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They found two new craters on the moon and discovered a new mystery – Kathimerini English Edition

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After months of scrutinizing photographs of the lunar surface, scientists have finally found the crash site of a forgotten rocket stage that struck the far side of the moon in March.

They still do not know for sure which rocket the wayward debris originated from. And they are perplexed about why the impact excavated two craters and not just one.

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“It’s cool, because it’s an unexpected outcome,” said Mark Robinson, a professor of geological sciences at Arizona State University who serves as the principal investigator for the camera aboard NASA’s Lunar Reconnaissance Orbiter, which has been photographing the moon since 2009. “That’s always way more fun than if the prediction of the crater, its depth and diameter, had been exactly right.”

Robinson reported the discovery Friday on the website that stores images taken by the lunar orbiter.

The rocket crash intrigue started in January when Bill Gray, developer of Project Pluto, a suite of astronomical software used in calculating the orbits of asteroids and comets, tracked what looked like the discarded upper stage of a rocket. He realized it was on a collision course with the far side of the moon.

The crash was certain, at about 7:25 a.m. Eastern time on March 4. But the exact orbit of the object was not known, so there was some uncertainty about the time and place of the impact.

Gray said the rocket part was the second stage of a SpaceX Falcon 9 that launched the Deep Space Climate Observatory, or DSCOVR, for the National Oceanic and Atmospheric Administration in February 2015.

He was wrong.

A NASA engineer pointed out that the launch trajectory of DSCOVR was incompatible with the orbit of the object Gray was tracking. After some more digging, Gray concluded that the most likely candidate was a Long March 3C rocket that was launched from China a few months earlier, on Oct. 23, 2014.

Students at the University of Arizona reported that an analysis of the light reflected from the object found that the mix of wavelengths matched similar Chinese rockets rather than a Falcon 9.

But a Chinese official denied it was part of a Chinese rocket, saying that the rocket stage from that mission, which launched the Chang’e-5 T1 spacecraft, had reentered Earth’s atmosphere and burned up.

Regardless of what rocket it was part of, the object continued to follow the spiraling path dictated by gravity. At the predicted time, it slammed into the far side of the moon within the 350-mile-wide Hertzsprung Crater, out of sight of anyone on Earth.

The Lunar Reconnaissance Orbiter was not in a position to watch the impact, but the hope was that a freshly carved crater would show up in a photograph that the spacecraft took later.

Gray’s software made one prediction of the impact site. Experts at NASA’s Jet Propulsion Laboratory calculated a location a few miles to the east, while members of the Massachusetts Institute of Technology’s Lincoln Laboratory expected that the crash would occur tens of miles to the west.

That meant the researchers had to search a swath about 50 miles long for a crater a few tens of feet wide, comparing the lunar landscape before and after the crash to identify recent disturbances.

Robinson said he worried that “it was going to take us a year of imaging to fill in the box.”

While the Lunar Reconnaissance Orbiter has photographed the vast majority of the moon several times over the past 13 years, there are spots it has missed. It turned out that some of the gaps were near the expected crash site.

Robinson remembered thinking of Murphy’s Law and joking, “I know exactly where it’s going to hit.”

Because the crash was predicted a month ahead of time, the mission team was able to fill in most of the gaps.

Then the search started.

Usually, a computer program does the comparison, but that works best if the before-and-after pictures are taken at the same time of day. For this search, many of the images were taken at different times, and the difference in shadows confused the algorithm.

With all the false positives, “we just sat down and had several people manually going through the millions of pixels,” Robinson said.

Alexander Sonke, a senior in Arizona State’s geological sciences department, contributed to the effort. He estimated that he had spent about 50 hours over several weeks performing the tedious task.

Sonke graduated in May. He got married. He went on his honeymoon. A week and a half ago was his first day back at work — he is about to embark on his graduate school studies with Robinson as his adviser — and he resumed the search for the impact site.

He found it.

