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Cape Cod’s water is turning “pea-soup green”—and after decades of scientific detective work, we know why.

This week the Moon occults Beta Virginis, then Antares. The last star of the Summer Triangle finally rises before bedtime. On the other side of the sky, the Arch of Spring sinks low.

The post This Week's Sky at a Glance, May 17 – 26 appeared first on Sky & Telescope.

This summer marks the ten-year anniversary of the electromagnetic levitation facility on the International Space Station.

Image: Captured on 7 May 2024, this Copernicus Sentinel-2 image shows part of New Zealand’s North Island.

Explore this mission kit to learn more about EarthCARE – ESA’s new mission that will shed new light on the role that clouds and aerosols play in regulating Earth’s climate.

This oddly shaped cloud of dusty gas is shaped by the winds and radiation from nearby stars.

The post Cosmic "Hand" Reaches for the Stars appeared first on Sky & Telescope.

Analysis of pollen in sediment cores from a large lake in Greece shows that nomadic livestock herders took over the region after the collapse of the Western Roman Empire

Analysis of pollen in sediment cores from a large lake in Greece shows that nomadic livestock herders took over the region after the collapse of the Western Roman Empire

A long time ago, in two galaxies far, far away, two massive black holes merged. This happened when the Universe was only 740 million years old. A team of astronomers used JWST to study this event, the most distant (and earliest) detection of a black hole merger ever.

Such collisions are fairly commonplace in more modern epochs of cosmic history and astronomers know that they lead to ever-more massive black holes in the centers of galaxies. The resulting supermassive black holes can contain millions of billions of solar masses. They affect the evolution of their galaxies in many ways.

Using JWST and HST, astronomers have found behemoth black holes earlier and earlier in cosmic time, within the first billion years of the Universe’s history. That raises the question: how did they get so massive so fast? Black holes accrete matter as they grow, and for the most supermassive ones, their colliding galaxies are part of that matter-harvesting history.

What JWST Shows Us about Early Black Holes Merging

The most recent JWST observations focused on a system called ZS7. It’s a galaxy merger where two very early systems come together, complete with colliding black holes. This is not something astronomers can detect with ground-based telescopes. The merger itself lies quite far away. Plus, the expansion of the Universe stretches its light into the infrared part of the electromagnetic spectrum. That makes it inaccessible from Earth’s surface. However, infrared is detectable with JWST’s Near-infrared Spectrometer (NIRSpec). It can find signatures of mergers in the early Universe, according to astronomer Hannah Übler of the University of Cambridge in the United Kingdom.

Zeroing in on the ZS7 galaxy system and the colliding black holes. Courtesy: The field in which the ZS7 galaxy merger was observed by JWST. Courtesy ESA/Webb, NASA, CSA, J. Dunlop, D. Magee, P. G. Pérez-González, H. Übler, R. Maiolino, et. al

“We found evidence for very dense gas with fast motions in the vicinity of the black hole, as well as hot and highly ionized gas illuminated by the energetic radiation typically produced by black holes in their accretion episodes,” said Übler, who is lead author on a paper about the discovery. “Thanks to the unprecedented sharpness of its imaging capabilities, Webb also allowed our team to spatially separate the two black holes.”

Those black holes are pretty massive: one contains about 50 million solar masses. The other probably has about the same mass, but it’s hard to tell because it’s embedded in a dense gas region. The stellar masses of the galaxies puts them in about the same stellar-mass population as the nearby Large Magellanic Cloud, according to astronomer Pablo G. Pérez-González of the Centro de Astrobiología (CAB), CSIC/INTA, in Spain. “We can try to imagine how the evolution of merging galaxies could be affected if each galaxy had one supermassive black hole as large or larger than the one we have in the Milky Way”.

Other Implications of Black Hole Mergers at Cosmic Dawn

The analysis of the JWST observations reinforces the idea that mergers are an important way for black holes to grow. That’s particularly true in the early Universe, according to Ühler. “Together with other Webb findings of active, massive black holes in the distant Universe, our results also show that massive black holes have been shaping the evolution of galaxies from the very beginning.”

