Space News and Discussions

[weatheriscool]

Supermassive black hole seen at the center of our galaxy
Source: Washington Post

Astronomers on Thursday unveiled the first image of a supermassive black hole that roils the center of our galaxy, its gravity so powerful that it bends space and time and forms a glowing ring of light with eternal darkness at the core. The black hole, seen from Earth near the constellation Sagittarius, has a mass equal to more than 4 million suns.


An image released by the Event Horizon Telescope Collaboration on May 12 shows a black hole at the center of the Milky Way galaxy. (AP)

Feryal Ozel, a University of Arizona astronomer, described the achievement as "the first direct image of the gentle giant in the center of our galaxy.” “We find a bright ring surrounding the black hole shadow," she said. "It seems that black holes like doughnuts.” The image was captured by a global consortium of astronomical observatories, known as the Event Horizon Telescope. Three years ago the project produced the first image of a black hole, in the galaxy Messier 87.

The black hole at the center of the Milky Way is more than a thousand times smaller than the one in Messier 87. But cosmically speaking, it is the one closest to home. The unveiling of the image at the National Press Club in Washington was part of simultaneous media events on multiple continents. The image was kept under wraps pending an unveiling at precisely 9:07 a.m. Eastern time.

“They are the most mysterious objects in the universe, and they hold the keys to large-scale structure in the observable cosmos,” said Sheperd Doeleman, an astronomer at the Harvard-Smithsonian Center for Astrophysics and director of the Event Horizon Telescope, in an interview in advance of Thursday’s briefing.

Read more: https://www.washingtonpost.com/science/ ... milky-way/

[Yuli Ban]

Supermassive black hole seen at the center of our galaxy
Source: Washington Post

Astronomers on Thursday unveiled the first image of a supermassive black hole that roils the center of our galaxy, its gravity so powerful that it bends space and time and forms a glowing ring of light with eternal darkness at the core. The black hole, seen from Earth near the constellation Sagittarius, has a mass equal to more than 4 million suns.


An image released by the Event Horizon Telescope Collaboration on May 12 shows a black hole at the center of the Milky Way galaxy. (AP)

Feryal Ozel, a University of Arizona astronomer, described the achievement as "the first direct image of the gentle giant in the center of our galaxy.” “We find a bright ring surrounding the black hole shadow," she said. "It seems that black holes like doughnuts.” The image was captured by a global consortium of astronomical observatories, known as the Event Horizon Telescope. Three years ago the project produced the first image of a black hole, in the galaxy Messier 87.

The black hole at the center of the Milky Way is more than a thousand times smaller than the one in Messier 87. But cosmically speaking, it is the one closest to home. The unveiling of the image at the National Press Club in Washington was part of simultaneous media events on multiple continents. The image was kept under wraps pending an unveiling at precisely 9:07 a.m. Eastern time.

“They are the most mysterious objects in the universe, and they hold the keys to large-scale structure in the observable cosmos,” said Sheperd Doeleman, an astronomer at the Harvard-Smithsonian Center for Astrophysics and director of the Event Horizon Telescope, in an interview in advance of Thursday’s briefing.

Read more: https://www.washingtonpost.com/science/ ... milky-way/

Wowee wow!!!


Just makes me wish we could visit one to see one up close (safely)

[raklian]

For those of you who are Twitter-inclined, read this excellent thread about this discovery.

[raklian]

Comparison of the sizes of two black holes: M87 and Sagittarius A



https://www.eso.org/public/images/eso2208-eht-mwe/

[raklian]

Major breakthrough!

Scientists Grow Plants in Lunar Soil

Scientists at the University of Florida have made a breakthrough discovery — decades in the making — that could both enable space exploration and benefit humanity. “Here we are, 50 years later, completing experiments that were started back in the Apollo labs,” said Robert Ferl, a professor in the Horticultural Sciences department at the University of Florida, Gainesville, and a communicating author on a paper published on May 12, 2022, in Communications Biology. “We first asked the question of whether plants can grow in regolith. And second, how might that one day help humans have an extended stay on the Moon.”

