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    How Russia’s war in Ukraine hinders space research and exploration

    Space exploration may seem like a faraway endeavor from Earth’s surface, but events on the ground ripple into space. The Russian war on Ukraine is no exception.

    From a rocket launch system to a rover set to explore Mars, a wide range of space missions is facing postponements or cancelations due to escalating tensions on the ground in the wake of Russia’s full-scale invasion into Ukraine on February 24. The European Union, United States and others have imposed sanctions on Russia; Russia, as a result, is continually changing and canceling its space-related plans. The shifts are having an impact on everything from international collaborations to missions that rely on Russian rockets to get to space.

    Here’s a closer look at some of those projects.

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    ExoMars rover

    The ExoMars mission is a partnership between the European Space Agency and the Russian space agency Roscosmos. This is a two-part mission to Mars consisting of an orbiter and a rover. The orbiter has been at the Red Planet since late 2016, but the Rosalind Franklin rover was supposed to launch this September (SN: 10/18/16).

    “The sanctions and the wider context make a launch in 2022 very unlikely,” the European Space Agency, or ESA, said in a February 28 statement in response to Russia’s invasion of Ukraine.

    Due to Earth’s and Mars’ orbital geometry, the most direct trajectory for a spacecraft from our planet to Mars repeats every two years, and that launch window remains open for less than two weeks. The ExoMars rover, which will look for signs of past life, was originally to launch in 2020, but due to the pandemic and technical issues, it slipped to 2022 (SN: 3/12/20). Now it’s at risk of slipping again to 2024.

    The eROSITA telescope

    Spectrum-Roentgen-Gamma is a space-based X-ray observatory, run jointly by Germany and Russia, that has been mapping the large-scale structure of the universe for the last two and a half years (SN: 7/8/20). The probe’s main telescope, eROSITA, has discovered hundreds of celestial objects, including a bizarre stellar explosion known as a “cow” (SN: 1/21/22). On February 26, the Germans placed eROSITA into safe mode as an action to “freeze co-operation with Russia,” according to a statement from SRG leadership at the Max Planck Institute in Garching, Germany.  

    “This is a standard, reversible, operation mode of the telescope, in which we do not take data, but keep the vital subsystems on,” says Andrea Merloni, an astronomer at the Max Planck Institute for Extraterrestrial Physics, also in Garching, and eROSITA’s project scientist. He declined to comment on any other aspect of the mission or collaboration with Russia.

    The Russian News Agency TASS reported March 1 that Roscosmos intends to estimate the financial loss of that safe-mode action and other European space-related sanctions, and the Russian space agency will then bill “the European side” of the projects.

    ESA, meanwhile, is “assessing the consequences on each of our ongoing programmes conducted in cooperation with the Russian state space agency,” the agency said in its February 28 statement.

    Navigation satellites

    In response to international sanctions against Russia, the head of Roscosmos announced February 26 that the agency was suspending cooperation with the European spaceport in Kourou, French Guiana, and withdrawing its dozens of employees from the site. Several space missions were set to launch from this location via a Russian Soyuz rocket in the next year, including a pair of European navigation satellites in early April.

    These satellites would have joined with the already-launched two dozen that make up the Galileo navigational system, the European answer to the United States’ GPS system. Two additional Galileo satellites are also in orbit, but they were placed incorrectly and instead focus on science and search and rescue (SN: 12/10/18).

    OneWeb internet network

    The U.K. company OneWeb, which is building a space-based internet network with hundreds of low-Earth satellites, is also facing a launch postponement.

    A Soyuz rocket was scheduled to send up a few dozen OneWeb satellites March 4, one of a series of launches aimed at completing the network in 2022. But in the early hours of March 2, the head of Roscosmos tweeted the space agency wouldn’t launch the satellites without a guarantee from the company that they wouldn’t be used for military purposes. He also demanded the U.K. government sell its share of the mission, which it has refused to do.

    Venera-D mission to Venus

    The Russian-Ukraine war has also affected U.S. space activities, but to a lesser extent than its impact on its European counterparts. NASA has relationships with several commercial partners, so the agency relies less on Roscosmos. But NASA is still feeling some effects.

