Connect with us


Study predicts Arctic rainy days will double by 2100



The study’s authors, researchers from China and the Netherlands, said more frequent and intense rainfall in the Arctic is expected to increase permafrost melt, releasing large amounts of greenhouse gases, as well as reduce snow cover, and speed up sea-ice loss.

Genius Dog 336 x 280 - Animated

They said it’s also anticipated to result in more rain-on-snow events, where rain falls on existing snowpack and freezes, resulting in an icy crust on top of or within the snow. That can have serious consequences for foraging animals like reindeer, as their food is trapped under the ice, and socio-economic impacts for people who rely on them for food, clothing, transportation and cultural practices.

“Even ordinary rainfall can be regarded as an extreme event in polar regions,” Dou said.

Mark Serreze, director of the National Snow and Ice Data Center with the University of Colorado Boulder, who was not involved in the recent study, researches rain-on-snow events and their impact on human environment systems like reindeer herding. He said there have been cases where tens of thousands of reindeer and muskox have died because they couldn’t forage following rainfall.

“The impacts can extend through generations,” he said, noting it can lead to increased calf mortality. “These are pretty big effects and the real concern is that we will see more of these as the climate change occurs.”

Serreze said that in a warmer environment, the atmosphere can carry more water vapour, resulting in more precipitation. A warmer climate also results in more rain than snow.

The study found the predicted precipitation changes are largely due to rapid warming in the Arctic, which is heating up three times faster than the global average. The increase in total precipitation was also a contributing factor.

Other scientists agree the Arctic will become wetter in the 21st century.

Michelle McCrystall is a post-doctoral researcher with the University of Manitoba’s Centre for Earth Observation Science. She was the lead author of a study published last November, which predicted the Arctic could see more rain than snow as soon as 2050, decades earlier than previously thought.

McCrystall said data from weather stations indicates the region is already seeing the transition to less snow and more rain.

“What really astounded us was kind of the rate at which change happens,” she said.

McCrystall said other potential impacts from the shift to a rainier Arctic include changes in ocean circulation and sea levels due to an influx of fresh water, and an increase in phytoplankton as sea-ice warms. She said changes in the Arctic could also affect the climate at lower latitudes, pointing to a 2018 snowstorm across much of Europe, dubbed the “Beast from the East,” which was caused by the loss of ice in the Barents Sea.

“There is very much local-scale changes happening, but it can affect the Northern Hemisphere climate as well.”

This report by The Canadian Press was first published Oct. 8, 2022.


This story was produced with the financial assistance of the Meta and Canadian Press News Fellowship.

Emily Blake, The Canadian Press

Source link

Continue Reading


Mars at Opposition 2022: The Full Moon Occults Mars Wednesday Night – Universe Today



A rare event transpires Wednesday night, as the Full Moon occults Mars near opposition.

Have you checked out Mars lately? The Red Planet currently rides high to the east at dusk, rising as the Sun sets. We call this opposition season, the biannual span when Mars passes closest to the Earth and offers observers optimal views of the planet. Mars opposition 2022 is special however, as three events converge in one night: Mars at opposition, the Moon reaches Full, and the Moon occults (passes in front of) Mars, all on the evening/morning of Wednesday/Thursday, December 7th/8th.

Genius Dog 336 x 280 - Animated

Celestial Dates with Destiny

You can see how the action around Mars stacks up in the first week of December:

1st- Mars passes nearest Earth (2:00 Universal Time/UT)

8th-Full Moon (4:00 UT)

8th-Mars Lunar Occultation (4:00 UT)

8th-Mars at Opposition (5:00 UT)

Note that Mars is closest to the Earth a week prior to opposition. This occurs for two reasons: while the Earth is moving towards perihelion in January (that is, we’re moving towards the Sun in December, but away from Mars), the Red Planet is doing the opposite, headed towards aphelion on May 30, 2023, just under six months after this week’s opposition. This makes up for the 900,000-odd kilometer difference as Mars is 0.55 Astronomical Units (AU, or 81.5 million kilometers) from Earth on the 1st, but sits 82.4 million kilometers from Earth at opposition.

Mars from November 21st as it nears opposition. Image credit and copyright: Damian Peach.

In fact, we’re currently trending towards a cycle of unfavorable oppositions for Mars now, which will bottom out in February 2027 when Mars only reaches an apparent diameter of 13.8” as seen from the Earth. After 2027, Mars oppositions will slowly start to become more favorable again.