The answer to the first question is a resounding yes. Plants can grow in lunar regolith. They were not as robust as plants grown in Earth soil, or even as those in the control group grown in a lunar simulant made from volcanic ash, but they did indeed grow. And by studying how the plants responded in the lunar samples, the team hopes to go on to answer the second question as well, paving the way for future astronauts to someday grow more nutrient-rich plants on the Moon and thrive in deep space.

https://www.nasa.gov/feature/biological ... m-the-moon

[weatheriscool]

Black hole winds are no longer as they used to be
https://phys.org/news/2022-05-black-hole-longer.html
by Italian National Institute for Astrophysics

During the first billion years of the universe, winds blown by supermassive black holes at the centers of galaxies were much more frequent and more powerful than those observed in today's galaxies, some 13 billion years later. Such winds were so mighty that they slowed down the growth of the supermassive black holes from which they originate. These are the results of a study led by three researchers from the Italian National Institute for Astrophysics (INAF) in Trieste, published today in the journal Nature.

The work is based on the observations of 30 quasars observed with the Very Large Telescope (VLT) at ESO's Paranal Observatory in Chile. Quasars are extremely bright, point-like sources at the cores of distant galaxies, whose emission arises from the intense activity of the central supermassive black holes sucking in the surrounding matter. The host galaxies of these quasars were observed around cosmic dawn, when the universe was between 500 million and 1 billion years old.

"For the first time, we measured the fraction of quasars in the young universe exhibiting black hole winds," says Manuela Bischetti, INAF researcher in Trieste and first author of the new study. "Unlike what we observe in the universe closer to us, we discovered that black hole winds in the young universe are very frequent, have high speeds up to 17 percent of the speed of light, and inject large amounts of energy into their host galaxy."

About half of the quasars observed in this research show black hole winds, which are much more frequent and 20 times more powerful than the ones known in the quasars of the more nearby cosmos when the universe was around 4 billion years old.

"Observations of black holes in the young universe show that they grow much faster than their host galaxies, whereas in the local universe, we know that black holes and galaxies co-evolve," adds co-author Chiara Feruglio, INAF researcher in Trieste. "This implies that a mechanism must have acted at some point in the universe, slowing down black hole growth. Our observations enabled us to identify this mechanism in the black hole winds produced when the universe was 0.5 to 1 billion years old."

[caltrek]

"Gold Standard" Star Holds Record Number of Elements
by Morgan Sherburne
May 16, 2022

(Futurity) In our sun’s neighborhood of the Milky Way galaxy is a relatively bright star, and in it, astronomers have been able to identify the widest range of elements in a star beyond our solar system.

Identifying these elements in a single star will help astronomers understand what’s called the “rapid neutron capture process,” or one of the major ways heavy elements in the universe were created.

“To the best of my knowledge, that’s a record for any object beyond our solar system. And what makes this star so unique is that it has a very high relative proportion of the elements listed along the bottom two-thirds of the periodic table. We even detected gold,” says lead author Ian Roederer, an astronomer at the University of Michigan.

“These elements were made by the rapid neutron capture process. That’s really the thing we’re trying to study: the physics in understanding how, where, and when those elements were made.”

Read more here: https://www.futurity.org/hd-222925-gold ... 2739612-2/

For a more technical discussion, read here: https://arxiv.org/abs/2205.03426

[caltrek]

Fascinating Quadruple Star System Might Be Pathway To Rare Supernova
by Dr Alfredo Carpineti
May 16, 2022

Introduction:

(IFL Science) The double-binary star system HD74438 was a peculiar find when it was discovered in 2017. Two pairs of very close-binary stars orbit each other in a rare quadruple system. This is already incredibly cool but astronomers believe there is more. Simulations suggest that these kinds of set-ups might lead to a specific and rare type of supernova.

One binary pair orbits each other every 20 days or so. The other every four days. Each pair orbit each other in about six years, making HD74438 the quadruple system with the shortest period. It's also the youngest, with an estimated age of 43 million years. But simulations published in Nature Astronomy look at the future of the system rather than the past.

The outer binary pair is changing the eccentricity of the inner one, making the orbit less like a circle and more oval. The simulations show that this effect might lead to one or more stellar collisions, and from there to white dwarfs going supernova.

"A star like our Sun will end its life as a small dense dead star known as a white dwarf, and the mass of white dwarfs cannot go above the so-called Chandrasekhar limit (about 1.4 times the mass of the sun)," co-author Associate Professor Karen Pollard from the University of Canterbury said in a statement.