    For instance, in retaliation to U.S. sanctions, the head of Roscosmos tweeted on February 26 that NASA’s participation in the Russian-led Venera-D mission to Venus would be “inappropriate.” This mission will include an orbiter, lander and surface station, and it will focus on understanding Venus’s former and present habitability.

    However, Venera-D won’t launch until late this decade, and NASA has been involved only in some planning groups. The U.S. space agency already has two of its own Venus missions in the works (SN: 6/02/21).

    International Space Station

    While many areas of cooperation in space with Russia are fraying, the International Space Station collaboration so far remains unchanged. “NASA continues working with all our international partners, including the State Space Corporation Roscosmos, for the ongoing safe operations of the International Space Station,” NASA public affairs officer Joshua Finch, at Kennedy Space Center in Cape Canaveral, said in an e-mailed statement.

    Currently, there are two Russian cosmonauts, four NASA astronauts and one ESA astronaut aboard the station. Later this month, a Russian Soyuz capsule is set to return the two cosmonauts and one of the NASA astronauts to Earth, landing in Kazakhstan as scheduled, Finch said.

    However, during a March 1 NASA Advisory Council meeting, Wayne Hale, a former NASA associate administrator, recommended the U.S. space agency consider contingencies in case Russia no longer collaborates on the space station. At the same meeting the following day, former U.S. representative Jane Harman recommended that NASA think about what cooperation with Russia will look like going forward. More

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    A fast radio burst’s unlikely source may be a cluster of old stars

    In a galaxy not so far away, astronomers have located a surprising source of a mysterious, rapid radio signal.

    The signal, a repeating fast radio burst, or FRB, was observed over several months in 2021, allowing astronomers to pinpoint its location to a globular cluster — a tight, spherical cluster of stars — in M81, a massive spiral galaxy 12 million light-years away. The findings, published February 23 in Nature, are challenging astronomers’ assumptions of what objects create FRBs.

    “This is a very revolutionary discovery,” says Bing Zhang, an astronomer at the University of Nevada, Las Vegas who was not involved in the study. “It is exciting to see an FRB from a globular cluster. That is not the favorited place people imagined.”

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    Astronomers have been puzzling over these mysterious cosmic radio signals, which typically last less than a millisecond, since their discovery in 2007 (SN: 7/25/14). But in 2020, an FRB was seen in our own galaxy, helping scientists determine one source must be magnetars — young, highly magnetized neutron stars with magnetic fields a trillion times as strong as Earth’s (SN: 6/4/20).

    The new findings come as a surprise because globular clusters harbor only old stars — some of the oldest in the universe. Magnetars, on the other hand, are young leftover dense cores typically created from the death of short-lived massive stars. The magnetized cores are thought to lose the energy needed to produce FRBs after about 10,000 years. Globular clusters, whose stars average many billions of years old, are much too elderly to have had a sufficiently recent young stellar death to create this type of magnetar. 

    To pinpoint the FRB, astronomer Franz Kirsten and colleagues used a web of 11 radio telescopes spread across Europe and Asia to catch five bursts from the same source. Combining the radio observations, the astronomers were able to zero in on the signal’s origins, finding it was almost certainly from within a globular cluster.

    “This is a very exciting discovery because it was completely unexpected,” says Kirsten, of ASTRON, the Netherlands Institute for Radio Astronomy, who is based at the Onsala Space Observatory in Sweden.

    The new FRB might still be caused by a magnetar, the team proposes, but one that formed in a different way, such as from old stars common in globular clusters. For example, this magnetar could have been created from a remnant stellar core known as a white dwarf that had gathered too much material from a companion star, causing it to collapse.

    “This is a [magnetar] formation channel that has been predicted, but it’s hard to see,” Kirsten says. “Nobody has actually seen such an event.”

    Alternatively, the magnetar could have been formed from the merger of two stars — such as a pair of white dwarfs, a pair of neutron stars or one of each — in close orbit around one another, but this scenario is less likely, Kirsten says. It’s also possible the FRB source isn’t a magnetar at all but a very energetic millisecond pulsar, which is also a type of neutron star that could be found in a globular cluster, but one that has a weaker magnetic field.

