Tag Archives: Physical sciences

New Map Shows All the Matter in the Universe

Researchers used data from the Dark Energy Survey and the South Pole Telescope to re-calculate the total amount and distribution of matter in the universe. They found that there’s about six times as much dark matter in the universe as there is regular matter, a finding consistent with previous measurements.

But the team also found that the matter was less clumped together than previously thought, a finding detailed in a set of three papers, all published this week in Physical Review D.

The Dark Energy Survey observes photons of light at visible wavelengths; the South Pole Telescope looks at light at microwave wavelengths. That means the South Pole Telescope observes the cosmic microwave background—the oldest radiation we can see, which dates back to about 300,000 years after the Big Bang.

The team presented the datasets from the respective surveys in two maps of the sky; they then overlaid the two maps to understand the full picture of how matter is distributed in the universe.

“It seems like there are slightly less fluctuations in the current universe than we would predict, assuming our standard cosmological model anchored to the early universe,” said Eric Baxter, an astronomer at the University of Hawai’i and a co-author of the research, in a university release. “The high precision and robustness to sources of bias of the new results present a particularly compelling case that we may be starting to uncover holes in our standard cosmological model.”

Dark matter is something in the universe that we cannot observe directly. We know it’s there because of its gravitational effects, but otherwise we can’t see it. Dark matter makes up about 27% of the universe, according to CERN. (Ordinary matter is about 5% of the universe’s total content.) The remaining 68% is made up of dark energy, a hitherto uncertain category that is evenly distributed throughout the universe and responsible for the universe’s accelerating expansion.

The Dark Energy Survey still has three years of data to be analyzed, and a new look at the cosmic microwave background is currently being undertaken by the South Pole Telescope. Meanwhile, the Atacama Cosmology Telescope (high in the Chilean desert of the same name) is currently taking a high-sensitivity survey of the background. With newly precise data to probe, researchers may be able to put the standard cosmological model to a difficult test.

In 2021, the Atacama telescope helped scientists come up with a newly precise measurement for the age of the universe: 13.77 billion years. More querying of the cosmic microwave background could also help researchers deal with the Hubble tension, a disagreement between two of the best ways for measuring the expansion of the universe. (Depending on how it’s measured, researchers land on two different figures for the rate of that expansion.)

As means of observation get more precise, and more data is collected and analyzed, that information can be fed back into grand cosmological models to determine where we’ve been wrong in the past and lead us to new lines of investigation.

More: Antimatter Could Travel Through Our Galaxy With Ease, Physicists Say

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Astronomers Find Rare Star System That Will Trigger a Kilonova

An artist’s rendition of the binary stay system, called CPD-29 2176.
Illustration: Noir Lab

The universe has no shortage of oddities, and researchers at the National Science Foundation’s NOIRLab have observed another one in the form of a particular binary star system. The system, called CPD-29 2176, will eventually trigger a kilonova, a celestial event in which two neutron stars collide in a massive explosion that forms heavy elements, including gold and platinum.

CPD-29 2176 is located around 11,400 light-years from Earth and was found by researchers using NASA’s Neil Gehrels Swift Observatory. Astronomers then conducted more observations at NOIRLab’s Cerro Tololo Inter-American Observatory in Chile. CPD-29 2176 is home to one neutron star and one massive star that is in the process of going supernova, only to become a second neutron star in the future. Eventually, the two neutron stars will collide, producing a kilonova, an explosion that is thought to produce bursts of gamma rays and large amounts of gold and platinum. The paper documenting the research team’s find is published today in Nature.

“We know that the Milky Way contains at least 100 billion stars and likely hundreds of billions more. This remarkable binary system is essentially a one-in-ten-billion system,” said André-Nicolas Chené in a NOIRLab press release. Chené is a NOIRLab astronomer and an author on the study. “Prior to our study, the estimate was that only one or two such systems should exist in a spiral galaxy like the Milky Way.”

While many stars implode was a powerful supernova when they die, the dying star in CPD-29 2176 is becoming an ultra-stripped supernova. An ultra-stripped supernova lacks the vast amount of force that a typical supernova has, since the dying star has had much of its mass stripped by its companion. The researchers think that the neutron star in the system was also formed with an ultra-stripped supernova and argue that this is the reason that CPD-29 2176 is able to remain as a binary—a typical supernova would have enough power to kick a companion star out of its orbit.

