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A second planet might orbit the closest star to the sun, and astronomers think it's a super-Earth – Business Insider

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The closest star to the sun might have a second planet in its orbit.

Proxima Centauri is our nearest neighboring star; it’s just 4.2 light-years away. It has one planet that astronomers know of, a potentially habitable world called Proxima b.

But in a new study, researchers from Italy’s National Institute for Astrophysics report that they have observed changes in the star’s activity that indicate it could have another planet. They dubbed the world Proxima c in their paper, which was published Wednesday in the journal Science Advances.

The potential new planet seems to be a super-Earth – the term for a planet with a mass larger than Earth but significantly smaller than the ice giant Neptune.

„Proxima Centauri is the nearest star to the sun, and this detection would make it the closest planetary system to us,“ astronomer Mario Damasso, the paper’s lead author, told Business Insider in an email.

Proxima c (if it exists) is probably not habitable – given its distance from its star, the planet is probably freezing or shrouded in a suffocating hydrogen-helium atmosphere. But its proximity to us could offer a unique opportunity to study another star system.

Proxima c could be a super-Earth in an unexpected place

Foto: An artist’s illustration of Earth-sized planets.sourceNASA/JPL-Caltech/R. Hurt (SSC-Caltech)

If it’s real, Proxima c should not exist where it is.

Astronomers think super-Earths form around the „snowline“: the closest distance to a star where water can become ice. That’s because icy solids accumulate in that region when a star system is in its infancy, helping to form planets.

Proxima c is far beyond that snowline, though, so its existence could challenge that theory.

snowline star planetary system

Foto: An artist’s impression of the water snowline around a young star.sourceA. Angelich (NRAO/AUI/NSF)/ALMA (ESO/NAOJ/NRAO)

Then again, researchers still aren’t sure whether planet exists at all.

The team discovered Proxima c using a technique called radial velocity. It works like this: Planets tug slightly on their stars as they orbit. When the star’s position moves, even in this small way, it changes the colors of its light. If those changes are cyclical, that suggests the cause is an orbiting planet.

radial velocity exoplanet detection method

Foto: The radial velocity technique involves watching stars for changes in the color of their light. That could indicate a star is moving slightly as a planet orbits it.sourceNASA

Damasso’s team identified this type of cyclical change in Proxima Centauri’s light, and determined that it is unrelated to the movements of the planet Proxima b.

That suggested the presence of another planet, though Damasso said the researchers still „cannot discard the possibility that the signal is actually due to the activity of the star.“

So the team hopes to find more clues in data from the Gaia space telescope.

Help from Gaia and James Webb

Gaia mapping the stars of the Milky Way

Foto: An artist’s illustration of the Gaia space telescope observing the Milky Way.sourceESA

The Gaia telescope launched in December 2013 with the ambitious goal of making a 3D map of the galaxy.

„Gaia is still observing, and we calculated in its final data release there will be enough data to confirm or disprove the existence of Proxima c,“ Fabio Del Sordo, a co-author of the paper and an astrophysicist at the University of Crete in Greece, told Business Insider via email.

The next release of Gaia’s data is planned for this summer, followed by another in 2021. The timeline for the full data release has not yet been announced.

While Damasso and Del Sordo wait for that, they’re working with another team to scan photos of Proxima Centauri in search of signs of a second orbiting planet.

„Direct imaging may give results in a shorter time, but it cannot give a definitive answer,“ Del Sordo said. „In other words, if we will not see anything in the image, it doesn’t necessarily mean Proxima c does not exist.“

Another telescope, NASA’s upcoming James Webb Space Telescope (JWST), could help researchers answer these questions, too.

James Webb telescope

Foto: The primary mirror of NASA’s James Webb Space Telescope, consisting of 18 hexagonal mirrors, in the clean room of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, October 28, 2016.sourceNASA/Chris Gunn

The telescope is slated to launch in March 2021, equipped with a 21-foot-wide beryllium mirror and new infrared technology to make it sensitive to longer wavelengths of infrared light.

That could help astronomers study nearby stars and, specifically, Proxima c, in great detail.

„It will surely be a target for JWST, but since the planet is likely very cold, we do not know if JWST will be able to detect it,“ Del Sordo said.

