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Explanation: Despite their resemblance to R2D2, these three are not the droids you're looking for. Instead, the enclosures house 1.8 meter Auxiliary Telescopes (ATs) at Paranal Observatory in the Atacama Desert region of Chile. The ATs are designed to be used for interferometry, a technique for achieving extremely high resolution observations, in concert with the observatory's 8 meter Very Large Telescope units. A total of four ATs are operational, each fitted with a transporter that moves the telescope along a track allowing different arrays with the large unit telescopes. To work as an interferometer, the light from each telescope is...

Explanation: A mere 280 light-years from Earth, tidally locked, Jupiter-sized exoplanet WASP-43b orbits its parent star once every 0.8 Earth days. That puts it about 2 million kilometers (less than 1/25th the orbital distance of Mercury) from a small, cool sun. Still, on a dayside always facing its parent star, temperatures approach a torrid 2,500 degrees F as measured at infrared wavelengths by the MIRI instrument on board the James Webb Space Telescope. In this illustration of the hot exoplanet's orbit, Webb measurements also show nightside temperatures remain above 1,000 degrees F. That suggests that strong equatorial winds circulate the...

Explanation: Majestic on a truly cosmic scale, M100 is appropriately known as a grand design spiral galaxy. The large galaxy of over 100 billion stars has well-defined spiral arms, similar to our own Milky Way. One of the brightest members of the Virgo Cluster of galaxies, M100, also known as NGC 4321 is 56 million light-years distant toward the well-groomed constellation Coma Berenices. In this telescopic image, the face-on grand design spiral shares a nearly 1 degree wide field-of-view with slightly less conspicuous edge-on spiral NGC 4312 (at upper right). The 21 hour long equivalent exposure from a dark sky...

(NASA, ESA, CSA, Ralf Crawford (STScI)) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Scientists using NASA’s James Webb Space Telescope (JWST) have successfully mapped the weather on a planet 280 light years away. Earlier detections made by older space telescopes had hinted at the presence of an atmosphere on WASP-43b, however, the instruments aboard the JWST are the first to measure the actual weather in the planet’s atmosphere. “With Hubble, we could clearly see that there is water vapor on the dayside. Both Hubble and Spitzer suggested there might be clouds on the nightside,” explained Taylor Bell, a researcher from the Bay Area Environmental Research Institute...

Explanation: To some, this nebula looks like the head of a fish. However, this colorful cosmic portrait really features glowing gas and obscuring dust clouds in IC 1795, a star forming region in the northern constellation Cassiopeia. The nebula's colors were created by adopting the Hubble color palette for mapping narrowband emissions from oxygen, hydrogen, and sulfur atoms to blue, green and red colors, and further blending the data with images of the region recorded through broadband filters. Not far on the sky from the famous Double Star Cluster in Perseus, IC 1795 is itself located next to IC 1805,...

The solar flare is the most powerful eruption from sunspot region R3654 yet. Last night (April 30), the sun released an extremely powerful solar flare triggering widespread radio blackouts across the Pacific region. The flare peaked at 7:46 p.m. EDT (2346 GMT) and ended shortly after at 7:58 p.m. EDT (2358). Solar flares are eruptions from the sun's surface that emit intense bursts of electromagnetic radiation. They are created when magnetic energy builds up in the solar atmosphere and is released. Solar flares are categorized by size into lettered groups, with X-class being the most powerful. Then there are M-class...

Explanation: The star system GK Per is known to be associated with only two of the three nebulas pictured. At 1500 light years distant, Nova Persei 1901 (GK Persei) was the second closest nova yet recorded. At the very center is a white dwarf star, the surviving core of a former Sun-like star. It is surrounded by the circular Firework nebula, gas that was ejected by a thermonuclear explosion on the white dwarf's surface -- a nova -- as recorded in 1901. The red glowing gas surrounding the Firework nebula is the atmosphere that used to surround the central star....

Scientists have taken a significant step in understanding these whirling quasiparticles and putting them to work in future semiconductor technologies. Researchers reported that they have imaged the exciton’s electron and hole for the first time, revealing how excitons may be trapped in dense, stable arrays. According to the scientists, the findings have significant implications for the development of various future technologies as well as the quest to better understand excitons. The findings were published on March 8th, 2022, in the journal Nature by researchers from the Department of Energy’s SLAC National Accelerator Laboratory, Stanford University, and the Okinawa Institute for...

In 1957, the astrophysicist Herman Bondi wrote a paper in which he considered the possible existence of a negative mass in Albert Einstein’s theory of gravity. A negative mass would repel a positive mass away from it. Given that, a pair of positive and negative masses could accelerate together up to the speed of light. The negative mass would push away the positive mass which in turn would pull the negative mass for the ride. The runaway pair would accelerate indefinitely, without any need for fuel or a propulsion system. Energy conservation would not be violated because the sum of...

