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Space: From asteroid collisions and moon journeys to stunning telescope images

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For decades, the faintest hint of cosmic pessimism has been limiting expectations if not dreams. Now, we’re in the midst of a new space race

In September this year, more than 10 million kilometres out in space, a little spaceship collided with a large asteroid called Dimorphos.

This was on purpose, a good shot. The mission was to disrupt the orbital path Dimorphos takes around its paired larger asteroid Didymos, which it did, by a lot more even than NASA expected

Neither asteroid was headed for Earth. But if one ever happens to, a solution is now clear. We don’t need to blow it up like Bruce Willis in Armageddon. We’ll just nudge it away. The Double Asteroid Redirection Test (DART) was a striking “proof of concept” experiment, and not even the biggest space story of the year, although NASA administrator Bill Nelson called it “a watershed moment for planetary defence, and a watershed moment for humanity.”

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At the end of 2022, things are looking up, space-wise. Just a few weeks before NASA hit that asteroid bullseye, the first images arrived back on Earth from the new James Webb Space Telescope, stationed out at a stable place in the interplay between Sun and Earth gravity, facing out into the receding darkness. This successor to the 32-year-old Hubble launched last Christmas Day, equipped with, among other fancy things, a Canadian made device called the Near Infrared Imager and Slitless Spectrograph (NIRISS). Already, it is revealing new insights about how the universe’s first galaxies formed out of the remnants of the Big Bang.

Then in November, the Artemis 1 mission set off around the Moon and back on a new spaceship called Orion, carrying humanoid technical mannequins to prove it can one day safely carry human crew, and a new thermal shield to protect them from re-entry temperatures higher than anything previously encountered in crewed spaceflight.

Space news barely took a day off this year. Two days after Orion splashed down in the Pacific Ocean on Dec. 11, a research paper was published about a chance encounter on Mars, in which a huge dust devil, more than 100 metres tall, 25 metres across, and moving about 18 km/h across the surface of Mars happened to run directly over the Perseverance rover, which captured audio as well as video, and beamed it back to Earth.

This whisper of extraterrestrial wind and its detailed acoustic analysis was no major breakthrough, just a minor scientific curiosity by itself, but considered alongside the other major space advancements of 2022, it seemed to herald more wondrous curiosities to come.

Next year, for example, the European Space Agency plans to launch the JUICE mission (Jupiter Icy Moons Explorer) to map the icy moons Ganymede, Callisto and Europa that orbit the solar system’s largest planet. NASA plans both to launch a mission to an asteroid, and to welcome the return of samples from another asteroid, from a mission launched in 2020.

Even the grandest plans and predictions are coming into focus, thanks especially to Artemis, after a couple of initial hiccups delayed the launch. Its explicit goal is eventually to put an outpost space station in lunar polar orbit before sending a crewed mission to the surface and back. An entire generation of space scientists is invested in what would follow, a crewed Mars mission, and the beginning of interplanetary colonization.

Telescopes likewise are opening new horizons, penetrating further back into space and time, in some cases almost as far as possible, according to known physics, back even to light produced at the universe’s creation that has been travelling ever since, stretched into infrared by the expansion of the universe itself. The new James Webb Space Telescope can detect this light 100 times fainter than Hubble.

What its research team can see in the resulting images, as the University of Toronto astronomer Lamiya Mowla puts it, “is not a picture of a point in time. This is a history of the universe.”

It is heady and exciting stuff. Taken together, all this evidence suggests the future of space science and exploration looks a bit more today like it did a generation ago, like an accelerating golden age.

Space is back. It is a subtle shift in our shared cultural outlook to the cosmos, but it’s there. For decades, the faintest hint of cosmic pessimism has been limiting expectations if not dreams.

Maybe there is no grand unified theory to be found in physics, no quantum theory of gravity. Maybe getting to Mars is practically impossible. Maybe life really is a unique fluke. The end of the Space Shuttle program a decade ago threatened to doom the International Space Station, which once promised to be a stepping stone for humans to the cosmos, not the dead-end “tin can” of Space Oddity. Maybe the momentum had left the space project.

The mid-century superpower space race is not only over, but at least one racer has degenerated into an imperial basket case, failing this year at even earthbound conquest. The Russian Soyuz spacecraft remains the workhorse of human transit to the space station, and until recently it was the only way to get there, but this month’s coolant leak was a reminder that it is 20th century technology for a 20th century purpose.

Now there are more space racers than ever before. They include China, of course, and Japan, also India, which will launch Chandrayaan 3 early next year, trying to land a rover on the Moon, and redeem the software glitch that crashed Chandrayaan 2’s landing in 2019.

Private industry has picked up slack in rocketry. SpaceX has proved the benefit of re-usable rockets in launching at a fraction of what NASA spends to launch its new Space Launch System, and plans to soon test its Starship craft, designed for crewed flight both in orbit and eventually to Mars.

Technology has offered up not just new telescopes in space with vastly increased resolution, but also revolutionary new ways of looking, such as gravitational wave astronomy.

In an interview, Mowla reflected on the scientific excitement of the new space telescope. She is an observational astronomer studying the structural evolution of massive galaxies in the early universe with images from both Hubble and Webb, and her work illustrates this renewed sense of promise in space science.

Hubble was launched in the era of floppy disks, before cell phones, with very low memory. “Now we can fit so much data on these chips,” she said. “There is definitely a technological explosion that happened between Hubble and JWST.”

She and colleagues working with new data from Webb recently discovered a galaxy nicknamed The Sparkler, which is interesting because it is both very distant and very old. It was already old when the light detected by Webb started its journey 9 billion years ago.