No Missions to Mars

Unfortunately, this Mars launch window also marks a sad milestone: for the first time since 2009, no mission will catch the biannual pre-opposition window to head to Mars. The European Space Agency’s ExoMars Rosalind Franklin rover was set to make the trip until Russia invaded Ukraine early this year, forcing ESA to look for another launch carrier and lander. ESA still hopes to get the rover to Mars by 2030.

The occultation visibility footprint for Wednesday night’s event. Credit: Occult 4.2.

‘Standing in the Shadow’ as the Moon occults Mars

But it’s Wednesday night’s occultation of Mars by the Full Moon that makes the 2022 opposition special. Opposition and the occultation plus the Full Moon all occur within an hour of each other. This is pretty rare: the near-Full Moon hasn’t occulted a naked eye planet or bright star since July 2019 (Saturn) and won’t do so again until May 24, 2024 (Antares), This is also the last of two occultations of Mars by the Moon for 2022, The Moon will occult Mars five times in 2023, though none are as favorable as the December’s event. The December ‘Long Night’s Moon’ nearest to the southward equinox also rides high in the sky for northern hemisphere observers, another plus.

Dec 6
Tuesday, December 6th at dusk, looking eastward. Credit: Stellarium.

This is also the closest Mars opposition versus a Full Moon with a lunar occultation for the 21st century. 21st century occultations of Mars near (less than 24 hours) from Full Moon also occur on December 24, 2007, January 14, 2025, February 5, 2042, May 28, 2048, February 27, 2059, and finally on April 27th 2078, which also features a shallow penumbral lunar eclipse.

The lunar occultation ‘footprint’ for Wednesday night’s occultation spans most of North America and Europe, with only the southeast U.S. missing out. Mars is 17” across during the event, shining at magnitude -1.9. The Moon will take just over half a minute to cover Mars during the occultation.

A sped up view of Wednesday night’s occultation event. Credit: Stellarium.

When to Watch

Here’s a table for select North American and European cities in the path of the occultation, with ingress/egress times. You can see an extensive list of sites and times here.

City Ingress Egress
Detroit 3:20UT/10:20PM EST 4:09UT/11:09PM EST
Dallas 2:54UT/8:54PM CST 3:28UT/9:28PM CST
Los Angeles 2:30UT/6:30PM PST 3:30UT/7:30PM PST
Seattle 2:51UT/6:51PM PST 3:50UT/7:50PM PST
London 5:00UT/5:00AM BST 6:00UT/6:00 AM BST
Helsinki 4:55UT/6:55AM EET 5:39UT/7:39 AM EET
Table credit: Dave Dickinson.

Mars will be bright enough to follow riiiiiight up to the limb of the Full Moon during the event. The occultation occurs in the early morning hours for Europe on Thursday December 8th, and late in the evening of December 7th for North America. The disappearance of Mars behind the Moon will be visible even to the unaided eye, though binoculars or a small telescope will definitely help you enjoy the view.

Looking back from Mars, you’d be treated to an even stranger view, as the Moon transits the slim crescent Earth, just scant degrees from the Sun.

Moon transit
The Moon transits the Earth Wednesday night, as seen from Mars. Credit: Starry Night.

The Moon occults Mars: Weather Prospects, Watching Live

As of writing this, weather prospects for the contiguous United States (CONUS) look to favor the central northern states and the U.S. southwest.

Wx prospects
Weather prospects across CONUS for Wednesday night’s occultation. Credit: NOAA.

Clouded out or simply live outside of the occultation footprint? Astronomer Gianluca Masi has you covered, with a live webcast as the Moon occults Mars, starting at 4:00 UT/11:00 PM EST Wednesday night.

Mars near the crescent Moon from 2020. Image credit and copyright: Efrain Morales Rivera.

The Moon Occults Mars: Spotting a ‘Daytime’ Red Planet

Finally… ever seen Mars in the daytime? It’s certainly possible near opposition… and the nearby Full Moon offers an excellent guide to complete this unusual feat of visual athletics. In North America, I’d start looking for Mars near the Moon just before local sunset, while in Europe, your best bet is to follow Mars near the Moon low to the West, after local sunrise.

Good luck, clear skies, and don’t miss this week’s unique, triple play dance of the Moon and Mars.

Adblock test (Why?)