“The current neutron star would have to form without ejecting its companion from the system. An ultra-stripped supernova is the best explanation for why these companion stars are in such a tight orbit,” said lead author Noel D. Richardson, a physics and astronomy professor at Embry-Riddle Aeronautical University, in the NOIRLab release. “To one day create a kilonova, the other star would also need to explode as an ultra-stripped supernova so the two neutron stars could eventually collide and merge.”

It will take around one million years for the star undergoing ultra-stripped supernova to turn into a neutron star. It is then when the two stars will begin to spiral into each other, eventually resulting in the metal-producing kilonova, according to the research. In these dramatic cosmic endings, we can look forward to the creation of the same elements that make life possible.  

More: Watch Four Planets Spin Around a Star 130 Million Light-Years Away

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Webb Telescope Captures Countless Galaxies in New Image

The European Space Agency has released its image of the month for January, and it is (perhaps unsurprisingly) a stunning shot from the Webb Space Telescope.

At the bottom of the image is LEDA 2046648, a spiral galaxy over one billion light-years from Earth in the constellation Hercules. Behind LEDA is a field of more distant galaxies, ranging from spiral shapes to pinpricks of light in the distant universe.

Webb launched from French Guiana in December 2021; its scientific observations of the cosmos began in July. Webb has imaged distant galaxies, exoplanets, and even shed new light on worlds in our local solar system.

Though this image was only just released, it was taken during the commissioning process for one of Webb’s instruments, the Near-Infrared Imager and Slitless Spectrograph (NIRISS), according to an ESA release. While NIRISS was focused on a white dwarf—the core remnant of a star—Webb’s Near-Infrared Camera (NIRCam) turned its focus to LEDA 2046648 and its environs in the night sky.

One of Webb’s primary objectives in looking at the distant universe is to better understand how the first stars and galaxies formed. To that end, the telescope is looking at some of the most ancient light in the universe, primarily through its instruments NIRCam and MIRI.

The image does contains hundreds of light sources our eye can perceive, but the infrared data from which the image was formed certainly records many more galaxies.

Webb’s deep field imagery is what enables scientists to see some of the most ancient light in the universe, often capitalizing on gravitational lensing (the magnification of distant light due to the gravitational warping of spacetime) to see particularly ancient sources.

Though this shot of LEDA 2046648 is not a deep field, it evokes a similar feeling: awe, at the huge scale of the cosmos, and (if only briefly) the realization that our minds can only comprehend a fraction of it.

More: Zoom in on Webb Telescope’s Biggest Image Yet

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Meteorite Hunters Find 17-Pound Space Rock in Antarctica

The 16.7 pound (7.6 kilogram) meteorite was found sitting on the surface of the Antarctic desert, where its black composition contrasted against the snow.
Image: Maria Valdes

Researchers combing the surface of Antarctica for space rocks hit the jackpot by finding five meteorites in the tundra, one of which weighs almost 17 pounds.

The expedition team found the meteorites sitting on top of the snow in Antarctica, where the rocks’ black bodies stuck out against the white snow fields of the continent. Antarctica is an ideal place to find relatively undisturbed space rocks, since its dry climate prevents excess weathering over time. Maria Valdes, a research scientist with the Field Museum and the University of Chicago, and her team found a total of five meteorites during their hunt in December, one of which weighs 16.7 pounds (7.6 kilograms).

“Size doesn’t necessarily matter when it comes to meteorites, and even tiny micrometeorites can be incredibly scientifically valuable,” said Valdes in a statement. “But of course, finding a big meteorite like this one is rare, and really exciting.”

Researchers Maria Schönbächler, Maria Valdes, Ryoga Maeda, and Vinciane Debaille pose with the largest of the meteorites.
Image: Maria Valdes

Valdes estimates that, out of the tens of thousands of meteorites that have been found in Antarctica, only around 100 are as large as the one her team found. To find the meteorites, the researchers rode on snow mobiles and walked in areas that were previously mapped and identified through satellite imagery as potential landing spots for meteorites. When the team found a suspected meteorite, they used a handheld tool to test the magnetic properties of the rock, Valdes explained in an email to Gizmodo. While most of these meteorites stay on the surface, even those that sink into the ice will reemerge as glaciers shift and move.