    To date, only a few FRB sources have been precisely pinpointed, and their locations are all in or close to star-forming regions in galaxies. Besides adding a new source for FRBs, the findings suggest that magnetars created from something other than the death of young stars might be more common than expected. More

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    An ancient impact on Earth led to a cascade of cratering

    A bevy of craters formed by material blasted from the carving of another, larger crater — a process dubbed secondary cratering — have finally been spotted on Earth. Several groupings of craters in southeastern Wyoming, including dozens of pockmarks in all, have the hallmarks of secondary cratering, researchers report February 11 in GSA Bulletin.

    When an asteroid or another type of space rock smacks into a planet or moon, it blasts material from the surface and creates a crater (SN: 12/18/18). Large blocks of that material can be thrown far from the initial crater and blast out their own holes when they land, explains Thomas Kenkmann, a planetary scientist at the Albert Ludwig University of Freiburg in Germany. Astronomers have long observed secondary cratering on our moon, Mars and other orbs in the solar system, but never on Earth.

    When Kenkmann and his colleagues first investigated a series of craters near Douglas, Wyo., in 2018, they thought the pockmarks were formed by fragments of a large meteorite that had broken up in the atmosphere. But Kenkmann and his team later discovered similar groups of craters of the same age, somewhere around 280 million years old, throughout the region.

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    Altogether, the team found more than 30 impact craters that range between 10 and 70 meters in diameter at six different locales. Based on subtle but distinct differences in the alignment of elliptical craters in the groups, the researchers suggest that the impactors that blasted each set of craters struck the ground from slightly different directions.

    The impactors that created these secondary craters probably ranged between 4 and 8 meters in diameter and struck the ground at speeds between 2,520 and 3,600 kilometers per hour, Kenkmann says. Extrapolating the paths of these impactors back to their presumed sources suggests the original crater from which they flew straddles the Wyoming–Nebraska border northeast of Cheyenne.

    The team’s evidence “comes together very well to make a compelling story,” says Gareth Collins, a planetary scientist at Imperial College London who was not involved in the new study.

    The original crater was probably between 50 and 65 kilometers across and was created by an impactor 4 to 5.4 kilometers wide, Kenkmann and the team estimate. The crater is also probably buried under more than 2 kilometers of sediment that accumulated in the 280 million years since it formed. An equivalent amount of sediment eroded away to expose the secondary craters when the Rocky Mountains rose in the meantime.

    “What a fortuitous discovery that these folks have made,” says Beau Bierhaus, a planetary scientist at Lockheed Martin Space Systems in Littleton, Colo. He likens the short geological interval during which these craters could be discovered to the brief period between the time a fossil is first exposed to the elements and when it is eroded to dust.

    Scouring measurements of gravitational and magnetic fields in the region for anomalies could help reveal the buried crater, the researchers note. The team may also look for heavily fractured rock and other evidence of the ancient crater in sediment cores that have been drilled during oil and gas exploration in the region, Kenkmann says. More

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    A rare collision of dead stars can bring a new one to life

    Like a phoenix, some stars may burst to life covered in “ash,” rising from the remains of stars that had previously passed on.

    Two newfound fireballs that burn hundreds of times as bright as the sun and are covered in carbon and oxygen, ashy byproducts of helium fusion, belong to a new class of stars, researchers report in the March Monthly Notices of the Royal Astronomical Society: Letters. Though these blazing orbs are not the first stellar bodies found covered in carbon and oxygen, an analysis of the light emitted by the stars suggests they are the first discovered to also have helium-burning cores.

    “That [combination] has never been seen before,” says study coauthor Nicole Reindl, an astrophysicist from the University of Potsdam in Germany. “That tells you the star must have evolved differently.”

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    The stars may have formed from the merging of two white dwarfs, the remnant hearts of stars that exhausted their fuel, another team proposes in a companion study. The story goes that one of the two was rich in helium, while the other contained lots of carbon and oxygen.These two white dwarfs had already been orbiting one another, but gradually drew together over time. Eventually the helium-rich white dwarf gobbled its partner, spewing carbon and oxygen all over its surface, just as a messy child might get food all over their face.

    Such a merger would have produced a stellar body covered in carbon and oxygen with enough mass to reignite nuclear fusion in its core, causing it to burn hot and glow brilliantly, say Tiara Battich, an astrophysicist from the Max Planck Institute for Astrophysics in Garching, Germany, and her colleagues.

