Connect with us

Science

Researchers developed a technique to predict space radiation exposure for future missions – Tech Explorist

Published

 on


For discoveries, astronauts traveling to the moon, Mars, and other space destinations are exposed to space radiation risk. To reduce and predict spaceflight hazards and protect astronauts from space radiation, NASA is using the International space station to predict space radiation exposure for future exploration missions.

The study is published in the Journal Nature-scientific Reports on results from the ISS Medical Monitoring study of International Space Station Astronauts. This study demonstrates the sensitivity of an individual astronaut’s DNA to radiation exposure on Earth to predict their DNA’s response during spaceflight by measuring changes to their chromosomes.

“We wanted to know if it is possible to detect and measure radiation exposure damage in the bodies of astronauts, and if there were differences based on age, sex, and other factors that could be measured before they go into space,” said senior scientist Honglu Wu from NASA’s Johnson Space Center in Houston. “We hope to use these measurements to help develop and compare methods of protecting astronauts from radiation.”

One of the three primary sources of space radiation is particles trapped in Earth’s magnetic field. The other two are particles shot into space during solar flares and galactic cosmic rays originating outside our solar system.

Various adverse effects on health due to radiation exposure include cancer risk, alterations to the central nervous system, other cardiovascular disorders, and adverse health effects.

We are safe on Earth from radiation because of Earth’s magnetic field and planet’s atmosphere.

On missions on lower earth orbit, astronauts are protected from some space radiation exposure by combining Earth’s magnetic field, spacecraft shielding, and limiting the astronaut’s time in space.

Space radiation is made up of protons and all the elements on the periodic table. It enters the human body at energies approaching the speed of light and can damage DNA.
Credits: NASA

NASA’s Human Research Program seeks to conduct research in the field of medical countermeasures such as pharmaceuticals and early disease detection technology to help mitigate the consequences of space radiation exposure, especially for more extended missions. An important part of this is figuring out ways to estimate the sensitivity of astronauts to radiation prior to the flight and continually assess long-term health for the remainder of their lifetimes.

During exploration missions beyond Earth’s orbit, it may not be possible to provide the same level of protection from shielding or limit mission exposure time.

Chromosomes accumulate alterations with age resulting from normal bodily processes or exposure to environmental factors. Alterations to Chromosomes, which contain DNA building blocks of human bodies, can increase the risk of cancer and other diseases.

During the ISS Medical Monitoring experiment, researchers studied blood samples from 43 space station crew members to measure their levels of chromosome alterations from radiation and other factors before and after a mission. These alterations to chromosomes are observed in a very small percentage of individual cells within a person’s blood.

The study involved three key measurements. Before astronauts flew to the station, researchers examined their blood cells to assess their baseline chromosomal status against which any future alterations could be measured. Next, these blood samples were intentionally exposed to gamma-ray radiation on Earth to measure how easily their cells accumulated chromosomal changes. This measurement established each astronaut’s inherent sensitivity to radiation. Finally, after the astronauts returned from their missions, the study team again took blood samples from the individuals to assess their level of chromosomal alterations.

Blood samples taken by former NASA astronaut Chris Cassidy before aboard the International Space Station. Samples like these were taken before and after astronaut’s missions to space to measure radiation damage of astronauts in space.
Credits: NASA

Wu and retired NASA statistician Alan Feiveson then compared each astronaut’s levels of post-flight alterations to their corresponding background levels established before launching into space. In addition, the investigators checked to see if any of this increase could also be explained by age, sex, or individual sensitivity.

“It was an intriguing challenge to develop a statistical method for analyzing all of the blood samples to see if an astronaut’s pre-flight levels of radiosensitivity actually plays a role in predicting their spaceflight-induced chromosome alterations,” said Feiveson

“The findings suggest that if older astronauts indeed have higher sensitivities to radiation, they might be at higher risk of chromosome alterations,” said Wu. “While experiencing chromosome alterations does not automatically mean someone will develop cancer, it does raise the question of whether they are at increased risk for it.”

