Sunday, October 13, 2024

SPACE/COSMOS

NASA says comet expected to put on show in Earth fly-by


The Comet Neowise is visible in the sky over Shenandoah National Park near Front Royal, Virginia on July 18, 2020. A new comet discovered last year is expected to pass 44 million miles from Earth on Saturday. File Photo by Pat Benic/UPI | License Photo

Oct. 11 (UPI) -- A comet just discovered last year by observers will whizz past Earth from 44 million miles away but leave a trail of dust and gases visible to the naked eye, NASA said.

Comet Tsuchinshan-Atlas will make its closest approach to Earth on Saturday and won't be back for about 80,000 years, the space agency said. It is about two miles in diameter and its tail extends millions of miles.

Bill Cooke, of NASA's Meteoroid Environment Office at the Marshall Space Flight Center in Huntsville, Ala., said the comet will appear in the sky like a fireball.

"It's not going to zing across the sky like a meteor," Cooke said, according to CNN. "It will just appear to hang there, and it will slowly change position from night to night. If you can see [the comet] with your unaided eye, [using] the binoculars will knock your socks off."

It was discovered by the Purple Mountain Observatory in China and the Asteroid Terrestrial-impact Last Alert System, ATLAS, telescope in South Africa. Scientists believe the comet was formed from the Oort Cloud, a spherical shell that surrounds the solar system.

"Bright comets are very rare and are usually newcomers to the inner solar system," Cooke said.

Powerful solar flare to begin producing auroras and possible electrical disruptions



The European Space Agency astronaut Samantha Cristoforetti captured this image showing a golden aurora with a splash of red through the stars during the night of December 13, 2014. A new aurora is expected to be seen through much of the United States Thursday night. File Photo by NASA/UPI | License Photo

Oct. 10 (UPI) -- Space weather watchers are expecting a powerful solar flare from the sun to reach Earth Thursday evening giving off a light show of colorful auroras as far south as Alabama and northern California.

According to the National Weather Service's Space Weather Prediction Center, the geomagnetic storm, expected to be seen much farther south than usual, could last through Friday. The flare could also hamper digital communications, the power grid, and satellites.

The solar storm has been classified as a Level 4 on a 1 to 5 scale, by the center, indicating how unusual it is for a solar flare so powerful to reach Earth. NASA said the flare has been classified as an X-1.4,with the X-class noting the most intense flares with the number giving its strength.

"This coronal mass ejection has been analyzed and speed estimates are 1,200 to 1,300 kilometers (746 to 809 miles) per second," said the Space Weather Prediction Center. "We won't know the characteristics of the CME until it arrives 1 million miles from Earth and its speed and magnetic intensity are measured."

Solar flares are powerful bursts of energy occasionally released by the sun into the solar system. While Earth's atmosphere protects the planet from the worst parts of such flares like radiation, it can still play havoc with radio waves and satellite communications but often leaves beautiful auroras.

NASA’s Europa Clipper spacecraft will scour Jupiter moon for the ingredients for life

A massive NASA spacecraft is ready to set sail for Jupiter and its moon Europa. The craft named Europa Clipper will peer beneath the moon’s icy crust and determine whether conditions there could support life.



This illustration provided by NASA depicts the Europa Clipper spacecraft over the moon, Europa, with Jupiter at background left. (NASA/JPL-Caltech via AP)

This illustration provided by NASA depicts the Europa Clipper spacecraft above the surface of the moon Europa, foreground, and Jupiter behind.
 (NASA/JPL-Caltech via AP)

BY MARCIA DUNN

 October 12, 2024


CAPE CANAVERAL, Fla. (AP) — A NASA spacecraft is ready to set sail for Jupiter and its moon Europa, one of the best bets for finding life beyond Earth.

Europa Clipper will peer beneath the moon’s icy crust where an ocean is thought to be sloshing fairly close to the surface. It won’t search for life, but rather determine whether conditions there could support it. Another mission would be needed to flush out any microorganisms lurking there.

“It’s a chance for us to explore not a world that might have been habitable billions of years ago, but a world that might be habitable today — right now,” said program scientist Curt Niebur.

Its massive solar panels make Clipper the biggest craft built by NASA to investigate another planet. It will take 5 1/2 years to reach Jupiter and will sneak within 16 miles (25 kilometers) of Europa’s surface — considerably closer than any other spacecraft.