    To test this hypothesis, Battich and her colleagues simulated the evolution, death and eventual merging of two stars. The team found that aggregating a carbon-and-oxygen-rich white dwarf onto a more massive helium one could explain the surface compositions of the two stars observed by Reindl and her colleagues.

    “But this should happen very rarely,” Battich says.

    In most cases the opposite should occur — the carbon-oxygen white dwarf should cover itself with the helium one. That’s because carbon-oxygen white dwarfs are usually the more massive ones. For the rarer scenario to occur, two stars slightly more massive than the sun must have formed at just the right distance apart from each other. What’s more, they needed to have then exchanged material at just the right time before both running out of nuclear fuel in order to leave behind a helium white dwarf of greater mass than a carbon-and-oxygen counterpart.

    The origins story Battich and her colleagues propose demands a very specific and unusual set of circumstances, says Simon Blouin, an astrophysicist from the University of Victoria in Canada, who was not involved with either study. “But in the end, it makes sense.” Stellar mergers are dynamic and complicated events that can unfold in many ways, he says (SN: 12/1/20). “This is just another.” More

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    How ‘hot Jupiters’ may get their weirdly tight orbits

    Strange giant planets known as hot Jupiters, which orbit close to their suns, got kicked onto their peculiar paths by nearby planets and stars, a new study finds.

    After analyzing the orbits of dozens of hot Jupiters, a team of astronomers found a way to catch giant planets in the process of getting uncomfortably close to their stars. The new analysis, submitted January 27 to arXiv.org, pins the blame for the weird worlds on gravitational kicks from other massive objects orbiting the same star, many of which destroyed themselves in the process.

    “It’s a pretty dramatic way to create your hot Jupiters,” says Malena Rice, an astrophysicist at Yale University.

    Hot Jupiters have long been mysterious. They orbit very close to their stars, whirling around in a few days or less, whereas all the giant planets in our solar system lie at vast distances from the sun (SN: 6/5/17). To explain the odd planets, astronomers have proposed three main ideas (SN: 5/11/18). Perhaps the hot Jupiters formed next to their stars and stayed put, or maybe they started off farther out and then slowly spiraled inward. In either case, the planets should have circular orbits aligned with their stars’ equators, because the worlds inherited their paths from material in the protoplanetary disks that gave them birth.

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    The new study, though, favors the third idea: Gravitational interactions with another giant planet or a companion star first hurl a Jupiter-sized planet onto a highly elliptical and inclined orbit that brings it close to its star. In some cases, the planet even revolves the wrong way around its star, opposite the way it spins.

    In this scenario, every time the tossed planet sweeps past its sun, the star’s gravity robs the planet of orbital energy. This shrinks the orbit, gradually making it more circular and less inclined, until the planet becomes a hot Jupiter on a small, circular orbit, realigned to be in the same plane as the star’s equator.

    Stars usually circularize a planet’s orbit before they realign it, and cool stars realign an orbit faster than warm stars do. So Rice and her colleagues looked for relationships between the shapes and tilts of the orbits of several dozen hot Jupiters that go around stars of different temperatures.

    Generally speaking, the team found that the hot Jupiters around cool stars tend to be on well-aligned, circular orbits, whereas the hot Jupiters around warm stars are often on orbits that are elongated and off-kilter. Put another way, many of the orbits around warm stars haven’t yet had time to settle down into their final size and orientation. These orbits still bear the marks of having been shaped by gravitational run-ins with neighboring bodies in the system, the team concludes.

    It’s a “simple, elegant argument,” says David Martin, an astrophysicist at Ohio State University in Columbus who was not involved with this study. “They’re presenting the evidence in a new way that helps strengthen” the idea that other massive objects in the same solar system produce hot Jupiters. He suspects this theory probably explains the majority of these planets.

    But it means that innumerable giant worlds have suffered terrible fates. Some of the planets that hurled their brethren close to their stars ended up plunging into those same stars themselves, Rice says. And many other planets got ejected from their solar systems altogether, so today these wayward worlds wander the deep freeze of interstellar space, far from the light of any sun. More

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    Earth has a second known ‘Trojan asteroid’ that shares its orbit

    A recently found space rock is schlepping along with Earth around the sun. This “Trojan asteroid” is only the second one discovered that belongs to our planet. And it’s probably a visitor.