Many active galactic nuclei (AGN) in the very early Universe are associated with somewhat massive black holes. These are likely part of a general merger process in early epochs. Astronomers want to know when these mergers began. That would help them pinpoint the growth of the central supermassive black holes. Mergers of that kind are a likely route for the growth of black holes so early in cosmic time.

An artist’s impression of two merging black holes. Image: NASA/CXC/A. Hobart

That’s why astronomers are so anxious to spot them with JWST and future telescopes. They hold the key to understanding the evolution of galaxies and black holes in the infancy of the Universe. Uhler and her team members point this out in their paper, saying: “Our results seem to support a scenario of an imminent massive black hole merger in the early universe, highlighting this as an additional important channel for the early growth of black holes. Together with other recent findings in the literature, this suggests that massive black hole merging in the distant universe is common.”

Of course, these mergers don’t just generate light we can detect with JWST. They also generate very faint gravitational waves. But, there’s hope of detecting those waves with the upcoming Laser Interferometer Space Antenna (LISA). It will be in place in the 2030s and should be able to focus on the types of galaxy and black-hole mergers JWST is detecting today in infrared light.

For More Information

Webb Detects Most Distant Black Hole Merger to Date
GA-NIFS: JWST Discovers an Offset AGN 740 Million Years After the Big Bang

The post Webb Sees Black Holes Merging Near the Beginning of Time appeared first on Universe Today.

During a close flyby of Europa, the Juno spacecraft was at an altitude of just 330 kilometers (220 miles) above the moon's surface. It caught some awesome images, too.

The Sun has been vying for attention these last couple of weeks. First with the appearance of a fabulous complex sunspot region and then with a plethora of solar flares. On the 14th May, yet another was released, this time an X8.7 class flare from the same complex sunspot regions. It was significantly more powerful than the flare that set off the aurora displays which enchanted much of the planet but alas it was not pointing toward the Earth (

2023 image capturing the Sun’s glint in between a cloudy stretch of the south Atlantic Ocean off the coast of Argentina.Credits: NASA

NASA was named Thursday as the 2023 Best Place to Work in the Federal Government – large agency – for the 12th year in a row by the Partnership for Public Service. The title serves as a reflection of employee satisfaction with the workplace and functioning of the overall agency as NASA explores the unknown and discovers new knowledge for the benefit of humanity.

“Once again, NASA has shown that with the world’s finest workforce, we can reach the stars,” said NASA Administrator Bill Nelson. “Through space exploration, advances in aviation, groundbreaking science, new technologies, and more, the team of wizards at NASA do what is hard to achieve what is great. That’s the pioneer spirit that makes NASA the best place to work in the federal government. With this ingenuity and passion, we will continue to innovate for the benefit of all and inspire the world.”

The agency’s workforce explored new frontiers in 2023, including shattering an American record for longest astronaut spaceflight, announcing the Artemis II crew, launching the Deep Space Optical Communications experiment, partnering on a sustainable flight demonstration later designated as X-66, and celebrating a year of science gathered from the agency’s James Webb Space Telescope. Feats beyond our atmosphere persisted with NASA’s OSIRIS-Rex (Origins, Spectral Interpretation, Resource Identification, and Security – Regolith Explorer) mission – the first U.S. mission to collect an asteroid sample. Insights from the asteroid data will further NASA’s studies on celestial objects, while the agency also continues its pursuit to return astronauts to the Moon as part of the Artemis campaign.

Along with being the 65th anniversary of the agency, 2023 brought new climate data with the launching of the U.S. Greenhouse Gas Center and Earth Information Center, new perspectives on Earth’s surface water through NASA’s SWOT (Surface Water and Ocean Topography) mission, and accrued air quality data from NASA’s TEMPO (Tropospheric Emissions: Monitoring of Pollution) mission.

The Partnership for Public Service began to compile the Best Places to Work rankings in 2003 to analyze federal employee’s viewpoints of leadership, work-life balance, and other factors of their job. A formula is used to evaluate employee responses to a federal survey, dividing submissions into four groups: large, midsize, and small agencies, in addition to their subcomponents.