Even if James Webb can’t spot Proxima c, its neighboring planet, Proxima b, will be a prime target.

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Powerful gases ripping a hole in the ozone

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Half of Arctic climate change between 1955 and 2005 may be attributed to ozone-depleting substances banned in 1987 by the Montreal Protocol.
Image: Mario Tama / Getty Images
They were once abundant, in our hairsprays, bug sprays, and refrigerators. And then scientists figured out these substances ripped a hole in the ozone layer, leading to a 1987 plan to phase them out that over time would be agreed to by every country in the world.

More than three decades later, researchers have made a new discovery.

Ozone-depleting substances do more than just gnaw at Earth’s protective layer. They’re also greenhouse gases, so they contribute to the planet’s overall warming by trapping heat, too. And now we may know just how much these substances have contributed to Arctic warming, thanks to a study published in the science journal Nature on Monday.

Between 1955 and 2005, ozone-depleting gases caused half of Arctic climate change (and a third of overall global warming), the study finds. This is primarily due to their heat-trapping qualities, not their ozone munching. The Arctic has seen rapidly melting sea ice for years and is warming faster than the rest of the world. When the sea ice melts in the Earth’s northernmost region, sea levels rise across the globe leading to potential flooding.

Between 1955 and 2005, ozone-depleting gases caused half of Arctic climate change.

These ozone-depleting gases include chlorofluorocarbons (CFCs), which we’ve been cracking down on since the global agreement known as the Montreal Protocol was finalized 33 years ago. CFCs, which include propellants and refrigerants, have been around since the 1920s and 1930s. Their popularity peaked in the late 20th century and have been on the decline since the Montreal Protocol.

To quantify the climate impact of ozone-depleting gasses, scientists from Columbia University, the Institute for Atmospheric and Climate Sciences in Switzerland, and University of Toronto used climate models to run a variety of simulations. In one, they tested what would happen if stratospheric ozone and the pesky gases that hurt it stayed at 1955 levels. Research on CFCs’ climate impacts beyond ozone depletion is scant, even though they can trap more heat than climate change poster child carbon dioxide, the study notes.

The study’s findings not only give an extra gold star to the much-acclaimed Montreal Protocol, but also provide a bit of hope when so much climate change research focuses on doom and gloom.

“Our findings also have implications for the future because the phase-out of [ozone-depleting substances], which is well under way, will substantially mitigate Arctic warming and sea-ice melting in the coming decades,” the study explains.

Indeed, Cecilia Bitz, a climate scientist at the University of Washington in Seattle who was not involved in the study, told Nature, “It’s a very important paper because it has a little shred of optimism.”

Don’t get too excited just yet, though. More studies that replicate these findings need to be done to corroborate the evidence, Bitz, the study authors, and other scientists say.

Then there’s also the problem of CFCs still being used despite global crackdowns. For example, China is struggling to tamp down on illegal CFC production. In addition, we’ve just begun to tackle hydrofluorocarbons (HFCs), which air conditioner and refrigerator manufacturers turned to when they were blocked from CFCs, on a global scale. HFCs are less harmful for the ozone than CFCs, but like their loathed counterpart, they’re more powerful than carbon dioxide when it comes to trapping heat.

And to be clear, weakening the ozone is still a very bad trait to have. Scientists expect it’ll take another 50 years before the ozone hole over Antarctica is back to its 1980 level.

Sorry to be a downer.

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'Dancing dragon' feathered dinosaur fossil discovered in China – CNN