“Going on an adventure exploring unknown areas is exciting,” said Vinciane Debaille, a member of the research team from Université Libre de Bruxelles, in a statement. “But we also had to deal with the fact that the reality on the ground is much more difficult than the beauty of satellite images.”

While the find is exciting, the next step for the scientists is to determine what the meteorites can tell us about the universe. The five rocks Valdes and her team found with be analyzed at the Royal Belgian Institute of Natural Sciences, while soil samples from the area will be analyzed by the team themselves.

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NASA Reveals Details About Habitable Worlds Observatory

An artist’s concept of LUVOIR, a 15-meter telescope that was an early NASA concept for a future space telescope. The newly described Habitable Worlds Telescope wouldn’t be quite as large as this.

NASA officials disclosed information about a planned next-generation space telescope, the Habitable Worlds Observatory, during a recent session of the American Astronomical Society,

In the session, Mark Clampin, the Astrophysics Division Director NASA’s Science Mission Directorate, offered a few details about the telescope, which could be operational in the early 2040s.

The need for such an observatory is outlined in the National Academies of Sciences, Engineering, and Medicine’s decadal survey on astronomy and astrophysics, a report assembled by hundreds of industry experts that serves as a reference document for the fields’ future goals.

One of the key findings of the most recent decadal survey was the necessity of finding habitable worlds beyond our own, using a telescope tailored specifically for such a purpose. The report suggested an $11 billion observatory—one with a 6-meter telescope that would take in light at optical, ultraviolet, and near-infrared wavelengths. (Hubble Space Telescope sees mostly in optical and ultraviolet light, while the more recently launched Webb Space Telescope images at mid-infrared and near-infrared wavelengths.)

The authors of the decadal survey suggested the Habitable Worlds Observatory as the first in a new Great Observatories program; basically, the linchpin in the next generation of 21st-century space telescopes. As Science reported, the decadal report’s suggestion of an exoplanet-focused space telescope falls somewhere between two older NASA proposals, telescope concepts named HabEx and LUVOIR.

Exoplanets are found with regularity; it’s finding worlds with conditions that can host life as we know it that’s tricky. Webb has spotted exoplanets and deduced aspects of their atmospheric chemistry, and other telescopes (even planned ones, like the Roman Space Telescope) are turning their gaze toward these alien worlds.

Unlike other telescopes—both operational and those still on the drawing board—the planned Habitable Worlds Observatory would look specifically for so-called Goldilocks planets, worlds with conditions that could foster life.

The search for extraterrestrial life is a relentless goal of NASA. The Perseverance rover on Mars is collecting rock samples on Mars to learn, among other things, whether there’s any evidence for ancient microbial life in a region of the planet that once was a flowing river delta. (An environment, it’s important to note, that scientists believe was similar to that where Earth’s first known life materialized.)

Beyond Mars, scientists harbor hope that future probes can poke around for signs of life in the subsurface ocean on Jupiter’s moon Europa or the methane sea on Saturn’s moon Titan.

But those are just venues—and hostile ones, compared to Earth—within our solar system. Missions like TESS and the Kepler Space Telescope have detected thousands of exoplanets, but the fraction that are Earth-like is vanishingly small.

Like the Webb telescope, the future observatory will be located at L2, a region of space one million miles from Earth that allows objects to remain in position with relatively little fuel burn. (By saving fuel, the missions’ lifespans are prolonged.)

As reported by Science, Clampin said that the Habitable Worlds Observatory would be designed for maintenance and upgrades, which Webb is not. That could make the next observatory a more permanent presence in NASA’s menagerie of space telescopes.

Hubble was famously serviced by humans in low-Earth orbit multiple times, due to a number of mechanical snafus and issues that have arisen over the telescope’s 32-year tenure in space.

The Habitable Worlds Observatory repairs and upgrades (which would take place a million miles from Earth—a little far for human repairs) would be done robotically, more in the style of a Star Wars droid than a hand from the IT department.

