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The oldest material on Earth has been found in a meteorite – CNN

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Our sun is around 4.6 billion years old, meaning this stardust existed long before our sun or solar system were even a reality. The stardust found on the meteorite are called presolar grains because they formed before our sun.
Stars are born when gas, dust and heat combine in just the right way. They can exist for millions or even billions of years before dying and expelling their key ingredients into space. This in turn helps new stars to be born, creating a space daisy chain.
Meteorites, if they don’t knock into too many things, can act like time capsules of the materials trapped within them, like stardust. That’s why the discovery of the presolar grains is such a rarity — only 5% of meteorites found on Earth contain them. Their impossibly tiny size is difficult to fathom.
Evidence of ancient meteorites found in Florida fossil clams
One hundred of the largest found presolar grains could fit on a period, according to a release by the Field Museum in Chicago.
A new study of presolar grains from the Murchison meteorite recovered in Australia published Monday in the Proceedings of the National Academy of Sciences journal.
“This is one of the most exciting studies I’ve worked on,” said Philipp Heck, lead study author and a curator at the Field Museum. “These are the oldest solid materials ever found, and they tell us about how stars formed in our galaxy. They’re solid samples of stars.”
A magnified view of a preosolar grain, or stardust. The grain is  about 8 micrometers.A magnified view of a preosolar grain, or stardust. The grain is  about 8 micrometers.
The meteorite was recovered in 1969 and presolar grains were isolated from it.
“It starts with crushing fragments of the meteorite down into a powder,” said Jennika Greer, study co-author and a graduate student at the Field Museum and the University of Chicago. “Once all the pieces are segregated, it’s a kind of paste, and it has a pungent characteristic. It smells like rotten peanut butter.”
Dissolving the paste in acid reveals the presolar grains, allowing the researchers to determine their age and the type of star they once belonged to.
The researchers were able to measure the exposure of the grains to cosmic rays, highly energized particles zipping through our galaxy.
Ice fossils found in 4.6 billion-year-old meteorite reveal building blocks of our solar systemIce fossils found in 4.6 billion-year-old meteorite reveal building blocks of our solar system
“Some of these cosmic rays interact with the matter and form new elements,” Heck said. “And the longer they get exposed, the more those elements form. I compare this with putting out a bucket in a rainstorm. Assuming the rainfall is constant, the amount of water that accumulates in the bucket tells you how long it was exposed.”
Many of the grains recovered were between 4.6 and 4.9 billion years old, while others were older than 5.5 billion years.
They also learned that seven billion years ago, more stars began forming.
“We have more young grains than we expected,” Heck said. “Our hypothesis is that the majority of those grains, which are 4.9 to 4.6 billion years old, formed in an episode of enhanced star formation. There was a time before the start of the solar system when more stars formed than normal.”
NASA has found sugar in meteorites that crashed to EarthNASA has found sugar in meteorites that crashed to Earth
Astronomers have argued about the rate of star formation. Some believe it’s steady and unchanging, while others believe there are peaks and dips.
“Some people think that the star formation rate of the galaxy is constant,” Heck said. “But thanks to these grains, we now have direct evidence for a period of enhanced star formation in our galaxy seven billion years ago with samples from meteorites. This is one of the key findings of our study.”
They also determined that the presolar grains have a habit of clumping together in granola-like clusters, which they didn’t think possible, Heck said.
Understanding the grains has shed light not only on stars and how long their stardust can last but also more on galaxies and their timelines.
“With this study, we have directly determined the lifetimes of stardust. We hope this will be picked up and studied so that people can use this as input for models of the whole galactic life cycle,” Heck said. “It’s so exciting to look at the history of our galaxy. Stardust is the oldest material to reach Earth, and from it, we can learn about our parent stars, the origin of the carbon in our bodies [and] the origin of the oxygen we breathe. With stardust, we can trace that material back to the time before the sun.”

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NASA satellite images reveal dramatic melting in Antarctica, Report – Tdnews

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NASA satellite images reveal dramatic melting in Antarctica, Report

NASA satellite pictures reveal the scale of “widespread melting” observed earlier this month. On February 6, weather station thermometers peaked at 18.3C (65F) degrees – about the same temperature as Los Angles, US, that day.

“I haven’t seen melt ponds develop this quickly in Antarctica. You see these kinds of melt events in Alaska and Greenland, but not usually in Antarctica,” said Mauri Pelto, a glaciologist at Nichols College, in a statement. Widespread surface melting was also observed by Pelto on the nearby Boydell Glacier.