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Researchers named the dinosaur Wulong bohaiensis, which translates to “a dancing dragon.”
The dinosaur was about the size of a raven but double its length with a long, bony tail. Its entire body was covered with feathers, complete with two plumes at the tail’s end.
Despite its small size, it had a fierce, narrow face and a mouth full of sharp teeth. Like a bird, it had small, light bones and wing-like forelimbs. And there were also a number of feathers on its legs.
The fossil was initially discovered in the fossil-filled Jehol Province a decade ago by a farmer and was placed in China’s Dalian Natural History Museum.
Researchers, including Ashley Poust, a postdoctoral researcher at the San Diego Natural History Museum, later analyzed the fossil (at the time, Poust was still a student at Montana State University).
Insects trapped in amber show that lice munched on feathered dinosaurs
The findings were published last week in the journal The Anatomical Record.
“The new dinosaur fits in with an incredible [range] of feathered, winged animals that are closely related to the origin of birds,” Poust, the study’s author, said. “Studying specimens like this not only shows us the sometimes surprising paths that ancient life has taken, but also allows us to test ideas about how important bird characteristics, including flight, arose in the distant past.”
An artist rendering of what Wulong bohaiensis might have looked like. An artist rendering of what Wulong bohaiensis might have looked like.
This dinosaur was a juvenile when it died, according to its bones, but its feathers resembled that of a mature adult. This suggests that the feathers grew quickly, unlike modern birds, which take time to grow their mature feathers.
“Either the young dinosaurs needed these tail feathers for some function we don’t know about, or they were growing their feathers really differently from most living birds,” Poust said.
Trapped in place: A weird ancient bird foot in amber and the lizard in a Microraptor's stomachTrapped in place: A weird ancient bird foot in amber and the lizard in a Microraptor's stomach
The dinosaur was an early relative of Velociraptors, which lived 75 million years ago. Its contemporaries would have been Microraptors, small feathered dinosaurs that resembled birds.
The researchers actually sliced into several bones from the fossil and studied them with microscopes to understand the different regions of the skeleton. They also compared it to a close relative that also appeared more mature, known as the Sinornithosaurus.
'Frozen dragon of the north wind' was one of the largest animals to ever fly'Frozen dragon of the north wind' was one of the largest animals to ever fly
Surprisingly, that dinosaur was also still growing when it died. The researchers said that histology, or cutting up the bones, was the only way for them to truly know the life stage of the dinosaurs when they died.
Fluffy dinosaurs used to live at the South Pole, scientists sayFluffy dinosaurs used to live at the South Pole, scientists say
“We’re talking about animals that lived twice as long ago as T. rex, so it’s pretty amazing how well-preserved they are,” Poust said. “It’s really very exciting to see inside these animals for the first time.”
Fossils from the Jehol Province have painted a portrait of the diverse life that once flourished there. It’s an area in northeastern China full of exceptionally preserved fossil discoveries that has been studied for the past 90 years.
A closer look at the skull, along with a detailed drawing.A closer look at the skull, along with a detailed drawing.
Researchers learned that birds, pterosaurs and bird-like dinosaurs all lived in the environment at the same time. This is also when flowering plants initially began to flourish.
“There was a lot of flying, gliding and flapping around these ancient lakes,” Poust said. “As we continue to discover more about the diversity of these small animals, it becomes interesting how they all might have fit into the ecosystem. It was an alien world, but with some of the earliest feathers and earliest flowers, it would have been a pretty one.”

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Space rock twice the size of Big Ben to skim past Earth – MENAFN.COM

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(MENAFN – IANS)

Washington, Jan 20 (IANS) NASA is closely monitoring an asteroid with an estimated diameter of about 755 feet — larger than the Golden Gate Bridge tower or more than twice the height of London’s Big Ben — that is currently heading towards Earth and is expected to skim past the planet on Monday.

Flying towards the planet at a speed of over 61,500 miles per hour, the Near-Earth Object (NEO) is big enough to destroy an entire city if collides with the Earth.

The approaching asteroid has been identified as “2020 AQ1”.

According to Express.co.uk, the asteroid will make its closest Earth approach on January 20 at around 2.54 am EST (1.24 pm India time).

The European Space Agency (ESA) has identified 21,655 NEO asteroids and 109 NEO comets.

The asteroid will hurtle past the planet on what astronomers have described as a “close approach” trajectory.

NASA’s trackers estimate the rock measures somewhere in the range of 328 feet -754 feet across – more than twice the height of London’s Big Ben.

Last September, a pair of asteroids flew past the Earth.

“These asteroids have been well observed and their orbits are very well known,” said NASA’s Planetary Defence Officer Lindley Johnson.

“Both of these asteroids are passing at about 14 lunar distances from the Earth, or about 3.5 million miles away, but small asteroids pass by Earth this close all the time,” he added.

–IANS

na/ksk/

MENAFN2001202002310000ID1099574382

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