"If it does, because of mass transfer or merger events, it can collapse and produce a thermonuclear supernova. Interestingly, 70% to 85% of all thermonuclear supernovae are now suspected to result from the explosion of white dwarfs with sub-Chandrasekhar masses. As a result of mass transfer or mergers, these white dwarf stars can explode as a thermonuclear supernova explosion."

Read more here: https://www.iflscience.com/space/fascin ... supernova/

[caltrek]

Merging Supermassive Black Holes (SMBHs) Gives us a New Way to Measure the Universe
by Matt Williams
May 17, 2022

Extract:

(Universe Today) A pair of researchers from Columbia University (Zoltán Haiman and Jordy Davelaar) announced a new and potentially easier way to study black holes. In particular, their method could enable the study of black holes smaller than M87* in galaxies more distant than the M87 galaxy.
…
As Haiman and Davelaar explain, viewing a binary black hole system edge-on as one passes in front of the other (aka. transits), astronomers will be able to use the gravitational force of the closest BH to magnify the bright disk of the more distant one. However, these observations will also reveal another interesting feature. As two BHs pass in front of each other, said Haiman and Davelaar, there will be a distinctive dip in brightness corresponding to the “shadow” of the more distant black hole.
…
The detection of this shadow could have immense implications for astrophysicists and quantum physicists alike. Astrophysicists have been looking for these shadows as part of an ongoing effort to test General Relativity under the most extreme conditions and environments. These tests could lead to a new understanding of how gravity and quantum forces interact, which would allow physicists to finally resolve how the four fundamental forces of nature work together – electromagnetic, weak nuclear forces, strong nuclear forces, and gravity.
…
Haiman and Davelaar are currently looking for other telescope data to confirm the Kepler observations and verify that “Spikey” (their name given to a suspected pair of SMBHs) really is harboring a pair of merging black holes. If and when their technique is confirmed, it is likely to be applied to the roughy 150 pairs of merging SMBHs that have been observed but are still awaiting confirmation. In the coming years, next-generation telescopes will be coming online that will allow for more opportunities to test this technique.

Examples include the Vera C. Rubin Observatory, a massive telescope in Chile scheduled to open later this year. Once operational, Rubin will conduct the 10-year Legacy Survey of Space and Time (LSST) that will include the observation of more than 100 million SMBHs. By 2030, NASA’s Laser Interferometry Space Antenna, a space-based gravitational wave detector, will also come online and enable even more opportunities to study merging black holes. With so many candidates available for study, scientists shouldn’t have to wait too long for a breakthrough.

Source: https://www.universetoday.com/155907/me ... ore-155907

[weatheriscool]

New spin on galaxy rotation saves controversial gravity theory
https://phys.org/news/2022-05-galaxy-ro ... heory.html
by University of St Andrews

An international group of astronomers, led by a physicist at the University of St Andrews, has revived an alternative gravity theory.

Headed by Dr. Indranil Banik of the School of Physics and Astronomy at St Andrews, the study revealed a high predicted rotation speed of gas in a dwarf galaxy consistent with the previously debunked theory known as Milgromian Dynamics (MOND).

An earlier study of the rotation speed of gas in the dwarf galaxy AGC 114905 (Mancera Pina et al, 2022) found that the gas rotated very slowly and claimed the MOND theory was dead.

Such theories are essential in understanding our universe because, according to known physics, galaxies rotate so quickly they should fly apart. MOND, a controversial alternative to General Relativity, the prevailing Einstein-inspired understanding of the phenomenon of gravity that requires dark matter to hold galaxies together; does not require dark matter. As dark matter has never been detected despite decades of very sensitive searches, various theories have been put forward to explain what holds galaxies together, and debate rages over which is right. The very low rotation speed reported in the Mancera Pina et al study is inconsistent with predictions in a universe governed by General Relativity with large amounts of dark matter.

Dr. Banik's group argues that the high predicted rotation speed in the MOND gravity theory is consistent with observations if the inclination of the galaxy is overestimated.