    Trojan asteroids, which are also found accompanying Mars, Jupiter and Neptune, hang out in two locations near a planet where the gravitational pulls of that planet and the sun balance each other (SN: 10/15/21). Because of this balancing act, these locations are stable spots in space. In 2010, astronomers discovered the first known Earth Trojan — called 2010 TK7 — orbiting within one of these two regions, known as L4, tens of millions of kilometers from Earth and leading our planet around the sun (SN: 8/2/11).

    Now, researchers have found another one. Dubbed 2020 XL5, this roughly 1-kilometer-wide asteroid is also at L4, astronomer Toni Santana-Ros of the University of Barcelona and colleagues report February 1 in Nature Communications.

    The space rock was first spotted in December 2020, and follow-up observations suggested that it might be at L4. To confirm this, Santana-Ros and colleagues observed the asteroid using ground-based telescopes in 2021. Measurements of its brightness let the researchers estimate the asteroid’s size — about three to four times as wide as 2010 TK7. They also scoured archival data and found the object in images dating to 2012.

    “There is no doubt this is an Earth Trojan,” Santana-Ros says. That decade-worth of observations let the team calculate the rock’s orbit thousands of years into the future, confirming the asteroid’s nature. It will hang around at L4 for at least 4,000 years, the team predicts. 2010 TK7, for comparison, will stick around for some 10,000 years.

    Now that scientists know of two just-visiting Earth Trojans, they can envision more. The fact that the team discovered a second object means that 2010 TK7 isn’t a rarity or loner, Santana-Ros says. “It might be part of a family or population.” More

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    Machine learning points to prime places in Antarctica to find meteorites

    The hunt for meteorites may have just gotten some new leads. A powerful new machine learning algorithm has identified over 600 hot spots in Antarctica where scientists are likely to find a bounty of the fallen alien rocks, researchers report January 26 in Science Advances.  

    Antarctica isn’t necessarily the No. 1 landing spot for meteorites, bits of extraterrestrial rock that offer a window into the birth and evolution of the solar system. Previous estimates suggest more meteorites probably land closer to the equator (SN: 5/29/20). But the southern continent is still the best place to find them, says Veronica Tollenaar, a glaciologist at the Université libre de Bruxelles in Belgium. Not only are the dark specks at the surface starkly visible against the white background, but quirks of the ice sheet’s flow can also concentrate meteorites in “stranding zones.”

    The trouble is that so far, meteorite stranding zones have been found by luck. Satellites help, but poring through the images is time-consuming, and field reconnaissance is costly. So Tollenaar and her colleagues trained computers to find these zones more quickly.

    Such stranding zones form when the slow creep of the ice sheet over the land encounters a mountain or hidden rise in the ground. That barrier shifts the flow upward, carrying any embedded space rocks toward the surface.

    Combining a machine learning algorithm with data on the ice’s velocity and thickness, surface temperatures, the shape of the bedrock and known stranding zones, Tollenaar and colleagues created a map of 613 probable meteorite hot spots, including some near existing Antarctic research stations.

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    To date, about 45,000 meteorites have been plucked from the ice. But that’s a fraction of the 300,000 bits of space rock estimated to lie somewhere on the continent’s surface.

    The team has yet to test the map on the ground; a COVID-19 outbreak at the Belgian station in December halted plans to try it during the 2021–2022 field season. It will try again next year. Meanwhile, the team is making these data freely accessible to other researchers, hoping they’ll take up the hunt as well. More

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    The James Webb Space Telescope has reached its new home at last

    The James Webb Space Telescope has finally arrived at its new home. After a Christmas launch and a month of unfolding and assembling itself in space, the new space observatory reached its final destination, a spot known as L2, on January 24.

    But the telescope can’t start doing science yet. There are still several months’ worth of tasks on Webb’s to-do list before the telescope is ready to peep at the earliest light in the universe or spy on exoplanets’ alien atmospheres (SN: 10/6/21).

    “That doesn’t mean there’s anything wrong,” says astronomer Scott Friedman of the Space Telescope Science Institute in Baltimore, who is managing this next phase of Webb’s journey. “Everything could go perfectly, and it would still take six months” from launch for the telescope’s science instruments to be ready for action, he says.