Sonke said he had seen “a group of pixels that looked significantly different in brightness” as the before-and-after images blinked back and forth.

“I was pretty confident when I saw it that this was a new geologic feature,” Sonke said. “I certainly jumped out of my seat a little, had a feeling that this was definitely it, and then tried to kind of restrain my excitement.”

The eastern crater, about 20 yards in diameter, is superimposed on the slightly smaller western one, which most likely formed a few thousandths of a second before the eastern one, Robinson said.

This is not the first time a spacecraft part has hit the moon. For example, pieces of the Saturn 5 rockets that took astronauts to the moon in the 1970s also carved craters. But none of those impacts created a double crater.

The reason this one did might point to its mystery identity. The October 2014 Chinese mission carried the Chang’e-5 T1 spacecraft, a precursor for another mission, Chang’e-5, which landed on the moon and brought rock samples back to Earth.

The precursor T1 spacecraft did not include a lander, but Robinson surmises that it had a heavy mass at the top of the stage to simulate the presence of one. If so, then rocket engines at the bottom and the lander simulator at the top could have created the two craters.

“That’s sheer speculation on my part,” Robinson said.

The other parts of the rocket stage would have been thin, light aluminum, not likely to make much of a dent on the lunar surface.

The actual impact site lay between the sites predicted by Gray and the NASA Jet Propulsion Laboratory, close to the NASA one. “It was within the margins of error that we had computed,” Gray said.

It was also fortunate that the Lunar Reconnaissance Orbiter team had filled in the gaps — called gores, in the language of mapmakers — in the images. “As Murphy would have it, that thing impacted in what was one of the gores,” Robinson said. “If I hadn’t been alerted, we wouldn’t have had a before image.”

The scientists might eventually have found the crash site. Dirt tossed out from a gouged crater is usually brighter, growing darker over time. That is how scientists identified the craters caused by Saturn 5 stages.

But they would still be looking for one small bright spot in the haystack of the moon.


This article originally appeared in The New York Times.

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Solar eclipse April 8 – South Grey News

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March 28, 2024

Graphic: Appalachian Mtn Club

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Grey Bruce Public Health is urging residents to resist the temptation to look directly at the sun during the upcoming solar eclipse and take steps to safeguard their visual health during this relatively rare celestial event.

On April 8, 2024, parts of southern and eastern Ontario will experience a total solar eclipse for the first time since 1925. Grey-Bruce will be outside of the so-called Path of Totality — a narrow area where the moon will completely block out the sun — but will still experience a partial eclipse.

The eclipse is expected to begin at about 2 pm and continue until 4:30 pm The eclipse will peak around 3:20 pm.

It is never safe to stare directly at the sun, but it may be tempting to do so during a solar eclipse.

Looking directly at the sun during an eclipse can cause retinal burns, blurred vision, and/or temporary or permanent loss of visual function, according to the Ontario Association of Optometrists. Damage to the eyes can occur without any sensation of pain.

Grey Bruce Public Health advises the following:

  • Do not look directly at the sun without proper eye protection during the solar eclipse. Looking at even a small sliver of the sun before or after the eclipse without proper eye protection can harm vision.
  • Keep a close eye on children and other vulnerable family members during the eclipse to ensure they do not inadvertently look up at the sun without proper eye protection.
  • To safely view the eclipse, ISO-certified eclipse glasses that meet the ISO 12312-2 international safety standard must be worn. Ensure these glasses are in good condition, without any wrinkles or scratches, and that they fully cover the entire field of vision. Put on the glasses when looking away from the sun, then look at the eclipse. Look away from the sun before taking the glasses off.
  • Regular sunglasses or homemade filters will not protect the eyes.
  • It is not safe to view the eclipse through a camera/phone lens, telescope, binoculars, or any other optical device.

Other ways to safely experience the solar eclipse include watching a livestream of the event or creating and using an eclipse box or pinhole projector.