Space News reported that NASA will imminently begin seeking out nominations for people to join the Science, Technology, Architecture Review Team (START) for the new observatory. The first phase of the observatory’s development is slated for 2029.

In November, Clampin told a House subcommittee that the Webb telescope had suffered 14 strikes from micrometeoroids—very small bits of fast-traveling space rock that can damage the telescope’s mirrors. Clampin said the NASA team was “making some operational changes to make sure we avoid any future impacts,” and the telescope was slightly repositioned to reduce the risk of future strikes.

One of the telescope’s mirror segments was damaged by a micrometeoroid strike, but an analysis by the team found the telescope “should meet its optical performance requirements for many years.”

Of paramount importance to the astronomical community is that the budget and timeline of the new observatory stay on track. The Webb project was years late and way over budget. Space News reports that some scientists are calling for an expedited timeline that could see the Habitable Worlds Observatory launch by 2035.

The ball is well and truly rolling on the telescopes of the future. The question is how Sisyphean the roll of the ball will be.

More: Webb Telescope Spots Ancient Galaxy Built Like the Milky Way

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Astronomers Find the Edge of Our Galaxy

The Andromeda Galaxy captured by the NASA Galaxy Evolution Mapper in 2012.
Image: NASA/JPL-Caltech

In the quest to find the outer limits of our galaxy, astronomers have discovered over 200 stars that form the Milky Way’s edge, the most distant of which is over one million light-years away—nearly halfway to the Andromeda galaxy.

The 208 stars the researchers identified are known as RR Lyrae stars, which are stars with a brightness that can change as viewed from Earth. These stars are typically old and brighten and dim at regular intervals, which is a mechanism that allows scientists to calculate how far away they are. By calculating the distance to these RR Lyrae stars, the team found that the farthest of the bunch was located about halfway between the Milky Way and the Andromeda galaxy, one of our cosmic next-door neighbors.

“This study is redefining what constitutes the outer limits of our galaxy,” said Raja GuhaThakurta in a press release. GuhaThakurta is professor and chair of astronomy and astrophysics at the University of California Santa Cruz. “Our galaxy and Andromeda are both so big, there’s hardly any space between the two galaxies.”

Illustration: NASA, ESA, AND A. FEILD (STSCI)

The Milky Way galaxy consists of a few different parts, the primary of which is a thin, spiral disk about 100,000 light-years across. Our home solar system sits on one of the arms of this disk. An inner and outer halo surround the disk, and these halos contain some of the oldest stars in our galaxy.

Previous studies have placed the edge of the outer halo at 1 million light-years from the Milky Way’s center, but based on the new work, the edge of this halo should be about 1.04 million light-years from the galactic center. Yuting Feng, a doctoral student at the university working with GuhaThakurta, led the study and is presenting the findings this week at the American Astronomical Society meeting in Seattle.

“We were able to use these variable stars as reliable tracers to pin down the distances,” said Yuting Feng, a doctoral student at the university working with GuhaThakurta. “Our observations confirm the theoretical estimates of the size of the halo, so that’s an important result.”

Space is vast and lonely—but we can feel a bit cozier knowing that our galactic neighbor is closer than we thought.

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Webb Telescope Spots Ancient Galaxy Built Like the Milky Way

The Webb Space Telescope’s latest target is one previously imaged by Hubble: the distant barred spiral galaxy EGS23205. Targets like this one will boost our understanding of the early universe and how ancient stars and galaxies took form.

The two images above show EGS23205 as seen by Hubble and Webb. Hubble’s image of the galaxy (taken in near-infrared) is much noisier, and the structure of the galaxy is harder to discern. But Webb’s image (at mid-infrared wavelengths) is much crisper, revealing a clear bar of stars stretching out from the galactic center.

Stellar bars are huge galactic cross-sections composed of countless stars. The bars play an important role in galactic evolution; they push gas toward the galactic center, helping fuel star formation and feed the supermassive black holes that lie within galactic nuclei. Our own Milky Way is a barred spiral galaxy.

Analysis of the image was submitted to the preprint server arXiv last year. Webb has imaged many ancient galaxies in its mere six months of scientific operations.