    Here’s what to expect next.

    Life at L2

    L2, technically known as the second Earth-sun Lagrange point, is a spot about 1.5 million kilometers from Earth in the direction of Mars, where the sun and Earth’s gravity are of equal strength. Pairs of massive objects in space have five such Lagrange points, where the gravitational pushes and pulls from these celestial bodies essentially cancel each other out. That lets objects at Lagrange points stay put without much effort.

    The telescope, also known as JWST, isn’t just sitting tight, though. It’s orbiting L2, even as L2 orbits the sun. That’s because L2 is not precisely stable, Friedman says. It’s like trying to stay balanced directly on top of a basketball. If you nudged an object sitting exactly at that point, it would be easy to make it wander off. Circling L2 as L2 circles the sun in a “halo orbit” is much more stable — it’s harder to fall off the basketball when in constant motion. But it takes some effort to stay there.

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    “JWST and other astronomical satellites, which are said to be at L2 but are really in halo orbits, need propulsion to maintain their positions,” Friedman says. “For JWST, we will execute what we call station keeping maneuvers every 21 days. We fire our thrusters to correct our position, thus maintaining our halo orbit.”

    The amount of fuel needed to maintain Webb’s home in space will set the lifetime of the mission. Once the telescope runs out of fuel, the mission is over. Luckily, the spacecraft had a near-perfect launch and didn’t use much fuel in transit to L2. As a result, it might be able to last more than 10 years, team members say, longer than the original five- to 10-year estimate.

    [embedded content]
    Webb’s final destination is a spot in space called L2, about 1.5 million kilometers away from Earth. The telescope will actually orbit L2 as L2 orbits the sun (as shown in this animation). This special “halo orbit” helps the spacecraft stay in place without burning much fuel.

    Webb has one more feature that helps it stay stable. The telescope’s gigantic kitelike sunshield, which protects the delicate instruments from the heat and light of the sun, Earth and the moon, could pick up momentum from the stream of charged particles that constantly flows from the sun, like a solar sail. If so, that could push Webb off course. To prevent this, the telescope has a flap that acts as a rudder, said Webb sunshield manager Jim Flynn of Northrup Grumman in a January 4 news conference.

    Cooling down

    Webb sees in infrared light, wavelengths longer than what the human eye can see. But humans do experience infrared radiation as heat. “We’re essentially looking at the universe in heat vision,” says astrophysicist Erin Smith of NASA’s Goddard Space Flight Center in Greenbelt, Md., a project scientist on Webb.

    That means that the parts of the telescope that observe the sky have to be at about 40 kelvins (–233° Celsius), which nearly matches the cold of space. That way, Webb avoids emitting more heat than the distant sources in the universe that the telescope will be observing, preventing it from obscuring them from view.

    Most of Webb has been cooling down ever since the telescope’s sunshield unfurled on January 4. The observatory’s five-layer sunshield blocks and deflects heat and light, letting the telescope’s mirrors and scientific instruments cool off from their temperature at launch. The sunshield layer closest to the sun will warm to about 85° Celsius, but the cold side will be about –233° Celsius, said Webb’s commissioning manager Keith Parrish in a January 4 webcast.

    “You could boil water on the front side of us, and on the backside of us, you’re almost down to absolute zero,” Parrish said.

    One of the instruments, MIRI, the Mid-Infrared Instrument, has extra coolant to bring it down to 6.7 kelvins (–266° Celsius) to enable it to see even dimmer and cooler objects than the rest of the telescope. For MIRI, “space isn’t cold enough,” Smith says.

    Aligning the mirrors

    Webb finished unfolding its 6.5-meter-wide golden mirror on January 8, turning the spacecraft into a true telescope. But it’s not done yet. That mirror, which collects and focuses light from the distant universe, is made up of 18 hexagonal segments. And each of those segments has to line up with a precision of about 10 or 20 nanometers so that the whole apparatus mimics a single, wide mirror.

    Starting on January 12, 126 tiny motors on the back of the 18 segments started moving and reshaping them to make sure they all match up. Another six motors went to work on the secondary mirror, which is supported on a boom in front of the primary mirror.