Read about the Best Places to Work for 2023 online.

To learn more about NASA’s missions, visit:

https://www.nasa.gov/

-end-

Faith McKie / Cheryl Warner
Headquarters, Washington
202-358-1600
faith.d.mckie@nasa.gov / cheryl.m.warner@nasa.gov

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Europa has always held a fascination to me. I think it’s the concept of a world with a sub-surface ocean and the possibility of life that has inspired me and many others. In September 2022, NASAs Juno spacecraft made a flyby, coming within 355 kilometres of the surface. Since the encounter, scientists have been exploring the images and have identified regions where brine may have bubbled to the surface. Other images revealed possible, previously unidentified steep-walled depressions up to 50km wide, this could be caused by a free-floating ocean! 

Juno was launched to Jupiter on 5 August 2011. It took off from the Cape Canaveral site on board an Atlas V rocket and travelled around 3 billion kilometres. It arrived at Jupiter on 4 July 2016 and in September 2022 made its closest flyby of Europa. The frozen world is the second of the four Galilean satellites that were discovered by Galileo over 400 years ago. Visible in small telescopes, the true nature of the moon is only detectable by visiting craft like Juno. 

Artist’s impression of NASA’s Galileo space probe in orbit of Jupiter. Credit: NASA

During its close fly-by, one of the onboard cameras known as Juno-Cam took the highest resolution images of the moon since Galileo took a flyby in 2000. The images supported the long held theory that the icy crusts at the north and south poles are not where they used to be. Another instrument on board, known as the Stellar Reference Unit (SRU), revealed possible activity resembling plumes where brine may have bubbled to the surface. 

The ground track over Europa that was followed by Juno enabled imaging around the equatorial regions. The images revealed the usual, expected blocks of ice, walls, ridges and scarps but also found something else. Steep walled depressions that measured 20 to 50 kilometres across were also seen and they resembled large ovoid pits. 

One of Juno’s enormous solar panels, unfurled on Earth. NASA/JPL. SWrI

The observations of the meanderings of the north/south polar ice and the varied surface features all point towards an outer icy shell that is free-floating upon the sub surface ocean.  This can only happen if the outer shell is not connected to the rocky interior. When this happens, there are high levels of stress on the ice which then causes the fracture pattern witnessed. The images represent the first time such patterns have been seen in the southern hemisphere, the first evidence of true polar wandering. 

The images from the SRU surprisingly provided the best quality images. It was originally designed to detect faint light from stars for navigation. Instead, the team used it to capture images when Europa was illuminated by the gentle glow of sunlight reflected from Jupiter. It was quite a novel approach and allowed complex features to become far more pronounced than before. Intricate networks of ridges criss-crossing the surface were identified along with dark stains from water plumes. One feature in particular stood out, nicknamed ‘the Platypus’, it was a 37 kilometre by 67 kilometre region shaped somewhat like a platypus. 

Source : NASA’s Juno Provides High-Definition Views of Europa’s Icy Shell

The post Juno Reveals Secrets About Europa’s Icy Surface appeared first on Universe Today.

Blue Origin plans to launch six people — including the United States' first-ever black astronaut candidate — on a suborbital spaceflight this weekend.

Some AI firms think nuclear power can help meet the electricity demand from Silicon Valley’s data centres, but building new nuclear power stations takes too long to plug the gap in the short term

Some AI firms think nuclear power can help meet the electricity demand from Silicon Valley’s data centres, but building new nuclear power stations takes too long to plug the gap in the short term

SpaceX stacked its giant Starship rocket ahead of the vehicle's fourth test flight, which could launch just a few weeks from now.

Lithuania signed the Artemis Accords on Wednesday (May 15), bringing the number of nations in the moon-exploration pact to 40.

In season 1 premiere 'Space Babies', the Doctor tells Ruby and the cosmic infants that he's the last of the Time Lords. Here's what that means.