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Yellowknifers bear witness to atypical meteors, and a scientist provides some context

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The Geminids meteor shower — caused by the extinct comet 3200 Phaethon and first detected by NASA in 1983 — was visible from the Ingraham Trail alongside the Northern lights on the evening of Dec. 14.

The Geminids meteor shower was forecasted to occur from Dec. 4 to 16, peaking the night of Dec. 13 and the morning of Dec. 14, according to the Old Farmer’s Almanac. This peak is when the most meteors were expected to fall per hour.

The almanac also states that meteors occur when the Earth passes through a stream of dust and debris left behind by a passing comet. When these bits strike the Earth’s upper atmosphere, friction with the air heats the particles and causes them to burn up. The Geminids appear brighter than most meteors because the outer layer of the extinct comet is completely gone, and its debris is mostly rocky material, which takes longer to burn up as they fall into the atmosphere. Most meteors are caused by the softer, icier debris from comets.

Also making the Geminids meteor shower unique is that the celestial objects move more slowly than other meteors, such as the Perseids, which is another meteor shower that takes place in August. The slower speed makes it easier to see the Geminids meteor shower.

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Also according to the Old Farmer’s Almanac, the Geminids were first observed in 1862 in Manchester, England. All other major meteor showers have been observed for centuries, making the Geminids meteor shower relatively new, comparatively speaking.

The Geminids meteors are visible all night long, and appear to fall away from the constellation Gemini.

The streaks of lights in the photographs are believed to be meteor trails below the aurora, according to William Archer, a program scientist working in solar-terrestrial sciences for the Canadian Space Agency.

The meteor trails were mostly white with trace colours in them. Archer said that the meteors travel fast enough that when they hit the dense portion of the Earth’s atmosphere and break up, both the atoms in the atmosphere and the meteor are excited, giving off light. Because the meteors can be made of many different elements, they give off different colours of light when they break up in our atmosphere, causing the meteor trails to have colour in them.

They formed mostly straight lines that stretched long across the sky, appearing underneath the Northern lights. Archer said the bottom edge of green aurora goes down to roughly 100 kilometers from the Earth, whereas the glow from a meteor trail occurs between 80 km and 120 km in altitude, relative to the Earth. The meteor trails would appear anywhere from a 10-second period to more than a minute. There were multiple appearances of the trails over the course of 30 minutes. Archer said the duration of the meteor trails were not typical, but some scientific studies observed a visible signature from meteor trails lasting for 30 minutes, citing a study from Sci-Hub.

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An asteroid will whip by Earth tomorrow in one of closest approaches ever recorded

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An asteroid the size of a delivery truck will whip past Earth on Thursday night, one of the closest such encounters ever recorded.

NASA insists it will be a near miss with no chance of the asteroid hitting Earth.

The U.S. space agency said Wednesday that this newly discovered asteroid will zoom 3,600 kilometres above the southern tip of South America. That’s 10 times closer than the bevy of communication satellites circling overhead.

The closest approach will occur at 7:27 p.m. ET.

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Even if the space rock came a lot closer, scientists said most of it would burn up in the atmosphere, with some of the bigger pieces possibly falling as meteorites.

NASA’s impact hazard assessment system, called Scout, quickly ruled out a strike, said its developer, Davide Farnocchia, an engineer at the agency’s Jet Propulsion Laboratory in Pasadena, Calif.

“But despite the very few observations, it was nonetheless able to predict that the asteroid would make an extraordinarily close approach with Earth,” Farnocchia said in a statement.

“In fact, this is one of the closest approaches by a known near-Earth object ever recorded.”

Asteroid spotted by amateur astronomer in Crimea

Discovered Saturday, the asteroid known as 2023 BU is believed to be 3.5 to 8.5 metres across.

It was first spotted by Gennady Borisov, the same amateur astronomer in Crimea who discovered an interstellar comet in 2019.

Within a few days, dozens of observations were made by astronomers around the world, allowing them to refine the asteroid’s orbit.

