Asteroid deemed potential Earth threat

SpaceX launches 64 satellites at once

WASHINGTON, Dec 4, (Agencies): NASA’s deep space explorer Osiris-Rex flew on Monday to within a dozen miles of its destination, a skyscraper-sized asteroid believed to hold organic compounds fundamental to life as well as the potential to collide with Earth in about 150 years.

Launched in September 2016, Osiris-Rex embarked on NASA’s unprecedented seven-year mission to conduct a close-up survey of the asteroid Bennu, collect a sample from its surface and return that material to Earth for study.

Bennu, a rocky mass roughly a third of a mile wide and shaped like a giant acorn, orbits the sun at roughly the same distance as Earth and is thought to be rich in carbon-based organic molecules dating back to the earliest days of the solar system. Water, another vital component to the evolution of life, may also be trapped in the asteroid’s minerals.

Scientists believe that asteroids and comets crashing into early Earth delivered organic compounds and water that seeded the planet for life, and atomic-level analysis of samples from Bennu could help prove that theory. But there is another, more existential reason to study Bennu. Scientists estimate there is a one-in-2,700 chance of the asteroid slamming catastrophically into Earth 166 years from now. That probability ranks Bennu No. 2 on NASA’s catalog of 72 near-Earth objects potentially capable of hitting the planet.

Osiris-Rex will help scientists understand how heat radiated from the sun is gently steering Bennu on an increasingly menacing course through the solar system. That solar energy is believed to be nudging the asteroid ever closer toward Earth’s path each time the asteroid makes its closest approach to our planet every six years.

“By the time we collect the sample in 2020 we will have a much better idea of the probability that Bennu would impact Earth in the next 150 years,” mission spokeswoman Erin Morton said.

Scientists have estimated that in 2135 Bennu could pass closer to Earth than the moon, which orbits at a distance of about 250,000 miles, and possibly come closer still some time between 2175 and 2195.

Osiris-Rex reached the “preliminary survey” phase of its mission on Monday, soaring to within 12 miles of the asteroid. The spacecraft will pass just 1.2 miles from Bennu in late December, where it will enter the object’s gravitational pull.

From that stage, the spacecraft will begin gradually tightening its orbit around the asteroid, spiraling to within just 6 feet of its surface. Osiris-Rex will then extend its robot arm to snatch a sample of Bennu’s terrain in a “touch-and-go” maneuver set for July 2020.

Osiris-Rex will later fly back to Earth, jettisoning a capsule bearing the asteroid specimen for a parachute descent in the Utah desert in September 2023.

NASA is developing a strategy for deflecting Bennu, or any other

who regularly returned to play with the game even when there were no more nuts to win. (RTRS)

Parasite decimates clam:

With rapid efficiency, a mysterious parasite is seeking out and killing a giant species of clam found only in the Mediterranean Sea. Unless scientists can find a way of stopping it soon, they say the mollusk could go extinct.

For thousands of years, the emblematic noble pen shell has been intrinsically connected to human civilization. The largest bivalve in the Mediterranean can grow to more than a meter (three feet) long and has provided food and one of the world’s rarest materials: sea silk spun from fibers it uses to secure itself to the seabed. The mollusk also contributes to clear water by filtering out organic particulates.

The pen shell, Pinna nobilis, asteroid found to be on a collision course with Earth, by use of a special spacecraft to slam into the object hard enough to nudge it onto a safer path, said Lindley Johnson, a planetary defense officer with NASA’s Science Mission Directorate.

“But this is all dependent on the outcome of a very close approach that Bennu has with Earth in September 2135,” Johnson said. “We’ll just need to wait and see. Rather, our great-greatgrandchildren will need to see.”

SpaceX launched its Falcon 9 rocket on Monday, sending an unusual payload into space – 64 satellites at the same time, a US record.

And the company headed by US tech billionaire Elon Musk marked another milestone in its bid to make rockets more re-usable, like airplanes: the blast-off used a recycled booster for the third time.

California-based SpaceX has landed more than 30 of these boosters back on Earth, and has begun re-using them on subsequent missions.

In the past, companies have typically allowed rocket parts costing many millions of dollars to fall like junk into the ocean.

Monday’s landing of the first stage was flawless, like many before it.

Several minutes after liftoff, the tall, white portion of the rocket – known formally as the first stage – separated from the second stage.

The booster then fired its engines and made a controlled, upright landing on a platform in the Pacific Ocean, video from SpaceX’s live webcast showed.

Meanwhile, SpaceX has postponed its cargo launch to the International Space Station until Wednesday after mold was found on food bars for a mouse experiment bound for the orbiting outpost, NASA said.

The launch was initially set for Tuesday. The new time is 1:16 pm (1816 GMT) Wednesday.

“The launch was moved to Wednesday after mold was found on food bars for a rodent investigation prior to handover to SpaceX,” NASA said in a statement late Monday. “Teams will use the extra day to replace the food bars.” Some 40 mice are part of the experiment aimed at studying the effects of microgravity in the immune system.

The launch will be the 16th for SpaceX, as part of an ongoing contract with NASA to send supplies to the astronauts living at the space station.

Some 5,600 pounds (2,500 kilograms) of food, experiments and other gear is packed onto the unmanned Dragon cargo ship, which will blast off on a Falcon 9 rocket from Cape Canaveral, Florida.

has been on the European Union’s protected species list for decades because of overfishing, pollution and the destruction of its natural habitat, meaning any fishing is banned. But the ban is often poorly enforced, with the animal harvested for food or for its shell, which is used for decorative purposes. (AP)

Study hints at longevity:

Galapagos giant tortoises possess

genetic variants linked to DNA repair, immune response and cancer suppression – providing clues into their longevity, according to a study published Monday.

A team of international researchers sequenced the genomes of two such tortoises, including Lonesome George – the last known member of the subspecies Geochelone nigra abingdoni, who died in captivity on the Galapagos’s Santa Cruz Island in 2012.

They detected “lineage-specific variants affecting DNA repair genes, inflammatory mediators and genes related to cancer development,” according to the study published in the journal Nature Ecology & Evolution.

The Pacific island chain off mainland Ecuador is famous for its unique flora and fauna studied by Charles Darwin as he developed his theory of evolution. Twelve giant tortoise species still inhabit it.

Galapagos National Park director Jorge Carrion said uncovering the secrets of Lonesome George’s longevity will help with efforts to restore giant tortoise populations in the archipelago.

Giant tortoises, which can live for over 100 years in captivity, arrived in the volcanic Galapagos region three to four million years ago.

It is believed that ocean currents dispersed them around the islands, creating 15 different species – three of which are extinct.

The second giant tortoise studied was a member of a species found on islands of the Aldabra Atoll in the Seychelles. (AP)