...Unlike most near-Earth asteroids, which are thought to hail from the main asteroid belt between the orbits of Mars and Jupiter, asteroid 2016 HO3, also known as Kamo'oalewa, was likely blasted from the Giordano Bruno crater on the moon's far side and has been hurtling through space for several million years...Measuring between 150 and 190 feet in diameter, the asteroid is about half the size of the "London Eye" Ferris wheel...Previous research pointing to Kamo'oalewa likely originating from the moon included its reflectance spectrum, which is more compatible with lunar materials rather than the general population of near-Earth asteroids, and...

While we don't like to talk ill of the dead, new physiological analysis has found that the king of the dinosaurs was not so smart after all. It upends previous research that last year likened the brain and neuronal composition of the Tyrannosaurus rex to that of a primate. It's been a rough year or two for the long extinct dinosaur. First, we questioned their teeth, finding that those iconic chompers could very much have been smaller and hidden behind lips, and now an international team of paleontologists, behavioral scientists and neurologists have concluded that the T. rex wasn't smarter...

Explanation: Three bright objects satisfied seasoned stargazers of the western sky just after sunset earlier this month. The most familiar was the Moon, seen on the upper left in a crescent phase. The rest of the Moon was faintly visible by sunlight first reflected by the Earth. The bright planet Jupiter, the largest planet in the Solar System, is seen to the upper left. Most unusual was Comet 12P/Pons-Brooks, below the Moon and showing a stubby dust tail on the right but an impressive ion tail extending upwards. The featured image, a composite of several images taken consecutively at the...

Discovering a machine that could somehow produce thrust without releasing propellant would be a game-changer for human space travel. There’s just one problem—such a device would defy the laws of physics.

Explanation: The Ring Nebula (M57) is more complicated than it appears through a small telescope. The easily visible central ring is about one light-year across, but this remarkably deep exposure - a collaborative effort combining data from three different large telescopes - explores the looping filaments of glowing gas extending much farther from the nebula's central star. This composite image includes red light emitted by hydrogen as well as visible and infrared light. The Ring Nebula is an elongated planetary nebula, a type of nebula created when a Sun-like star evolves to throw off its outer atmosphere and become a...

Explanation: If the Sun is up but the sky is dark and the horizon is bright all around, you might be standing in the Moon's shadow during a total eclipse of the Sun. In fact, the all-sky Moon shadow shown in this composited panoramic view was captured from a farm near Shirley, Arkansas, planet Earth. The exposures were made under clear skies during the April 8 total solar eclipse. For that location near the center line of the Moon's shadow track, totality lasted over 4 minutes. Along with the solar corona surrounding the silhouette of the Moon planets and stars...

Explanation: In northern hemisphere spring, bright star Regulus is easy to spot above the eastern horizon. The alpha star of the constellation Leo, Regulus is the spiky star centered in this telescopic field of view. A mere 79 light-years distant, Regulus is a hot, rapidly spinning star that is known to be part of a multiple star system. Not quite lost in the glare, the fuzzy patch just below Regulus is diffuse starlight from small galaxy Leo I. Leo I is a dwarf spheroidal galaxy, a member of the Local Group of galaxies dominated by our Milky Way Galaxy and...

On the cold dead surface of Mars, something remarkable happens each spring. The red planet becomes infested with giant black spiders. At least, that’s what it looks like. In reality, vast fields of dark, spider-like formations become etched into the Red Planet’s landscape. No, they are not alive, nor actually spiders, but instead a geological phenomenon that occurs nowhere else in the solar system. With the recent orbital passes of the European Space Agency’s (ESA) Mars Express and the ExoMars Trace Gas Orbiter (TGO), scientists are now closer than ever to understanding these mysterious features known as “araneiforms.” Araneiforms are...

Explanation: Located some 3 million light-years away in the arms of nearby spiral galaxy M33, giant stellar nursery NGC 604 is about 1,300 light-years across. That's nearly 100 times the size of the Milky Way's Orion Nebula, the closest large star forming region to planet Earth. In fact, among the star forming regions within the Local Group of galaxies, NGC 604 is second in size only to 30 Doradus, also known as the Tarantula Nebula in the Large Magellanic Cloud. Cavernous bubbles and cavities in NGC 604 fill this stunning infrared image from the James Webb Space Telescope's NIRCam. They...

Explanation: How did a star form this beautiful nebula? In the middle of emission nebula NGC 6164 is an unusually massive star. The central star has been compared to an oyster's pearl and an egg protected by the mythical sky dragons of Ara. The star, visible in the center of the featured image and catalogued as HD 148937, is so hot that the ultraviolet light it emits heats up gas that surrounds it. That gas was likely thrown off from the star previously, possibly the result of a gravitational interaction with a looping stellar companion. Expelled material might have been...

In the far reaches of our solar system beyond the orbit of Neptune, a mysterious and yet-unseen world may be lurking in the darkness. Dubbed “Planet 9,” this hypothetical celestial body has been the subject of intense scientific debate and speculation since its existence was first proposed in 2016. Now, a new study published to the arXiv pre-print service by a team from the California Institute of Technology, Université Côte d’Azur, and Southwest Research Institute has provided compelling evidence supporting the presence of this enigmatic planet. The origin of the Planet 9 hypothesis stems from the peculiar alignments in the...