Anyone experiencing temporary vision loss or blurred vision during or after the eclipse should speak with their eye care professional or healthcare provider as soon as possible.

Anyone experiencing blindness (immediate or delayed) after viewing the eclipse must seek emergency care immediately.

More information on the upcoming eclipse is available on the GBPH website.


At South Grey News, we endeavour to bring you truthful and factual, up-to-date local community news in a quick and easy-to-digest format that’s free of political bias. We believe this service is more important today than ever before, as social media has given rise to misinformation, largely unchecked by big corporations who put profits ahead of their responsibilities.

South Grey News does not have the resources of a big corporation. We are a small, locally owned-and-operated organization. Research, analysis and physical attendance at public meetings and community events requires considerable effort. But contributions from readers and advertisers, however big or small, go a long way to helping us deliver positive, open and honest journalism for this community.

Please consider supporting South Grey News with a donation in lieu of a subscription fee and let us know that our efforts are appreciated. Thank you.

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NASA to launch sounding rockets into moon's shadow during solar eclipse – Phys.org

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This photo shows the three APEP sounding rockets and the support team after successful assembly. The team lead, Aroh Barjatya, is at the top center, standing next to the guardrails on the second floor. Credit: NASA/Berit Bland

NASA will launch three sounding rockets during the total solar eclipse on April 8, 2024, to study how Earth’s upper atmosphere is affected when sunlight momentarily dims over a portion of the planet.

The Atmospheric Perturbations around Eclipse Path (APEP) sounding rockets will launch from NASA’s Wallops Flight Facility in Virginia to study the disturbances in the created when the moon eclipses the sun. The sounding rockets had been previously launched and successfully recovered from White Sands Test Facility in New Mexico, during the October 2023 .

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They have been refurbished with new instrumentation and will be relaunched in April 2024. The mission is led by Aroh Barjatya, a professor of engineering physics at Embry-Riddle Aeronautical University in Florida, where he directs the Space and Atmospheric Instrumentation Lab.

The sounding rockets will launch at three different times: 45 minutes before, during, and 45 minutes after the peak local eclipse. These intervals are important to collect data on how the sun’s sudden disappearance affects the ionosphere, creating disturbances that have the potential to interfere with our communications.

The ionosphere is a region of Earth’s atmosphere that is between 55 to 310 miles (90 to 500 kilometers) above the ground. “It’s an electrified region that reflects and refracts and also impacts as the signals pass through,” said Barjatya. “Understanding the ionosphere and developing models to help us predict disturbances is crucial to making sure our increasingly communication-dependent world operates smoothly.”

A sounding rocket is able to carry science instruments between 30 and 300 miles above Earth’s surface. These altitudes are typically too high for science balloons and too low for satellites to access safely, making sounding rockets the only platforms that can carry out direct measurements in these regions. Credit: NASA’s Goddard Space Flight Center

The ionosphere forms the boundary between Earth’s lower atmosphere—where we live and breathe—and the vacuum of space. It is made up of a sea of particles that become ionized, or electrically charged, from the sun’s energy or .

When night falls, the ionosphere thins out as previously ionized particles relax and recombine back into neutral particles. However, Earth’s terrestrial weather and space weather can impact these particles, making it a dynamic region and difficult to know what the ionosphere will be like at a given time.

It’s often difficult to study short-term changes in the ionosphere during an eclipse with satellites because they may not be at the right place or time to cross the eclipse path. Since the exact date and times of the are known, NASA can launch targeted sounding rockets to study the effects of the eclipse at the right time and at all altitudes of the ionosphere.

As the eclipse shadow races through the atmosphere, it creates a rapid, localized sunset that triggers large-scale atmospheric waves and small-scale disturbances or perturbations. These perturbations affect different radio communication frequencies. Gathering the data on these perturbations will help scientists validate and improve current models that help predict potential disturbances to our communications, especially high-frequency communication.