Liftoff is targeted for this month aboard SpaceX’s Falcon Heavy rocket from NASA’s Kennedy Space Center. Mission cost: $5.2 billion.
Europa, the superstar among Jupiter’s many moons

One of Jupiter’s 95 known moons, Europa is almost the size of our own moon. It’s encased in an ice sheet estimated to be 10 miles to 15 miles or more (15 kilometers to 24 kilometers) thick. Scientists believe this frozen crust hides an ocean that could be 80 miles (120 kilometers) or more deep. The Hubble Space Telescope has spotted what appear to be geysers erupting from the surface. Discovered by Galileo in 1610, Europa is one of the four so-called Galilean moons of Jupiter, along with Ganymede, Io and Callisto.


RELATED STORIES

NASA spacecraft to study Jupiter moon's underground ocean cleared for October launch

A spacecraft is on its way to a harmless asteroid slammed by NASA in a previous save-the-Earth test


NASA switches off instrument on Voyager 2 spacecraft to save power


Seeking conditions that support life

What type of life might Europa harbor? Besides water, organic compounds are needed for life as we know it, plus an energy source. In Europa’s case that could be thermal vents on the ocean floor. Deputy project scientist Bonnie Buratti imagines any life would be primitive like the bacterial life that originated in Earth’s deep ocean vents. “We will not know from this mission because we can’t see that deep,” she said. Unlike missions to Mars where habitability is one of many questions, Clipper’s sole job is to establish whether the moon could support life in its ocean or possibly in any pockets of water in the ice.

Supersized spacecraft

When its solar wings and antennas are unfurled, Clipper is about the size of a basketball court — more than 100 feet (30 meters) end to end — and weighs nearly 13,000 pounds (6,000 kilograms). The supersized solar panels are needed because of Jupiter’s distance from the sun. The main body — about the size of a camper — is packed with nine science instruments, including radar that will penetrate the ice, cameras that will map virtually the entire moon and tools to tease out the contents of Europa’s surface and tenuous atmosphere. The name hearkens to the swift sailing ships of centuries past.

Circling Jupiter to fly by Europa

The roundabout trip to Jupiter will span 1.8 billion miles (3 billion kilometers). For extra oomph, the spacecraft will swing past Mars early next year and then Earth in late 2026. It arrives at Jupiter in 2030 and begins science work the next year. While orbiting Jupiter, it will cross paths with Europa 49 times. The mission ends in 2034 with a planned crash into Ganymede — Jupiter’s biggest moon and the solar system’s too.

Europa flybys pose huge radiation risk

There’s more radiation around Jupiter than anywhere else in our solar system, besides the sun. Europa passes through Jupiter’s bands of radiation as it orbits the gas giant, making it especially menacing for spacecraft. That’s why Clipper’s electronics are inside a vault with dense aluminum and zinc walls. All this radiation would nix any life on Europa’s surface. But it could break down water molecules and, perhaps, release oxygen all the way down into the ocean that could possibly fuel sea life.

Earlier this year, NASA was in a panic that the spacecraft’s many transistors might not withstand the intense radiation. But after months of analysis, engineers concluded the mission could proceed as planned.

Other visitors to Jupiter and Europa

NASA’s twin Pioneer spacecraft and then two Voyagers swept past Jupiter in the 1970s. The Voyagers provided the first detailed photos of Europa but from quite a distance. NASA’s Galileo spacecraft had repeated flybys of the moon during the 1990s, passing as close as 124 miles (200 kilometers). Still in action around Jupiter, NASA’s Juno spacecraft has added to Europa’s photo album. Arriving at Jupiter a year after Clipper will be the European Space Agency’s Juice spacecraft, launched last year.

Ganymede and other possible ocean worlds

Like Europa, Jupiter’s jumbo moon Ganymede is thought to host an underground ocean. But its frozen shell is much thicker — possibly 100 miles (160 kilometers) thick — making it tougher to probe the environment below. Callisto’s ice sheet may be even thicker, possibly hiding an ocean. Saturn’s moon Enceladus has geysers shooting up, but it’s much farther than Jupiter. Ditto for Saturn’s moon Titan, also suspected of having a subterranean sea. While no ocean worlds have been confirmed beyond our solar system, scientists believe they’re out there — and may even be relatively common.

Messages in a cosmic bottle

Like many robotic explorers before it, Clipper bears messages from Earth. Attached to the electronics vault is a triangular metal plate. On one side is a design labeled “water words” with representations of the word for water in 104 languages. On the opposite side: a poem about the moon by U.S. poet laureate Ada Limon and a silicon chip containing the names of 2.6 million people who signed up to vicariously ride along.
___


The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.

No comments:

Post a Comment