Images taken by the Operational Land Imager (OLI) on Landsat 8 on February 4 and again nine days later show Eagle Island’s 1.5 square kilometers (nearly 1 square mile) of snowpack saturated with meltwater (blue circles below). Climate models suggest that the area saw a peak melt of 30 millimeters (1.2 inches) on February 6. In total, Eagle Island lost 106 millimeters (4.2 inches) of ice during the warm spell.

Rapid melting is caused by sustained high temperatures significantly above freezing, an anomaly that has become more common in recent years, according to NASA. A heat map taken using the Goddard Earth Observing System (GEOS) model also clocked record temperatures above 10°C (50°F) at 2 meters (about 6.5 feet) above the ground. High temperatures seen earlier this month are caused by a combination of meteorological events, including higher bouts of pressure centered over Cape Horn that allowed warmer temperatures to build while dry, warm foehn winds likely brought with them warmer air to the continent.

This month’s heatwave marks the third melt event of the Antarctic 2019-20 summer, following warm spells in November 2019 and January of this year.

“If you think about this one event in February, it isn’t that significant,” said Pelto. “It’s more significant that these events are coming more frequently.”

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46000-year-old Ice Age bird has been found in Siberian permafrost – The Weather Network

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Researchers are remarking at the newly discovered remains of an Ice Age bird that has been identified as a horned lark and is estimated to be 46,000-years-old.

A recently published study says that the bird was buried and frozen within the permafrost in near the village of Belaya Gora that is located in northeastern Siberia. The bird still had many of its feathers and the researchers state that it is “exceptionally well-preserved.”

Experts from the Swedish Museum of Natural History tested the bird’s feathers and say that there is a chance it could be an ancestor to two subspecies of lark that are alive today.

“This finding implies that the climatic changes that took place at the end of the last Ice Age led to the formation of new subspecies,” said Dr. Love Dalén during an interview with CNN.

frozen bird big
The bird carcass that was found in Siberian permafrost. Credit: Love Dalén

The study says that it is a significant finding for this body of research because it is a rare opportunity to learn more about past ecosystems and what the climatic conditions at that period of time were like. The researchers state that learning about this species habitat and their response to the changing climate will enable a better understanding of how species, populations, and communities could respond to present-day climate change.

Interestingly, the bird was found at the same site as an 18,000-year-old frozen puppy called “Dogor,” which researchers are still trying to determine if the specimen is a wolf or dog. The dog was found in nearly perfect condition within the permafrost and some scientists think that this could be the oldest dog ever found.

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New NASA Photos From Antarctica Reveal Shocking Levels of Ice Melt – ScienceAlert

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Antarctica is supposed to be an extremely cold place. The annual mean temperature of the snow-laden continent’s central area is -57 degrees Celsius (−70.6°F); even the coast averages around -10°C (14°F).

But on February 6, the weather station at Esperanza Base on the Antarctic Peninsula – the northernmost tip of the content – logged the hottest temperature ever recorded on the mainland, at 18.3°C (64.9°F).

It beat out the former record of 17.5°C, from 24 March 2015.

This latest heatwave lasted for about a week, and images of Eagle Island, taken by the Operational Land Imager on Landsat 8, have now captured a pretty depressing picture of its impact.

The tiny Eagle Island is located just off the coast of Graham Land in the Antarctic Peninsula. The record-high temperatures have resulted in a large amount of Eagle Island’s ice cap melting into the sea, while areas towards the middle of the island saw melt ponds form astonishingly quickly.

“I haven’t seen melt ponds develop this quickly in Antarctica,” says Mauri Pelto, a glaciologist at Nichols College.

“You see these kinds of melt events in Alaska and Greenland, but not usually in Antarctica.”

Pelto also notes that the source of this melt event – persistent high temperatures significantly above freezing – is not typical of Antarctic weather patterns. Nevertheless, these have become more common recently.  

In total, snow pack on Eagle Island had over 10 centimetres (4 inches) of melt in the span of just a few days – between February 6 and February 11.  

Air temperatures on February 9. (GEOS-5/NASA)

This isn’t even the first heatwave this season, but represents the third major melt event of the 2019-2020 Southern Hemisphere summer, with both November and January also suffering from exceptionally warm weather.

“If you think about this one event in February, it isn’t that significant,” said Pelto.

“It’s more significant that these events are coming more frequently.”

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