[weatheriscool]

New discovery about distant galaxies: Stars are heavier than we thought
https://phys.org/news/2022-05-discovery ... avier.html
by Niels Bohr Institute

A team of University of Copenhagen astrophysicists has arrived at a major result regarding star populations beyond the Milky Way. The result could change our understanding of a wide range of astronomical phenomena, including the formation of black holes, supernovae and why galaxies die.

For as long as humans have studied the heavens, how stars look in distant galaxies has been a mystery. In a study published today in The Astrophysical Journal, a team of researchers at the University of Copenhagen's Niels Bohr Institute is challenging previous understandings of stars beyond our own galaxy.

Since 1955, it has been assumed that the composition of stars in the universe's other galaxies is similar to that of the hundreds of billions of stars within our own—a mixture of massive, medium mass and low mass stars. But with the help of observations from 140,000 galaxies across the universe and a wide range of advanced models, the team has tested whether the same distribution of stars apparent in the Milky Way applies elsewhere. The answer is no. Stars in distant galaxies are typically more massive than those in our "local neighborhood." The finding has a major impact on what we think we know about the universe.

[wjfox]

Long journey to Europa, an icy moon of Jupiter, begins for ASU-built camera

27 May 2022

After months of testing, an ASU-designed and -built instrument to measure the surface temperature of a moon of Jupiter has arrived at NASA's Jet Propulsion Laboratory in Southern California. There it will join eight other instruments and become an integral part of the agency's Europa Clipper spacecraft.

The instrument is the Europa Thermal Emission Imaging System [LINK] (E-THEMIS) led by Regents Professor Philip Christensen of Arizona State University’s School of Earth and Space Exploration.

The Europa Clipper is a robotic spacecraft sent to investigate Jupiter's ice-shrouded moon Europa. It is planned to launch on a SpaceX Falcon Heavy [LINK] rocket in October 2024 and arrive at Jupiter in April 2030 after making flybys of Mars in 2025 and Earth in 2026. These planetary flybys use the masses of Mars and Earth to boost the spacecraft's velocity so it can reach the Jupiter system.

After entering orbit at Jupiter, the spacecraft will make about 50 flybys of Europa to investigate whether the moon could harbor conditions suitable for life.

E-THEMIS is an infrared camera designed to map temperatures across Europa’s surface. Its images, taken in three heat-sensitive bands, will help scientists find clues about Europa’s geological activity, including regions where the moon's presumed ocean may lie near the surface. Although Europa is slightly smaller than Earth's moon, scientists think its ocean may hold twice the volume of Earth's oceans.

https://www.eurekalert.org/news-releases/954238

[weatheriscool]

NASA's Ingenuity Mars Helicopter captures video of record flight
https://phys.org/news/2022-05-nasa-inge ... tures.html
by Jet Propulsion Laboratory

Imagery has come down from Mars capturing a recent flight in which the rotorcraft flew farther and faster than ever before.

The Ingenuity Mars Helicopter's black-and-white navigation camera has provided dramatic video of its record-breaking 25th flight, which took place on April 18. Covering a distance of 2,310 feet (704 meters) at a speed of 12 mph (5.5 meters per second), it was the Red Planet rotorcraft's longest and fastest flight to date. (Ingenuity is currently preparing for its 29th flight.)

"For our record-breaking flight, Ingenuity's downward-looking navigation camera provided us with a breathtaking sense of what it would feel like gliding 33 feet above the surface of Mars at 12 miles per hour," said Ingenuity team lead Teddy Tzanetos of NASA's Jet Propulsion Laboratory in Southern California.

[wjfox]

[weatheriscool]

NASA's DAVINCI mission to take the plunge through massive atmosphere of Venus
https://phys.org/news/2022-06-nasa-davi ... ssive.html
by Nancy Neal Jones, NASA

In a paper recently published in The Planetary Science Journal, NASA scientists and engineers give new details about the agency's Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging (DAVINCI) mission, which will descend through the layered Venus atmosphere to the surface of the planet in mid-2031. DAVINCI is the first mission to study Venus using both spacecraft flybys and a descent probe.

