Sun is white and not yellow, confirms former NASA astronaut!


Most people believe the Sun is yellow since it appears yellow from the ground, but after reading this tweet, we may have to rethink our views.

This space truth was recently confirmed by NASA astronaut Scott Kelly in a widely shared tweet. The Sun's true colour is actually white, and the explanation the dwarf star typically seems yellow is due to an odd interaction between light physics that causes the sun to look yellow the majority of the time.

Our atmosphere causes the sun to appear yellow. But once you are outside of the atmosphere of the Earth, the Sun appears to be all white. NASA claims that this is because of way our eyes see colour.

Sunsets and sunrises seem red, yellow, or orange because the sun's light must traverse through all of Earth's atmosphere to reach the surface when it is lower in the sky than when it is directly overhead.

According to NASA, shorter light wavelengths, like blue, are more likely to be scattered through the atmosphere as time goes on, whereas longer light wavelengths, like red, can go considerably farther.

Since the amount of sunshine merely inundates the photoreceptor cells in our eyes, blending all the colours together, we are unable to distinguish a single colour from the sun. White is the result of combining all colours of light. As a result, the sun appears white in space and yellow on Earth. DailyBangladesh/RAH, Source: https://www.daily-bangladesh.com/
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A Blazar in the Early Universe: Details Revealed in Galaxy's Jet 12.8 Billion Light-Years from Earth

Credit: Spingola et al.; Bill Saxton, NRAO/AUI/NSF.

The supersharp radio "vision" of the National Science Foundation's Very Long Baseline Array (VLBA) has revealed previously unseen details in a jet of material ejected at three-quarters the speed of light from the core of a galaxy some 12.8 billion light-years from Earth. The galaxy, dubbed PSO J0309+27, is a blazar, with its jet pointed toward Earth, and is the brightest radio-emitting blazar yet seen at such a distance. It also is the second-brightest X-ray emitting blazar at such a distance. 

In this image, the brightest radio emission comes from the galaxy's core, at bottom right. The jet is propelled by the gravitational energy of a supermassive black hole at the core, and moves outward, toward the upper left. The jet seen here extends some 1,600 light-years, and shows structure within it.

At this distance, PSO J0309+27 is seen as it was when the universe was less than a billion years old, or just over 7 percent of its current age.

An international team of astronomers led by Cristiana Spingola of the University of Bologna in Italy, observed the galaxy in April and May of 2020. Their analysis of the object's properties provides support for some theoretical models for why blazars are rare in the early universe. The researchers reported their results in the journal Astronomy & Astrophysics.

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

Contacts and sources: 
Dave Finley
The National Radio Astronomy Observatory i

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Indian-American among 18 astronauts selected for NASA's manned Moon mission


DEC 11, 2020 WASHINGTON: An Indian-American is among the 18 astronauts selected by NASA for its manned mission to the Moon and beyond. NASA on Wednesday named the 18 astronauts -- half of them women -- who will train for its Artemis moon-landing programme. Raja Jon Vurputoor Chari, 43, a graduate of the US Air Force Academy, MIT, and US Naval Test Pilot School, is the only Indian-American in the list. He was selected by NASA to join the 2017 Astronaut Candidate Class. He reported for duty in August 2017 and having completed the initial astronaut candidate training is now eligible for a mission assignment. "My fellow Americans, I give you the heroes of the future who will carry us back to the Moon and beyond: the Artemis Generation," Vice President Mike Pence said at NASA''s Kennedy Space Centre in Florida on Wednesday. "It really is amazing to think that the next man and the first woman on the Moon are among the names that we just read...We started today reflecting on a great hero of the past. The Artemis Generation are the heroes of American space exploration in the future," Pence said after he introduced the members of the Artemis Team during the eighth National Space Council meeting. The astronauts on the Artemis Team come from a diverse range of backgrounds, expertise and experience. Most of the astronauts in the group are in their 30s or 40s. The oldest is 55, the youngest 32. The agency's modern lunar exploration programme will land the first woman and next man on the Moon in 2024 and establish a sustainable human lunar presence by the end of the decade, NASA said. NASA will announce flight assignments for astronauts later, pulling from the Artemis Team. Additional Artemis Team members, including international partner astronauts, will join this group, as needed. "We are incredibly grateful for the president and vice president's support of the Artemis program, as well as the bipartisan support for all of NASA's science, aeronautics research, technology development, and human exploration goals," said NASA Administrator Jim Bridenstine. "As a result, we're excited to share this next step in exploration - naming the Artemis Team of astronauts who will lead the way, which includes the first woman and next man to walk on the lunar surface," he added. The selected astronauts will help NASA prepare for the coming Artemis missions, which begin next year working with the agency's commercial partners as they develop human landing systems; assisting in the development of training; defining hardware requirements; and consulting on technical development. They also will engage the public and industry on NASA''s exploration plans. "There is so much exciting work ahead of us as we return to the moon, and it will take the entire astronaut corps to make that happen," Chief Astronaut Pat Forrester said. "Walking on the lunar surface would be a dream come true for any one of us, and any part we can play in making that happen is an honour," he said. The other members on the list include Christina Koch and Jessica Meir -- the two astronauts who performed the world''s first all-female spacewalk last year. Copyright © Jammu Links News, Source: Jammu Links News
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