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Entangled by gravity and destined to merge, two candidate black holes in a distant galaxy appear to be locked in an intricate dance. Researchers using data from NASA’s Galaxy Evolution Explorer (GALEX) and NASA’s Hubble Space Telescope have come up with the most compelling confirmation yet for the existence of these merging black holes and have found new details about their odd, cyclical light signal. The candidate black hole duo, called PG 1302-102, was first identified earlier this year using ground-based telescopes....

A little-known ocean-dwelling creature most commonly found growing on dead hermit crab shells may sound like an unlikely study subject for researchers, but this animal has a rare ability ­– it can make eggs and sperm for the duration of its lifetime. This animal, called Hydractinia, does so because it produces germ cells, which are precursors to eggs and sperm, nonstop throughout its life. Studying this unique ability could provide insight into the development of human reproductive system and the formation of reproductive-based conditions and diseases in humans....

While satellites have confirmed that Greenland has lost a significant part of its ice sheet, a recent study in Science indicates that the ice sheet may be able to slow its melting much quicker than previously thought. Kurt Kjær of the University of Copenhagen and his Danish colleagues have used aerial photos of the ice sheet, dating back to the early ’80s, to compare episodes of rapid melting in the last few decades....

The image was taken at 23:44:12 UTC by the Mercury Transfer Module’s Monitoring Camera 2, when the spacecraft was about 2418 km from Mercury. Closest approach of about 199 km took place shortly before, at 23:34 UTC. In this view, north is towards the lower right. The cameras provide black-and-white snapshots in 1024 x 1024 pixel resolution. The region shown is part of Mercury’s northern hemisphere including Sihtu Planitia that has been flooded by lavas....

The Herschel observatory, a European space telescope for which NASA helped build instruments and process data, has stopped making observations after running out of liquid coolant as expected. The European Space Agency mission, launched almost four years ago, revealed the universe’s “coolest” secrets by observing the frigid side of planet, star and galaxy formation. “Herschel gave us the opportunity to peer into the dark and cold regions of the universe that are invisible to other telescopes,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate at NASA headquarters in Washington....

The optics engineering expertise at the NASA’s Marshall Space Flight Center in Huntsville, Alabama, made it possible for a group of solar scientist to see into the sun’s corona in unprecedented detail. The final mirror configuration was completed with inputs from partners at the Smithsonian Astrophysical Observatory, or SAO, in Cambridge, Massachusetts, and a new manufacturing technique developed in coordination with L-3Com/Tinsley Laboratories of Richmond, California. The High Resolution Coronal Imager, or Hi-C, captured the highest-resolution images ever taken of the million-degree solar corona using a resolution five times higher than previous imagers....

The findings, published today in the journal Nature Materials, show that corrosion of nuclear waste storage materials accelerates because of changes in the chemistry of the nuclear waste solution, and because of the way the materials interact with one another. “This indicates that the current models may not be sufficient to keep this waste safely stored,” said Xiaolei Guo, lead author of the study and deputy director of Ohio State’s Center for Performance and Design of Nuclear Waste Forms and Containers, part of the university’s College of Engineering....

If we go far enough back in evolutionary history, we encounter the last known common ancestor of humans and cephalopods: a primitive wormlike animal with minimal intelligence and simple eyespots. Later, the animal kingdom can be divided into two groups of organisms – those with backbones and those without. While vertebrates, particularly primates and other mammals, went on to develop large and complex brains with diverse cognitive abilities, invertebrates did not....

A highly virulent variant of HIV-1 has been circulating in the Netherlands for the past few decades, researchers report. According to the new study, a cluster of more than 100 individuals infected with the subtype showed exceptionally high viral loads, rapid CD4 T cell decline, and increased infectivity. While the findings show that the HIV lineage likely arose de novo around the turn of the millennium, extensive changes in its genome make it hard to discern the mechanisms that underlie its elevated virulence....

Before examinations and in critical situations, we need to be particularly receptive and capable of learning. However, acute exam stress and stage fright causes learning blockades and reduced memory function. Scientists from the Max Planck Institute of Psychiatry in Munich have now discovered a mechanism responsible for these cognitive deficits, which functions independently of stress hormones. In animal studies, the researchers show that social stress reduces the volume of Homer-1 in the hippocampus – a region of the brain that plays a central role in learning....

