will combine a 100 meter diameter starshade in space with a telescope on the ground. The Hybrid Observatory for Earth-like Exoplanets (HOEE) would convert the largest ground-based telescopes now under construction (Giant Magellan Telescope, Thirty Meter Telescope, and Extremely Large Telescope) into the most powerful planet finders yet designed. No other proposed equipment can match the angular resolution (image sharpness), sensitivity (ability to see faint objects in a given time), or contrast (ability to see faint planets near bright stars).

Above- Graphic depiction of Hybrid Observatory for Earth-like Exoplanets (HOEE) Credits: John Mather

The large telescope is needed because Earth-like planets are extremely faint. The starshade is needed to block the glare of the host stars; the sun is 10 billion times brighter than the Earth at visible wavelengths. A starshade in an astro-stationary orbit would match position and velocity with the moving telescope, and cast a dark shadow of the star, without blocking the light of its planets. Active propulsion would maintain alignment during the observation. Adaptive optics in the telescope would compensate for atmospheric distortion of the incoming images.

https://www.nextbigfuture.com/2022/03/s ... anets.html

[Yuli Ban]

They call space ‘the final frontier’ but it’s starting to look more like Interstate 405 on Memorial Day Weekend. At least that’s what the Space Force fears will happen as the public and commercial sectors send more satellites into the space between Earth and the Moon. To keep a closer eye on this burgeoning lane of space traffic, America’s newest military branch wants to start a Cislunar Highway Patrol System, or CHPS, for short, just like the California Highway Patrol made famous by the 1970s TV show ‘CHiPs.”

“Until now the United States space mission extended 22,000 miles above earth,” the Air Force Research Laboratory said in a recent YouTube video, which was first reported by Ars Technica. “That was then, this is now.”