Some of Webb’s targets are among the earliest galaxies yet seen, and they appear to Webb as they were just several hundred million years after the Big Bang (the universe is now close to 14 billion years old).

Webb telescope reveals Milky Way–like galaxies in young universe

EGS23205 is seen as it was about 11 billion years ago. The image reveals that even early galaxies had well-defined bars (spiral galaxies were previously thought to be much later arrivals in the universe).

“The bars hardly visible in Hubble data just popped out in the JWST image, showing the tremendous power of JWST to see the underlying structure in galaxies,” said Shardha Jogee, an astronomer at UT Austin and co-author of the research, in a press release.

Webb has previously imaged other objects once captured by Hubble. In October, the new $10 billion observatory beheld the Pillars of Creation, huge plumes of gas and dust in the Eagle Nebula. In the same month, the Webb team produced an image of merging galaxies 270 million light-years from Earth, imaged by Hubble back in 2008.

The two space telescopes observe at different wavelengths for the most part—Hubble primarily at visible wavelengths and Webb primarily in the infrared and near-infrared. Webb’s vivid handiwork is built on the mechanical shoulders of Hubble. Side-by-side image comparisons show the differences in these impressive observatories, and what’s possible with the newest technology.

More: The Year Ahead in Astronomy

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An Asteroid Is Passing Earth Today, so Scientists Are Shooting It With Radio Waves

The HAARP facility’s antenna array includes 180 antennas spread across 33 acres.
Photo: HAARP

A group of researchers is attempting to bounce radio signals off a 500-foot-wide asteroid during its close flyby of Earth on Tuesday.

The High Frequency Active Auroral Research Program (HAARP) is aiming its antennas at asteroid 2010 XC15, a space rock that’s categorized as a near-Earth potentially hazardous asteroid. The effort is a test run to to prepare for a larger object, known as Apophis, that will have a close encounter with our planet in 2029.

“What’s new and what we are trying to do is probe asteroid interiors with long wavelength radars and radio telescopes from the ground,” Mark Haynes, lead investigator on the project and a radar systems engineer at NASA’s Jet Propulsion Laboratory in Southern California, said in a statement. “Longer wavelengths can penetrate the interior of an object much better than the radio wavelengths used for communication.”

HAARP is a research facility in Gakona, Alaska (one that’s been the subject of plenty of conspiracy theories). It’s made up of 180 high-frequency antennas, each standing at 72 feet tall and stretched across 33 acres. The facility transmits radio beams toward the ionosphere, the ionized part of the atmosphere that’s located about 50 to 400 miles (80 to 600 kilometers) above Earth’s surface. HAARP sends radio signals to the ionosphere and waits to see how they return, in an effort to measure the disturbances caused by the Sun, among other things.

The facility launched a science campaign in October with 13 experiments, including one that involved bouncing signals off the Moon. At the time, HAARP researchers were considering sending a radio signal to an asteroid to investigate the interior of the rocky body.

During today’s experiment, the HAARP antennas in Alaska will transmit the radio signals to the asteroid, and then scientists will check if the reflected signals arrive at antenna arrays at the University of New Mexico Long Wavelength Array and California’s Owens Valley Radio Observatory Long Wavelength Array.

HAARP will transmit a continually chirping signal at slightly above and below 9.6 megahertz; the chirp will repeat at two-second intervals. At its closest approach on December 27, the asteroid will be twice as far as the Moon is from Earth.

Tuesday’s experiment is to prepare for an upcoming encounter with an asteroid in 2029. That potentially hazardous asteroid, formally known as 99942 Apophis, is around 1,210 feet (370 meters) wide, and it will come to within 20,000 miles (32,000 kilometers) of Earth on April 13, 2029. The near-Earth object was thought to pose a slight risk to Earth in 2068, but NASA ruled that out.

Still, HAARP wants to probe the asteroid to prepare for potential risks in the future from space rocks. “The more time there is before a potential impact, the more options there are to try to deflect it,” Haynes said.

In September, NASA’s DART spacecraft smacked into a small asteroid and successfully altered its orbit. Such a strategy could be one way to divert a space rock that threatens Earth.

Today’s test shows the potential of using long wavelength radio signals to probe the interiors of asteroids. “If we can get the ground-based systems up and running, then that will give us a lot of chances to try to do interior sensing of these objects,” Haynes said.