DAVINCI, a flying analytical chemistry laboratory, will measure critical aspects of Venus's massive atmosphere-climate system for the first time, many of which have been measurement goals for Venus since the early 1980s. It will also provide the first descent imaging of the mountainous highlands of Venus while mapping their rock composition and surface relief at scales not possible from orbit. The mission supports measurements of undiscovered gases present in small amounts and the deepest atmosphere, including the key ratio of hydrogen isotopes—components of water that help reveal the history of water, either as liquid water oceans or steam within the early atmosphere.

The mission's carrier, relay and imaging spacecraft (CRIS) has two onboard instruments that will study the planet's clouds and map its highland areas during flybys of Venus and will also drop a small descent probe with five instruments that will provide a medley of new measurements at very high precision during its descent to the hellish Venus surface.

"This ensemble of chemistry, environmental, and descent imaging data will paint a picture of the layered Venus atmosphere and how it interacts with the surface in the mountains of Alpha Regio, which is twice the size of Texas," said Jim Garvin, lead author of the paper in the Planetary Science Journal and DAVINCI principal investigator from NASA's Goddard Space Flight Center in Greenbelt, Maryland. "These measurements will allow us to evaluate historical aspects of the atmosphere as well as detect special rock types at the surface such as granites while also looking for tell-tale landscape features that could tell us about erosion or other formational processes."

[weatheriscool]

Three Chinese astronauts arrive at space station
https://phys.org/news/2022-06-chinese-a ... ation.html
by Ludovic Ehret

A rocket carrying three astronauts on a mission to China's new space station was launched Sunday.

Three Chinese astronauts arrived at the country's space station on Sunday, the Chinese space agency for human flights said, the latest stride in Beijing's aim to become a major space power.

The trio blasted off in a Long March-2F rocket at 0244 GMT from the Jiuquan launch center in northwestern China's Gobi desert, reported state broadcaster CCTV.

The team is tasked with "completing in-orbit assembly and construction of the space station", as well as "commissioning of equipment" and conducting scientific experiments, state-run CGTN said Saturday.

The astronauts entered the central module of the Tiangong station at around 1250 GMT, the China Manned Space Agency (CMSA) said. The journey took about "seven hours of flight", CCTV reported.

Tiangong, which means "heavenly palace", is expected to become fully operational by the end of the year.

China's heavily promoted space program has already seen the nation land a rover on Mars and send probes to the Moon.

The Shenzhou-14 crew is led by air force pilot Chen Dong, 43, the three-person crew's main challenge will be connecting the station's two lab modules to the main body.

Dong, along with fellow pilots Liu Yang and Cai Xuzhe, will become the second crew to spend six months aboard the Tiangong after the last returned to earth in April following 183 days on the space station.

[weatheriscool]

Bezos's Blue Origin makes 5th crewed flight into space

In this still image taken from a Blue Origin broadcast, a Blue Origin New Shepard rocket launches from Launch Site One in West Texas for the company's fifth crewed mission.

Jeff Bezos's company Blue Origin flew six tourists into space for a 10-minute ride Saturday, successfully carrying out its fifth crewed mission.

The white spacecraft called New Shepard lifted off with a roar from a desert spot in west Texas at 8:26 local time (1326 GMT).

The crew hooted with glee as the rocket reached space, a Blue Origin webcast showed.

The flight included engineer Katya Echazarreta, who at 26 became the youngest American woman in space. The Guadalajara native also became the first Mexican-born woman to go into space.

Her spot was sponsored by Space for Humanity, a program which seeks to democratize access to space and selected her from among 7,000 candidates.

The crew also included the first Brazilian to go into space, Victor Correa Hespanha, as well as businessmen Hamish Harding, Jaison Robinson, Victor Vescovo and Evan Dick.

Dick also flew on New Shepard's third crewed flight in December.

Ticket prices are a closely guarded secret.

The gumdrop-shaped capsule holding the crew detached from the rocket once the latter took them into the heavens.

https://phys.org/news/2022-06-bezos-blu ... light.html

[caltrek]

Hubble Space Telescope Captures Largest Near-infrared Image to Find Universe’s Rarest Galaxies
June 6, 2022

Introduction:

(EurekAlert) TORONTO, ON – An international team of scientists today released the largest near-infrared image ever taken by NASA’s Hubble Space Telescope, enabling astronomers to map the star-forming regions of the universe and learn how the earliest, most distant galaxies originated. Named 3D-DASH, this high-resolution survey will allow researchers to find rare objects and targets for follow-up observations with the recently launched James Webb Space Telescope (JWST) during its decades-long mission.