Younger astronauts are thought to be more susceptible than older astronauts to the long-term health consequences resulting from space radiation exposure. This is partly because younger astronauts have more lifespan remaining and could live long enough to develop cancer from the radiation exposure; it usually takes five to 20 years or more after the radiation exposure for cancer to occur.

“When thinking about going to Mars, we typically have thought it might be better to send older astronauts because of their experience and lower risk of developing cancer in their lifetime,” said Wu. “Now, based on this new research, we know that we should study the age effects of radiation exposure more.”

Journal Reference
  1. Feiveson, A., George, K., Shavers, M. et al. Predicting chromosome damage in astronauts participating in international space station missions. Sci Rep 11, 5293 (2021). DOI: 10.1038/s41598-021-84242-5

Adblock test (Why?)



Source link

Continue Reading

Science

Bird reports rose during lockdowns | Cornell Chronicle – Cornell Chronicle

Published

 on


Around 80% of bird species examined in a new study were reported in greater numbers in human-altered habitats during pandemic lockdowns, according to new research based on data from the eBird program at the Cornell Lab of Ornithology.

In the paper, “Reduced Human Activity During COVID-19 Alters Avian Land Use Across North America,” published Sept. 22 in Science Advances, researchers compared online eBird observations from the United States and Canada from before and during the pandemic. They focused on areas within about 100 km of urban areas, major roads, and airports.

Vast amounts of data from a likewise vast geographic area were vital for this study. The researchers used more than 4 million eBird observations of 82 bird species from across Canada and the U.S.

“A lot of species we really care about became more abundant in human landscapes during the pandemic,” said study senior author Nicola Koper of the University of Manitoba, which led the research. “I was blown away by how many species were affected by decreased traffic and activity during lockdowns.”

Reports of bald eagles increased in cities with the strongest lockdowns. Ruby-throated hummingbirds were three times more likely to be reported within a kilometer of airports than before the pandemic. Barn swallows, a threatened species in Canada, were reported more often within a kilometer of roads than before the pandemic.

A few species decreased their use of human-altered habitat during the pandemic. Red-tailed hawk reports decreased near roads, perhaps because there was less roadkill when traffic declined. But far more species had increased counts in these human-dominated landscapes.

The authors filtered pandemic and pre-pandemic eBird reports so that the final data sets had the same characteristics, such as location, number of lists, and level of birdwatcher effort.

“We also needed to be aware of the detectability issue,” said co-author Alison Johnston, assistant director of the Center for Avian Population Studies and Ecological Data in the Lab of Ornithology. “Were species being reported in higher numbers because people could finally hear the birds without all the traffic noise, or was there a real ecological change in the numbers of birds present?”

The study tested whether better detectability might be a factor in the larger bird numbers reported. If it was, the scientists expected that to be more noticeable for smaller birds, which are harder to detect beneath traffic noise. However, effects were noticed across many species, from hawks to hummingbirds, suggesting that the increased numbers were not only caused by increased detectability in the quieter environments.

“Having so many people in North America and around the world paying attention to nature has been crucial to understanding how wildlife react to our presence,” says lead author Michael Schrimpf, a postdoctoral fellow at the University of Manitoba. “Studies such as this one rely on volunteer birdwatchers, so if you enjoy watching wildlife, there are many projects out there, like eBird and iNaturalist, that can use your help.”

The study was funded by Natural Sciences and Engineering Research Council of Canada with in-kind support provided by Environment and Climate Change Canada and the Cornell Lab of Ornithology.

Adblock test (Why?)



Source link

Continue Reading

Science

SpaceX Crew Dragon cupola provides awe-inspiring view of the Earth from space – Californianewstimes.com

Published

 on


Holy Molly.

SpaceX

Give a few seconds (or a minute or two if needed) to startle and gaze at the Earth’s scenery from the recently launched SpaceX Crew Dragon above.

on Wednesday, As part of the Inspiration4 mission, four civilians were blown up in a three-day orbital stay.Tied to the SpaceX Crew Dragon with one of the upgrades: Cupola. The transparent dome at the top of the Dragon Capsule provides the Inspiration 4 crew with the best views of the Earth that up-and-coming astronauts can dream of. This is the first time a cupola has been installed on a dragon. Dragons typically carry astronauts and cargo to the ISS, with docking ports at the top instead of windows.