Source link

Continue Reading


Webb telescope promises new age of the stars – RFI English



Issued on: 07/12/2022 – 07:06Modified: 07/12/2022 – 07:05

Paris (AFP) – The James Webb Space Telescope lit up 2022 with dazzling images of the early universe after the Big Bang, heralding a new era of astronomy and untold revelations about the cosmos in years to come.

Genius Dog 336 x 280 - Animated

The most powerful observatory sent into space succeeds the Hubble telescope, which is still operating, and began transmitting its first cosmic images in July.

“It essentially behaves better than expected in almost every area,” said Massimo Stiavelli, head of the Webb mission office at the Space Telescope Science Institute, in Baltimore.

Already scientists say the Webb telescope, now orbiting the sun at a million miles (1.6 million kilometres) from Earth, should last 20 years, twice its guaranteed lifetime.

James Webb telescope provides new view of the universe © / AFP

“The instruments are more efficient, the optics are sharper and more stable. We have more fuel and we use less fuel,” said Stiavelli.

Stability is vital for the clarity of the images.

“Our requirement was similar to that of Hubble, in terms of pointing accuracy. And we ended up being seven times better,” the mission office chief added.

Public appetite for the discoveries has been fed by the colouring of the telescope’s images.

Light from the most distant galaxies has been stretched from the visible spectrum, viewable by the naked eye, to infrared — which Webb is equipped to observe with unprecedented resolution.

The rings of Neptune, high-altitude methane-ice clouds

The rings of Neptune, high-altitude methane-ice clouds © Space Telescope Science Institut / ESA/WEBB/AFP/File

This enables the telescope to detect the faintest glimmers from the distant universe at an unprecedented resolution, to see through the veil of dust that masks the emergence of stars in a nebula and to analyse the atmosphere of exoplanets, which orbit stars outside our solar system.

18 petals

“The first year (of observation) is a way to test out the tool for the small rocky planets in the habitable zone that could potentially be like Earth,” said Lisa Kaltenegger, associate professor in Astronomy at Cornell University.

“And the tests are beautiful. They’re spectacular.”

Webb blasted off aboard an Ariane 5 rocket at the end of 2021 crowning a 30-year project at the US space agency NASA.

It took 10,000 people and 10 billion dollars to put the 6.2-tonne observatory into space.

The Webb telescope's infrared sets off a kaleidoscope of colours for the 'Pillars of Creation'(R) compared to the Hubble telescope's 2014 view by visible light

The Webb telescope’s infrared sets off a kaleidoscope of colours for the ‘Pillars of Creation'(R) compared to the Hubble telescope’s 2014 view by visible light © Space Telescope Science Institut / NASA/ESA/CSA/AFP/File

En route to final orbit, Webb deployed a five-layer sunshield the size of a tennis court followed by a 6.5 metre primary mirror made up of 18 hexagonal, gold-coated segments or petals.

Once calibrated to less than a millionth of a metre, the 18 petals began to collect the light pulsing stars.

Last July 12, the first images underlined Webb’s capabilities unveiling thousands of galaxies, some dating back close to the birth of the Universe, and a star nursery in the Carina nebula.

Jupiter has been captured in incredible detail which is expected to help understand the workings of the giant gas planet.

‘Too many’ galaxies

The blue, orange and grey tones of the images from the “Pillars of Creation”, giant dust columns where stars are born, proved captivating.

Scientists saw the revelations as a way of rethinking their models of star formation.

Researchers using the new observatory have found the furthest galaxies ever observed, one of which existed just 350 millions years after the Big Bang some 13.8 billion years ago.

The galaxies appear with extreme luminosity and may have started forming 100 million years earlier than theories predicted.

“In the distant Universe, we have an excess of galaxies compared to models,” David Elbaz, scientific director for astrophysics at France’s Alternative Energies and Atomic Energy Commission, told AFP.

Another surprise has been that where Hubble essentially observed irregular shaped galaxies, the precision of the Webb telescope produces magnificent spiral galaxies similar to our own.

The first infrared image from the James Webb Space Telescope is seen during a briefing with US President Joe Biden and National Aeronautics and Space Administration (NASA) officials in the South Court Auditorium at the White House in Washington, DC, on July 11, 2022.The JWST is the most powerful telescope launched into space and it reached its final orbit around the sun, approximately 930,000 miles from Earths orbit, in January, 2022. The technological improvements of the JWST and distance from the sun will allow scientists to see much deeper into our universe with greater detail.