A preprint of the paper to be published in The Astrophysical Journal is available on arXiv (https://arxiv.org/abs/2206.01156 ).

“Since its launch more than 30 years ago, the Hubble Space Telescope has led a renaissance in the study of how galaxies have changed in the last 10-billion years of the universe,” says Lamiya Mowla, Dunlap Fellow at the Faculty of Arts & Science’s Dunlap Institute for Astronomy & Astrophysics at the University of Toronto and lead author of the study. “The 3D-DASH program extends Hubble’s legacy in wide-area imaging so we can begin to unravel the mysteries of the galaxies beyond our own.”

For the first time, 3D-DASH provides researchers with a complete near-infrared survey of the entire COSMOS field, one of the richest data fields for extragalactic studies beyond the Milky Way. As the longest and reddest wavelength observed with Hubble – just past what is visible to the human eye – near-infrared means astronomers are better able to see the earliest galaxies that are the farthest away.

Astronomers also need to search a vast area of the sky to find rare objects in the universe. Until now, such a large image was only available from the ground and suffered from poor resolution, which limited what could be observed. 3D-DASH will help to identify unique phenomena like the universe’s most massive galaxies, highly active black holes, and galaxies on the brink of colliding and merging into one.

Read more here: https://www.eurekalert.org/news-releases/954900

[weatheriscool]

Cosmological gravitational waves: A new approach to reach back to the Big Bang

by International School of Advanced Studies (SISSA)

Operating observatories around the globe target sky regions characterized by low contamination from Galactic radiation, looking for the imprint of Cosmological Gravitational Waves (CGWs) produced during Inflation, the mysterious phase of quasi-exponential expansion of space in the very early Universe. A new study by the POLARBEAR collaboration, led by SISSA for the part concerning the interpretation for Cosmology and published in the Astrophysical Journal, provides a new correction algorithm that allows researchers to almost double the amount of reliable data acquired in such observatories, thus giving access to uncharted territory of the signal produced from CGWs and bringing us closer to the Big Bang.

"According to the current understanding in Cosmology, just after the Big Bang the Universe was very small, dense and hot. In 10-35 seconds, it stretched by a factor of 1030," Carlo Baccigalupi, coordinator of the Astrophysics & Cosmology group at SISSA, explains. "This process, known as Inflation, produced Cosmological Gravitational Waves (CGW) that can be detected through the polarization of the Cosmic Microwave Background (CMB), the leftover radiation from the Big Bang. The POLARBEAR experiment, which SISSA is part of, looks for such signals using the Huan Tran Telescope in the Atacama Desert of northern Chile in the Antofagasta Region."

The analysis of data acquired by the POLARBEAR Observatory is a complex pipeline where reliability of measurements represents a most delicate and key factor. "The CGWs excite only a tiny fraction of the CMB polarization signal, better known as B-modes," Nicoletta Krachmalnicoff, researcher at SISSA, and Davide Poletti, previously at the same institute, explain. "They are very difficult to measure, in particular because of the contamination of the signal due to the emissions of the diffuse Galactic gas. This must be removed with exquisite accuracy to isolate the unique contribution of CGWs."

https://phys.org/news/2022-06-cosmologi ... h-big.html

[weatheriscool]

NASA's Europa Clipper Mission completes main body of the spacecraft
https://phys.org/news/2022-06-nasa-euro ... -main.html
by JPL/NASA

The main body of NASA's Europa Clipper spacecraft has been delivered to the agency's Jet Propulsion Laboratory in Southern California. Over the next two years there, engineers and technicians will finish assembling the craft by hand before testing it to make sure it can withstand the journey to Jupiter's icy moon Europa.

The spacecraft body is the mission's workhorse. Standing 10 feet (3 meters) tall and 5 feet (1.5 meters) wide, it's an aluminum cylinder integrated with electronics, radios, thermal loop tubing, cabling, and the propulsion system. With its solar arrays and other deployable equipment stowed for launch, Europa Clipper will be as large as an SUV; when extended, the solar arrays make the craft the size of a basketball court. It is the largest NASA spacecraft ever developed for a planetary mission.