Glaciers In Greenland Are Melting Like Never Before, Especially The Helheim Glacier - News Neni - Canadanewsmedia
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Glaciers In Greenland Are Melting Like Never Before, Especially The Helheim Glacier – News Neni

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Helheim Glacier- is where Earth’s refrigerator door is left open, where glaciers dwindle, and seas start to rise.

Air and ocean scientist David Holland, who’s been monitoring Greenland from above and beneath, calls it “the end of the planet.” He’s referring to geography, not making an apocalyptic prediction. But in some ways, this spot just inside the Arctic Circle is where the planet’s hotter and watery future is being written.

It’s so warm right here that on an August day, coats are left on the ground and Holland and colleagues work on the thin melting ice without gloves. In one of many closest towns, Kulusuk, the morning temperature reached 52 degrees Fahrenheit — warm sufficient for shirtsleeves.

The ice Holland is standing on, is hundreds and thousands of years old. Scientists say it will likely be gone within a year or two, adding more water to rising seas worldwide.

Summer season this year is striking Greenland with record-shattering heat and extreme melt. By season’s end, about 440 billion tons of ice — perhaps more — could have melted or calved off Greenland’s giant ice sheet, experts estimate. That’s sufficient to flood all the state of Pennsylvania underwater a couple of foot deep.

Between July 31 and Aug. 3 alone, more than 58 billion tons melted from the surface. The average for this time of year is less than 18 billion tons. And that doesn’t even count the massive calving events or the nice and cozy water eating away at the glaciers from beneath.

One of the places hit hardest in this hot Greenland summertime is on the south-eastern fringe of the vast frozen island. Helheim, one of Greenland’s fastest-retreating glaciers, has shrunk about 6 miles since scientists came here in 2005.

Several scientists, such as oceanographer Josh Willis of NASA’s Jet Propulsion Laboratory, mentioned what’s occurring is the results of both human-made climate change and natural however bizarre climate patterns.

Glaciers right here do shrink in the summertime and grow in the winter, however nothing like this year.

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Elon Musk’s Starlink Satellites Are Already Causing a Headache for Astronomers – Gizmodo

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Several Starlink satellites in orbit, as seen above the Cerro Tololo Observatory in Chile on November 18.
Image: Clara Martínez-Vázquez, Cliff Johnson, CTIO/AURA/NSF

Astronomers at a Chilean observatory were rudely interrupted earlier this week when a SpaceX satellite train consisting of 60 Starlink satellites drifted overhead, in what scientists are apparently going to have to accept as the new normal.

Launched into orbit on November 11, the Starlink smallsat train took five minutes to pass over the Cerro Tololo Inter-American Observatory in Chile, according to a tweet from astronomer Clarae Martínez-Vázquez.

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“Wow!! I am in shock!!,” tweeted Martínez-Vázquez. “The huge amount of Starlink satellites crossed our skies tonight at [Cerro Tololo]. Our DECam [Dark Energy Camera] exposure was heavily affected by 19 of them!,” to which she added: “Rather depressing… This is not cool!”

Responding to this tweet, astronomer Cliff Johnson, a team member and a CIERA Postdoc Fellow in Astronomy at Northwestern, tweeted out a view of the disrupted data, showing an array of satellite trails strewn across an image of space.

The astronomers were collecting data using the DECam instrument, a high-performance, wide-field imager on the CTIO Blanco 4-meter telescope, as part of the DELVE survey, which is currently mapping the outer fringes of the Large and Small Magellanic Clouds as well as a significant fraction of the southern sky at optical wavelengths. Key goals of the project are to study the stellar halo around the Magellanic Clouds and detect new dwarf galaxies in orbit around the Clouds or the nearby Milky Way.

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The Starlink-tarnished DECam frame, showing satellite trails across the field of view.
Image: Clara Martínez-Vázquez, Cliff Johnson, CTIO/AURA/NSF

But this research was punctuated as the Starlink train passed overhead during the early morning of Monday, November 18.

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“In this case, 1 out of about 40 exposures we took during our half-night of observations was affected by the satellite trails,” Johnson told Gizmodo in an email. “And in the case of that single exposure, a maximum of 15 percent of the image was affected by the trails. Beyond the image itself, we also had to be careful as the trail-affected image also impacted our survey operations due to the large number of image artifacts biasing our quality-control measurements.”

Taken as a whole, however, “these numbers tend to show that the effect on our science was more on the annoyance level rather than total disruption,” he wrote. That said, “this may only be the beginning of problems for astronomers, so I believe the community reaction and alarm is warranted.” Should the proposed sizes of these satellite megaconstellations—which are projected to include upwards of tens of thousands of individual elements—actually be achieved, “that has the potential to significantly impact our observational data,” said Johnson.

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A similar thing happened earlier this year after the first batch of 60 Starlink satellites was delivered to orbit, with some people even believing they were UFOs. Alarmed by the inaugural batch of Starlink satellites, the U.S. American Astronomical Society issued a warning, saying megaconstellations could threaten scientific observations of space.

The train effect, in which the satellites are lined up neatly in a bright row, is a temporary one. Eventually, the smallsats disperse and enter into their own unique orbits in a process that takes a few weeks. That said, the number of objects in space—dispersed or not—is about to experience a dramatic uptick.

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As it stands, the impacts of these satellite trains “remain manageable” and the “worst effects temporary,” Johnson told Gizmodo.