The first infrared image from the James Webb Space Telescope is seen during a briefing with US President Joe Biden and National Aeronautics and Space Administration (NASA) officials in the South Court Auditorium at the White House in Washington, DC, on July 11, 2022.The JWST is the most powerful telescope launched into space and it reached its final orbit around the sun, approximately 930,000 miles from Earths orbit, in January, 2022. The technological improvements of the JWST and distance from the sun will allow scientists to see much deeper into our universe with greater detail. © Handout / NASA/AFP/File

This has led to musings over a potential universal model which could be one of the keys to star formation.

Webb also opened up a profusion of clusters of millions of stars leading, which could be the potential missing link between the first stars and the first galaxies.

In the field of exoplanets, Webb honed in on a faraway gas giant called WASP-96 b, which was discovered in 2014.

Nearly 1,150 light-years from Earth, WASP-96 b is about half the mass of Jupiter and zips around its star in just 3.4 days

Webb provided the first confirmation that carbon dioxide is present in the atmosphere of Wasp 39-b.

But for Stiavelli, “Some of the big things either haven’t been observed yet, or haven’t been revealed yet.”

Adblock test (Why?)

Source link

Continue Reading


NASA Artemis I – Flight Day 21: Orion Spacecraft Leaves Lunar Sphere of Influence, Heads for Home – SciTechDaily



On flight day 20 of the Artemis I mission, Orion captured the Moon on the day of return powered flyby. The burn, which lasted 3 minutes, 27 seconds, committed the spacecraft to a December 11 splashdown. Credit: NASA

On Flight Day 21 of the Artemis I mission, Orion exited the lunar sphere of gravitational influence. It occurred at 1:29 a.m. CST on Tuesday, December 6, marked the last time this will happen on the Artemis I mission. This was less than a day after completing the return powered flyby burn that put the spacecraft on course for splashdown Sunday, December 11. Earth’s force of gravity is now the primary gravitational force acting on the spacecraft.

Genius Dog 336 x 280 - Animated

Orion successfully performed the fourth return trajectory correction burn at 4:43 a.m. using the reaction control system thrusters. The burn lasted 5.7 seconds and changed the velocity of the spacecraft by 0.6 feet per second.

Artemis I Flight Day 20 Pre-RPF Imagery

Solar array-mounted cameras capture close-up images of NASA s Orion Command Module and European Service Module on the 20th day of the Artemis I mission Windows on the Orion capsule offer a glimpse of Commander Moonikin Campos a manikin equipped with sensors measuring radiation acceleration and vibration data throughout the mission. Credit: NASA

Flight controllers used Orion’s cameras to inspect the crew module thermal protection system and European Service Module, the second of three planned external spacecraft inspections. Teams conducted this survey early in the mission to provide detailed images of the spacecraft’s external surfaces after it had flown through the portion of Earth’s orbit containing the majority of space debris, and teams reported no concerns after reviewing the imagery. This second inspection during the return phase is being used to assess the overall condition of the spacecraft several days before re-entry.

During both inspections, the Integrated Communications Officer, or INCO, commanded cameras on the four solar array wings to take a series of still images. Engineers and flight controllers at <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. Its vision is &quot;To discover and expand knowledge for the benefit of humanity.&quot; Its core values are &quot;safety, integrity, teamwork, excellence, and inclusion.&quot;

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>NASA’s Johnson Space Center in Houston will review the imagery over the coming days. A final photographic survey will be conducted Friday as Orion continues its journey home.

Orion Approaches Moon for Return Powered Flyby

A portion of the far side of the Moon looms large just beyond the Orion spacecraft in this image taken on the 20th day of the Artemis I mission by a camera on the tip of one of Orion’s solar arrays. The return powered flyby burn committed Orion to a return to Earth trajectory ahead of a splashdown off the coast of California on December 11. At its closest point, Orion flew within 80 miles of the lunar surface. Credit: NASA

Teams responsible for recovering Orion after its splashdown are continuing preparations ahead of the December 11 splashdown off the coast of California. The mission management team will determine the landing site location Thursday, December 8. Listen to NASA’s Artemis I recovery director, Melissa Jones, talk about what it takes to fetch the Orion spacecraft from the Pacific Ocean at the end of the mission on “Houston We Have a Podcast.”

Just after 5:30 p.m. on December 6, Orion was traveling 244,000 miles (393,000 km) from Earth and about 79,000 miles (127,000 lkm) from the Moon, cruising at 500 miles per hour (800 km per hour).

Adblock test (Why?)

Source link

Continue Reading