The asteroid’s path will be drastically altered by Earth’s gravity once it zips by. Instead of circling the sun every 359 days, it will move into an oval orbit lasting 425 days, according to NASA.

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Nuclear-powered spaceships? U.S. plans for 2027

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WASHINGTON –

The United States plans to test a spacecraft engine powered by nuclear fission by 2027 as part of a long-term NASA effort to demonstrate more efficient methods of propelling astronauts to Mars in the future, the space agency’s chief said on Tuesday.

NASA will partner with the U.S. military’s research and development agency, DARPA, to develop a nuclear thermal propulsion engine and launch it to space “as soon as 2027,” NASA administrator Bill Nelson said during a conference in National Harbor, Maryland.

The U.S. space agency has studied for decades the concept of nuclear thermal propulsion, which introduces heat from a nuclear fission reactor to a hydrogen propellant in order to provide a thrust believed to be far more efficient than traditional chemical-based rocket engines.

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NASA officials view nuclear thermal propulsion as crucial for sending humans beyond the moon and deeper into space. A trip to Mars from Earth using the technology could take roughly four months instead of some nine months with a conventional, chemically powered engine, engineers say.

That would substantially reduce the time astronauts would be exposed to deep-space radiation and would also require fewer supplies, such as food and other cargo, during a trip to Mars.

“If we have swifter trips for humans, they are safer trips,” NASA deputy administrator and former astronaut Pam Melroy said Tuesday.

The planned 2027 demonstration, part of an existing DARPA research program that NASA is now joining, could also inform the ambitions of the U.S. Space Force, which has envisioned deploying nuclear reactor-powered spacecraft capable of moving other satellites orbiting near the moon, DARPA and NASA officials said.

DARPA in 2021 awarded funds to General Atomics, Lockheed Martin and Jeff Bezos’ space company Blue Origin to study designs of nuclear reactors and spacecraft. By around March, the agency will pick a company to build the nuclear spacecraft for the 2027 demonstration, the program’s manager Tabitha Dodson said in an interview.

The joint NASA-DARPA effort’s budget is US$110 million for fiscal year 2023 and is expected to be hundreds of millions of dollars more through 2027.

Reporting by Joey Roulette; Editing by Chizu Nomiyama and David Gregorio

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The green comet ZTF returns to the solar system 50,000 years later… and it will be visible from Earth

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For astronomy enthusiasts, February 1 is marked in red on their calendars. The reason: it is not every day that there is a chance to see a green comet.

In fact, it is the first time in 50,000 years that C/2022 ZTF will return to the solar system. And it will be early next month when it will reach its closest position to Earth.

Specifically, the green comet ZTF will pass 42 million light years from our planet. Experts are not 100 percent sure whether it will be visible from the surface without the use of any instrument. However, if we have specific astronomy binoculars or telescopes, we will be able to see it without any problem.

As usually happens in these cases, the best places to observe the comet, this one or any other, are places with little artificial light. That is to say, we should move away from urban centres and it is preferable to do so in the hours before dawn.

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Un cometa brillante, visto desde California.Getty

Why is comet ZTF green?

Comet ZTF has a brightness and a colour that, although not unique, is clearly distinctive. Its hue is due to the fact that it is composed, among other materials, of diatomic carbon.

When it comes into contact with sunlight, the decomposition of this element causes the gas to acquire this spectacular colour.

Comet ZTF was discovered in March 2022

Un telescopio apunta al cielo.
Un telescopio apunta al cielo.Getty

Frank Masci and Bryce Bolin of the Palomar Observatory in California were responsible for spotting the striking comet ZTF in the sky. It is so named because its discovery is part of the Zwicky Transient Facility surveillance programme, which uses the powerful Schmidt telescope at the facility.

Initially, the scientists responsible for the discovery thought it was an asteroid, but they quickly realised that this was not the case. Despite the striking colour of this comet, experts advise keeping expectations low. In any case, it is an event that has aroused great interest in the community.

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