This conceptual animation is an example of what observers might expect to see during a total solar eclipse, like the one happening over the United States on April 8, 2024. Credit: NASA’s Scientific Visualization Studio

The APEP rockets are expected to reach a maximum altitude of 260 miles (420 kilometers). Each rocket will measure charged and neutral particle density and surrounding electric and magnetic fields. “Each rocket will eject four secondary instruments the size of a two-liter soda bottle that also measure the same data points, so it’s similar to results from fifteen rockets while only launching three,” explained Barjatya. Embry-Riddle built three secondary instruments on each rocket, and the fourth one was built at Dartmouth College in New Hampshire.

In addition to the rockets, several teams across the U.S. will also be taking measurements of the ionosphere by various means. A team of students from Embry-Riddle will deploy a series of high-altitude balloons. Co-investigators from the Massachusetts Institute of Technology’s Haystack Observatory in Massachusetts and the Air Force Research Laboratory in New Mexico will operate a variety of ground-based radars taking measurements.

Using this data, a team of scientists from Embry-Riddle and Johns Hopkins University Applied Physics Laboratory are refining existing models. Together, these various investigations will help provide the puzzle pieces needed to see the bigger picture of ionospheric dynamics.

The animation depicts the waves created by ionized particles during the 2017 total solar eclipse. Credit: MIT Haystack Observatory/Shun-rong Zhang. Zhang, S.-R., Erickson, P. J., Goncharenko, L. P., Coster, A. J., Rideout, W. & Vierinen, J. (2017). Ionospheric Bow Waves and Perturbations Induced by the 21 August 2017 Solar Eclipse. Geophysical Research Letters, 44(24), 12,067-12,073. https://doi.org/10.1002/2017GL076054

When the APEP- launched during the 2023 annular solar eclipse, scientists saw a sharp reduction in the density of charged particles as the annular eclipse shadow passed over the atmosphere.

“We saw the perturbations capable of affecting radio communications in the second and third rockets, but not during the first rocket that was before peak local eclipse,” said Barjatya. “We are super excited to relaunch them during the total eclipse to see if the perturbations start at the same altitude and if their magnitude and scale remain the same.”

The next total solar eclipse over the contiguous U.S. is not until 2044, so these experiments are a rare opportunity for scientists to collect crucial data.

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Royal Sask. Museum research finds insect changes may have set stage for dinosaurs' extinction – CTV News Regina

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Research by the Royal Saskatchewan Museum (RSM) shows that ecological changes were occurring in insects at least a million years before dinosaur extinction.

Papers published in the scientific journal, Current Biology, describe the first insect fossils found in amber from Saskatchewan and the unearthing of three new ant species from an amber deposit in North Carolina, according to a release from the province.

The amber deposit from in the Big Muddy Badlands of Saskatchewan, which was formed about 67 million years ago, preserved insects that lived in a swampy redwood forest about one million years before the extinction of dinosaurs.

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“Fossils in the amber deposit seem to show that common Cretaceous insects may have been replaced on the landscape by their more modern relatives, particularly in groups such as ants, before the extinction event,” Elyssa Loewen, curatorial assistant, said.

The research team was led by Loewen and Dr. Ryan McKellar, the RSM’s curator of paleontology.

“These new fossil records are closer than anyone has gotten to sampling a diverse set of insects near the extinction event, and they help researchers fill in a 17-million-year gap in the fossil record of insects around that time,” Dr. McKellar said.

The three ant species discovered in North Carolina also belonged to extinct groups that didn’t survive past the Cretaceous period.

“When combined with the work in Saskatchewan, the two recent papers show that there was a dramatic change in ant diversity sometime between 77 and 67 million years ago,” Dr. McKellar said in the release.

“Our analyses of body shapes in the fossils suggests that the turnover was not related to major differences in ecology, but it may have been related to something like the size and complexity of ant colonies. More work is needed to confirm this.”

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