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“I agree with the tone of the recent IAU statement that calls for immediate, meaningful discussion between regulators, satellite providers, and astronomers to highlight ways that impacts to astronomy can be minimized—and not just optical, but radio astronomy as well—and rule out the worst-case scenarios of unlimited launches and unchecked deployments,” Johnson told Gizmodo.

In response to these concerns, SpaceX has said it is taking steps to color the base of Starlink satellites black, in order to minimize their brightness. Experts aren’t convinced that’ll work, as some observatories use super-sensitive instruments to detect even the faintest objects.

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Scientists will likely have to get used to these sorts of disruptions, as regulating bodies aren’t lending a sympathetic ear. SpaceX has already received approval from the U.S. Federal Communications Commission (FCC) to launch 12,000 Starlink smallsats, and in October, the Elon Musk-led private space firm asked the FCC for permission to launch an additional 30,000 satellites on top of that by the mid 2020s. These satellite trains, along with their associated megaconstellations, will soon become a regular fixture of the night sky—and that doesn’t include constellations that are set to be built by SpaceX’s competitors, including networks proposed by OneWeb, Telsat, and Amazon.

With the starry night already obscured by light pollution from our cities, it seems an unhindered view into space may soon elude astronomers as well.

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Photos Show Evidence of Life on Mars, Claims Scientist – NDTV

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As scientists scramble to determine whether there is life on Mars, a researcher from Ohio University in US believes that there is evidence of insect-like creatures on the red planet.

Courtesy photographs from various Mars rovers, Professor Emeritus William Romoser’s research found numerous examples of insect-like forms, structured similarly to bees, as well as reptile-like forms, both as fossils and living creatures.

“There has been and still is life on Mars,” Romoser said, noting that the images appear to show both fossilised and living creatures.

“There is apparent diversity among the Martian insect-like fauna which display many features similar to Terran insects that are interpreted as advanced groups – for example, the presence of wings, wing flexion, agile gliding/flight, and variously structured leg elements,” Romoser added.

Romoser said that while the Martian rovers, particularly the Curiosity Rover, have been looking for indicators of organic activity, there are a number of photos which clearly depict the insect- and reptile-like forms.

Photo Credit: Ohio University

Numerous photos show images where arthropod body segments, along with legs, antennae and wings, can be picked out from the surrounding area, and one even appears to show one of the insects in a steep dive before pulling up just before hitting the ground.

Individual images were carefully studied while varying photographic parameters such as brightness, contrast, saturation, inversion, and so on. No content was added, or removed.

Criteria used in Romoser’s research included: Dramatic departure from the surroundings, clarity of form, body symmetry, segmentation of body parts, repeating form, skeletal remains, and observation of forms in close proximity to one another.

Particular postures, evidence of motion, flight, apparent interaction as suggested by relative positions, and shiny eyes were taken to be consistent with the presence of living forms.

“Once a clear image of a given form was identified and described, it was useful in facilitating recognition of other less clear, but none-the-less valid, images of the same basic form,” Romoser said. “

An exoskeleton and jointed appendages are sufficient to establish identification as an arthropod.

Three body regions, a single pair of antennae, and six legs are traditionally sufficient to establish identification as ‘insect’ on Earth.

These characteristics should likewise be valid to identify an organism on Mars as insect-like. On these bases, arthropodan, insect-like forms can be seen in the Mars rover photos.”

These creatures loosely resemble bumble bees or carpenter bees on Earth. Other images show these “bees” appearing to shelter or nest in caves. And others show a fossilized creature that resembles a snake.

“The presence of higher metazoan organisms on Mars implies the presence of nutrient/energy sources and processes, food chains and webs, and water as elements functioning in a viable, if extreme, ecological setting sufficient to sustain life,” Romoser said.

“The evidence of life on Mars presented here provides a strong basis for many additional important biological as well as social and political questions,” he added.

The study was presented at Entomological Society of America national meeting.

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Starlink Satellites Posing Issues For Astronomers – Hackaday

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Spotting satellites from the ground is a popular pastime among amateur astronomers. Typically, the ISS and Iridium satellites have been common sightings, with their orbits and design causing them to appear sufficiently bright in the sky. More recently, SpaceX’s mass launches of Starlink satellites have been drawing attention for the wrong reasons.

A capture from the Cerro Telolo observatory, showing the many Starlink satellite tracks spoiling the exposure.

Starlink is a project run by SpaceX to provide internet via satellite, using a variety of techniques to keep latency down and bandwidth high. There’s talk of inter-satellite laser communications, autonomous obstacle avoidance, and special designs to limit the amount of space junk created. We’ve covered the technology in a comprehensive post earlier this year.

The Starlink craft have long worried astronomers, who rely on a dark and unobstructed view of the sky to carry out their work. There are now large numbers of the satellites in relatively low orbits, and the craft have a high albedo, meaning they reflect a significant amount of the sunlight that hits them. With the craft also launching in a closely-packed train formation, there have already been impacts on research operations.

There is some hope that as the craft move to higher orbits when they enter service, this problem will be reduced. SpaceX are also reportedly considering modifications to the design to reduce albedo, helping to keep the astronomy community onside. Regardless, with plans on the table to launch anywhere from 12,000 to 42,000 satellites, it’s likely this isn’t the last we’ll hear about the issue.

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