“So it must be very old,” she said. This was a basic goal of Webb, to see the very first galaxies, composed of the very first stars, and to learn how they first formed, and why today some are ultra diffuse, “like ghosts,” almost transparent, while others are compact and bright.

The Sparkler is good evidence that a lot of the structural formation is happening very early on, Mowla said.

In space, you can only see what used to be, not what presently is. Light moves so fast that it fools us in our everyday lives. We act as if it doesn’t matter, but there’s always a gap, the time it takes light to travel at its constant speed of about a billion kilometres an hour. Light is like the future. You can never truly see it coming. But it gets here quick.

“It’s one of the best parts of living in this universe, that every time you look up in the sky you’re essentially time travelling,” Mowla said. “We can never know what the sun looks like right at this moment, we have to wait 8 minutes to find out.”

It is the same for other stars, only more so, each one a different time away into the past.

“You’re looking at so many points in time at the same time. It gives you shivers, right?” she said.

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Giant prehistoric salmon had tusk-like teeth for defence, building nests

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The artwork and publicity materials showcasing a giant salmon that lived five million years ago were ready to go to promote a new exhibit, when the discovery of two fossilized skulls immediately changed what researchers knew about the fish.

Initial fossil discoveries of the 2.7-metre-long salmon in Oregon in the 1970s were incomplete and had led researchers to mistakenly suggest the fish had fang-like teeth.

It was dubbed the “sabre-toothed salmon” and became a kind of mascot for the Museum of Natural and Cultural History at the University of Oregon, says researcher Edward Davis.

But then came discovery of two skulls in 2014.

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Davis, a member of the team that found the skulls, says it wasn’t until they got back to the lab that he realized the significance of the discovery that has led to the renaming of the fish in a new, peer-reviewed study.

“There were these two skulls staring at me with sideways teeth,” says Davis, an associate professor in the department of earth sciences at the university.

In that position, the tusk-like teeth could not have been used for biting, he says.

“That was definitely a surprising moment,” says Davis, who serves as director of the Condon Fossil Collection at the university’s Museum of Natural and Cultural History.

“I realized that all of the artwork and all of the publicity materials and bumper stickers and buttons and T-shirts we had just made two months prior, for the new exhibit, were all out of date,” he says with a laugh.

Davis is co-author of the new study in the journal PLOS One, which renames the giant fish the “spike-toothed salmon.”

It says the salmon used the tusk-like spikes for building nests to spawn, and as defence mechanisms against predators and other salmon.

The salmon lived about five million years ago at a time when Earth was transitioning from warmer to relatively cooler conditions, Davis says.

It’s hard to know exactly why the relatives of today’s sockeye went extinct, but Davis says the cooler conditions would have affected the productivity of the Pacific Ocean and the amount of rain feeding rivers that served as their spawning areas.

Another co-author, Brian Sidlauskas, says a fish the size of the spike-toothed salmon must have been targeted by predators such as killer whales or sharks.

“I like to think … it’s almost like a sledgehammer, these salmon swinging their head back and forth in order to fend off things that might want to feast on them,” he says.

Sidlauskas says analysis by the lead author of the paper, Kerin Claeson, found both male and female salmon had the “multi-functional” spike-tooth feature.

“That’s part of our reason for hypothesizing that this tooth is multi-functional … It could easily be for digging out nests,” he says.

“Think about how big the (nest) would have to be for an animal of this size, and then carving it out in what’s probably pretty shallow water; and so having an extra digging tool attached to your head could be really useful.”

Sidlauskas says the giant salmon help researchers understand the boundaries of what’s possible with the evolution of salmon, but they also capture the human imagination and a sense of wonder about what’s possible on Earth.

“I think it helps us value a little more what we do still have, or I hope that it does. That animal is no longer with us, but it is a product of the same biosphere that sustains us.”

This report by The Canadian Press was first published April 24, 2024.

Brenna Owen, The Canadian Press

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Giant prehistoric salmon had tusk-like spikes used for defence, building nests: study

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A new paper says a giant salmon that lived five million years ago in the coastal waters of the Pacific Northwest used tusk-like spikes as defense mechanisms and for building nests to spawn.

The initial fossil discoveries of the 2.7-metre-long salmon in Oregon in the 1970s were incomplete and led researchers to suggest the fish had fang-like teeth.

The now-extinct fish was dubbed the “saber-tooth salmon,” but the study published in the peer-reviewed journal PLOS One today renames it the “spike-toothed salmon” and says both males and females possessed the “multifunctional” feature.

Study co-author Edward Davis says the revelation about the tusk-like teeth came after the discovery of fossilized skulls at a site in Oregon in 2014.

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Davis, an associate professor in the department of earth sciences at the University of Oregon, says he was surprised to see the skulls had “sideways teeth.”

Contrary to the belief since the 1970s, he says the teeth couldn’t have been used for any kind of biting.

“That was definitely a surprising moment,” Davis says of the fossil discovery in 2014. “I realized that all of the artwork and all of the publicity materials … we had just made two months prior, for the new exhibit, were all out of date.”

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SpaceX sends 23 Starlink satellites into low-Earth orbit

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April 23 (UPI) — SpaceX launched 23 Starlink satellites into low-Earth orbit Tuesday evening from Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida.

Liftoff occurred at 6:17 EDT with a SpaceX Falcon 9 rocket sending the payload of 23 Starlink satellites into orbit.

The Falcon 9 rocket’s first-stage booster landed on an autonomous drone ship in the Atlantic Ocean after separating from the rocket’s second stage and its payload.

The entire mission was scheduled to take about an hour and 5 minutes to complete from launch to satellite deployment.

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The mission was the ninth flight for the first-stage booster that previously completed five Starlink satellite-deployment missions and three other missions.

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