A short video posted to the SpaceX Twitter account hours after the launch shows the cupola’s transparent dome against the Earth, which is a pale blue marble.

As the Crew Dragon orbits from a height of 585 kilometers (more than 360 miles), our planet is exposed to the sun and slowly roams around the orbs.

Inspiration 4’s crew (commander Jared Isaacman, doctor’s assistant, childhood cancer survivor Haley Arseno, aerospace engineer Chris Sembroski, African-American geology professor Sian Proctor) are in orbit for three days. Ride and stare at the cupola and the earth.

And did you say that the cupola is right next to the dragon’s toilet? Yeah, the view of the earth should be visible from the crew dragon’s bathroom. Isaacman told insiders Toilets are one of the few places where you can separate yourself from others with privacy curtains and have the best toilet windows of mankind. “When people inevitably have to use the bathroom, they will see one view of hell,” he said.

Astronauts who have been to space often talk about a phenomenon called the “overview effect.” Looking at the planet from above, the idea is that the way we think about the planet and the mass of humankind that depends on it will change. There may be a lot of revelation at the end of the Inspiration 4 journey, as I don’t know if they thought of it while sitting in the can.

The mission is the first mission to take off from the Florida coast on Wednesday night and be launched with four civilians. It is expected to return to Earth on Saturday and land in the Atlantic Ocean.

SpaceX Crew Dragon cupola provides awe-inspiring view of the Earth from space Source link SpaceX Crew Dragon cupola provides awe-inspiring view of the Earth from space

Adblock test (Why?)



Source link

Continue Reading

Science

Oldest human footprints in North America found in New Mexico – Al Jazeera English

Published

 on


Fossilised footprints dating 23,000 years push back the known date the continent was colonised by thousands of years.

Footprints dating back 23,000 years have been discovered in the United States, suggesting humans settled North America long before the end of the last Ice Age, according to researchers.

The findings announced on Thursday push back the date at which the continent was colonised by its first inhabitants by thousands of years.

The footprints were left in mud on the banks of a long-since dried up lake, which is now part of a New Mexico desert.

Sediment filled the indentations and hardened into rock, protecting evidence of our ancient relatives, and giving scientists a detailed insight into their lives.

The first footprints were found in a dry lake bed in White Sands National Park in 2009. Scientists at the United States Geological Survey recently analysed seeds stuck in the footprints to determine their approximate age, ranging from 22,800 to 21,130 years ago.

“Many tracks appear to be those of teenagers and children; large adult footprints are less frequent,” write the authors of the study published in the American journal Science.

“One hypothesis for this is the division of labour, in which adults are involved in skilled tasks whereas ‘fetching and carrying’ are delegated to teenagers.

“Children accompany the teenagers, and collectively they leave a higher number of footprints.”

Researchers also found tracks left by mammoths, prehistoric wolves, and even giant sloths, which appear to have been approximately at the same time as the humans visited the lake.

Historic findings

The Americas were the last continent to be reached by humanity.

For decades, the most commonly accepted theory has been that settlers came to North America from eastern Siberia across a land bridge – the present-day Bering Strait.

From Alaska, they headed south to kinder climes.

Archaeological evidence, including spearheads used to kill mammoths, has long suggested a 13,500-year-old settlement associated with so-called Clovis culture – named after a town in New Mexico.

This was considered the continent’s first civilisation, and the forerunner of groups that became known as Native Americans.

However, the notion of Clovis culture has been challenged over the past 20 years, with new discoveries that have pushed back the age of the first settlements.

Generally, even this pushed-back estimate of the age of the first settlements had not been more than 16,000 years, after the end of the so-called “last glacial maximum” – the period when ice sheets were at their most widespread.

This episode, which lasted until about 20,000 years ago, is crucial because it is believed that with ice covering much of the northern parts of the continent, human migration from Asia into North America and beyond would have been very difficult.

Adblock test (Why?)



Source link

Continue Reading

Trending