More: A Powerful Recoil Effect Magnified NASA’s Asteroid Deflection Experiment

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This Asteroid Impact Simulator Lets You Destroy the World

I aimed a 1,500-foot iron asteroid traveling at 38,000 miles per hour with a 45-degree impact angle at Gizmodo’s office in Midtown, Manhattan.
Screenshot: Gizmodo/Neal.Fun

Hundreds of thousands of asteroids lurk in our solar system, and while space agencies track many of them, there’s always the chance that one will suddenly appear on a collision course with Earth. A new app on the website Neal.fun demonstrates what could happen if one smacked into any part of the planet.

Neal Agarwal developed Asteroid Simulator to show the potentially extreme local effects of different kinds of asteroids. The first step is to pick your asteroid, with choices of iron, stone, carbon, and gold, or even an icy comet. The asteroid’s diameter can be set up to 1 mile (1.6 kilometers); its speed can be anywhere from 1,000 to 250,000 miles per hour; and the impact angle can be set up to 90 degrees. Once you select a strike location on a global map, prepare for chaos.

“I grew up watching disaster movies like Deep Impact and Armageddon, and so I always wanted to make a tool that would let me visualize my own asteroid impact scenarios,” Agarwal said to Gizmodo in an email. “I think this tool is for anyone who loves playing out ‘what-if’ scenarios in their head. The math and physics behind the simulation is based on research papers by Dr. Gareth Collins and Dr. Clemens Rumpf who both study asteroid impacts.”

Once you’ve programmed the asteroid and launched it at your desired target, Asteroid Simulator will walk you through the devastation. First, it’ll show you the width and depth of the crater, the number of people vaporized by the impact, and how much energy was released. It will then walk you through the size and effects of the fireball, shock wave, wind speed, and earthquake generated by the asteroid.

NASA has its eyes on more than 19,000 near-Earth asteroids. While no known space rock poses an imminent threat to Earth, events like the 2013 Chelyabinsk impact in Russia remind us of the need for robust planetary defense. Just this year, NASA tested an asteroid deflection strategy via its DART spacecraft, to resounding success.

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A Software Glitch Forced the Webb Space Telescope Into Safe Mode

The Webb Space Telescope’s instruments have been in safe mode intermittently since December 7, but scientific operations resumed earlier this week, NASA said in a press release on Wednesday.

Webb was in safe mode—during which all the observatory’s nonessential systems are turned off, which means no scientific operations—multiple times in the last two weeks, the release stated. Though NASA says the issue is resolved and “the observatory and instruments are all in good health,” the agency also did not report the glitch until yesterday.

Webb is a $10 billion space observatory that images the cosmos at infrared and near-infrared wavelengths. It is a state-of-the-art telescope that has captured our attention in its first six months of scientific observations, revealing iconic structures like the Pillars of Creation in new light.

The NASA release says the “software fault triggered in the attitude control system,” the apparatus that guides where the observatory is pointing. That’s most directions, except that the telescope was turned away from the micrometeoroid avoidance zone in the spring, to protect the telescope’s mirrors. That maneuver came following a space rock strike that damaged one of the mirror panels.

The pauses added up to several days that the telescope could not do observations this month, NASA said. Now, science is fully back underway, and the Webb team is working to reschedule the observations affected by the glitch.

Yesterday, Webb posted the cosmic equivalent of a holiday card: an image of the spiral galaxy NGC 7469, which bears a resemblance to a wreath. The galaxy is 220 million light-years away and looks distinctly serene in Webb’s eye. Sharp diffraction spikes spread from the galactic center, where a supermassive black hole resides.

Besides seeing known objects in new ways, Webb has imaged light from the earliest corners of the universe, light which was too faint for older observatories to see.

One of Webb’s core scientific goals is to inspect ancient light sources—the earliest stars and galaxies—to understand how those objects emerged and evolved in deep time.

In other words, it’d be really nice if Webb could avoid safe mode, for the sake of science. But better safe than sorry, and now that the telescope is back to business, let’s hope it stays that way.

More: Webb Telescope Brings a Once-Fuzzy Galaxy Into Focus

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