The study focused on one scroll, in particular, known as the Temple Scroll, among the roughly 900 full or partial scrolls found in the years since that first discovery. The scrolls were found in jars hidden in 11 caves on the steep hillsides just north of the Dead Sea, in the region around the ancient settlement of Qumran, which was destroyed by the Romans about 2,000 years ago. It is thought that to protect their religious and cultural heritage from the invaders, members of a sect called the Essenes hid their precious documents in the caves, often buried under a few feet of debris and bat guano to help foil looters....

Dietary fats are converted into lipids, which make up the membranes that surround all living cells. The type of fat a person consumes may determine whether stem cells are converted into bone cells or fat cells, said Ilya Levental, Ph.D., the study’s senior author and assistant professor of integrative biology and pharmacology at McGovern Medical School at UTHealth. “The fats that we consume such as cholesterol, unsaturated fats, and fish oil become robustly incorporated into the membranes of our cells and dramatically change the composition and function of those membranes,” said Levental, a Cancer Prevention & Research Institute of Texas (CPRIT) Scholar....

For a long time, anecdotes have connected stressful experiences with the phenomenon of hair graying. Now, for the first time, HSCI scientists have discovered exactly how the process plays out: stress activates nerves that are part of the fight-or-flight response, which in turn cause permanent damage to pigment-regenerating stem cells in hair follicles. The study, published in Nature on January 22, 2020, advances scientists’ knowledge of how stress can impact the body....

The publicly available dataset resulting from approximately a thousand new experiments represents the most detailed map of connections in a mammalian brain to date, tracing neural wiring within and between the thalamus and cortex, the outermost shell of the mammalian brain that is responsible for higher level functions like memory, decision making, and understanding the world around us. Sifting through the data, the researchers uncovered an underlying “org chart” of wiring among the different areas comprising these two structures, showing a defined order to the connections that are the underpinnings of what makes our brains tick....

Great balls of fire! NASA’s Hubble Space Telescope has detected superhot blobs of gas, each twice as massive as the planet Mars, being ejected near a dying star. The plasma balls are zooming so fast through space it would take only 30 minutes for them to travel from Earth to the moon. This stellar “cannon fire” has continued once every 8.5 years for at least the past 400 years, astronomers estimate....

This colorful bubble is a planetary nebula called NGC 6818, also known as the Little Gem Nebula. It is located in the constellation of Sagittarius (The Archer), roughly 6,000 light-years away from us. The rich glow of the cloud is just over half a light-year across — humongous compared to its tiny central star — but still a little gem on a cosmic scale. When stars like the sun enter “retirement,” they shed their outer layers into space to create glowing clouds of gas called planetary nebulae....

Often referred to by its somewhat drier New General Catalogue designation of NGC 4194, this was not always one entity, but two. An early galaxy consumed a smaller gas-rich system, throwing out streams of stars and dust into space. These streams, seen rising from the top of the merged galaxy, resemble the writhing snakes that Medusa, a monster in ancient Greek mythology, famously had on her head in place of hair, lending the object its intriguing name....

At the center of this blue cloud lies what remains of the nebula’s progenitor star. This cool, dim, and extremely dense star is actually a pulsating white dwarf, meaning that its brightness varies over time as gravity causes waves that pulse throughout the small star’s body. NGC 2452 was discovered by Sir John Herschel in 1847. He initially defined it as “an object whose nature I cannot make out. It is certainly not a star, nor a close double star […] I should call it an oblong planetary nebula....

Using the sharp-eyed NASA Hubble Space Telescope, astronomers have for the first time precisely measured the rotation rate of a galaxy based on the clock-like movement of its stars. According to their analysis, the central part of the neighboring galaxy, called the Large Magellanic Cloud (LMC), completes a rotation every 250 million years. Coincidentally, it takes our Sun the same amount of time to complete a rotation around the center of our Milky Way galaxy....

Huge waves are sculpted in this two-lobed nebula called the Red Spider Nebula. This warm planetary nebula harbors one of the hottest stars known and its powerful stellar winds generate waves 100 billion kilometers (62.4 billion miles) high. The waves are caused by supersonic shocks, formed when the local gas is compressed and heated in front of the rapidly expanding lobes. The atoms caught in the shock emit the spectacular radiation seen in this image....