    [embedded content]
    Before the James Webb Space Telescope can start observing the universe, all 18 segments of its primary mirror need to act as one 6.5-meter mirror. This animation shows the mirror segments moving, tilting and bending to bring 18 separate images of a star (light dots) together into a single, focused image.

    This alignment process will take until at least April to finish. In part, that’s because the movements are happening while the mirror is cooling. The changing temperature changes the shape of the mirrors, so they can’t be put in their final alignment until after the telescope’s suite of scientific instruments are fully chilled.

    Once the initial alignment is done, light from distant space will first bounce off the primary mirror, then the secondary mirror and finally reach the instruments that will analyze the cosmic signals. But the alignment of the mirror segments is “not just right now, it’s a continuous process, just to make sure that they’re always perfectly aligned,” Scarlin Hernandez, a flight systems engineer at the Space Telescope Science Institute in Baltimore said at a NASA Science Live event on January 24. The process will continue for the telescope’s lifetime.

    Calibrating the science instruments

    While the mirrors are aligning, Webb’s science instruments will turn on. Technically, this is when Webb will take its first pictures, says astronomer Klaus Pontoppidan, also of the Space Telescope Science Institute. “But they’re not going to be pretty,” Pontoppidan says. The telescope will first test its focus on a single bright star, bringing 18 separate bright dots into one by tilting the mirrors.

    After a few final adjustments, the telescope will be “performing as we want it to and presenting beautiful images of the sky to all the instruments,” Friedman says. “Then they can start doing their work.”

    These instruments include NIRCam, the primary near-infrared camera that will cover the range of wavelengths from 0.6 to 5 micrometers. NIRCam will be able to image the earliest stars and galaxies as they were when they formed at least 12 billion years ago, as well as young stars in the Milky Way. The camera will also be able to see objects in the Kuiper Belt at the edge of the solar system and is equipped with a coronagraph, which can block light from a star to reveal details of dimmer exoplanets orbiting it.

    Next up is NIRSpec, the near-infrared spectrograph, which will cover the same range of light wavelengths as NIRCam. But instead of collecting light and turning it into an image, NIRSpec will split the light into a spectrum to figure out an object’s properties, such as temperature, mass and composition. The spectrograph is designed to observe 100 objects at the same time.

    MIRI, the mid-infrared instrument, is kept the coldest to observe in the longest wavelengths, from 5 to 28 micrometers. MIRI has both a camera and a spectrograph that, like NIRCam and NIRSpec, will still be sensitive to distant galaxies and newborn stars, but it will also be able to spot planets, comets and asteroids.

    And the fourth instrument, called the FGS/NIRISS, is a two-parter. FGS is a camera that will help the telescope point precisely. And NIRISS, which stands for near-infrared imager and slitless spectrograph, will be specifically used to detect and characterize exoplanets.

    [embedded content]
    The James Webb Space Telescope’s science instruments are stored behind the primary mirror (as shown in this animation). Light from distant objects hits the primary mirror, then the secondary mirror in front of it, which focuses the light onto the instruments.

    First science targets

    It will take at least another five months after arriving at L2 to finish calibrating all of those science instruments, Pontoppidan says. When that’s all done, the Webb science team has a top secret plan for the first full color images to be released.

    “These are images that are meant to demonstrate to the world that the observatory is working and ready for science,” Pontoppidan says. “Exactly what will be in that package, that’s a secret.”

    Partly the secrecy is because there’s still some uncertainty in what the telescope will be able to look at when the time comes. If setting up the instruments takes longer than expected, Webb will be in a different part of its orbit and certain parts of the sky will be out of view for a while. The team doesn’t want to promise something specific and then be wrong, Pontoppidan says.

    But also, “it’s meant to be a surprise,” he says. “We don’t want to spoil that surprise.”

    Webb’s first science projects, however, are not under wraps. In the first five months of observations, Webb will begin a series of Early Release Science projects. These will use every feature of every instrument to look at a broad range of space targets, including everything from Jupiter to distant galaxies and from star formation to black holes and exoplanets.

    Still, even the scientists are eager for the pretty pictures.

    “I’m just very excited to get to see those first images, just because they will be spectacular,” Smith says. “As much as I love the science, it’s also fun to ooh and ahh.”    More