Planetary ‘autopsies’ indicate worlds like Earth common in the cosmos

Planetary ‘autopsies’ indicate worlds like Earth common in the cosmos
By Will Dunham

WASHINGTON (Reuters) – A new way of studying planets in other solar systems – by doing sort of an autopsy on planetary wreckage devoured by a type of star called a white dwarf – is showing that rocky worlds with geochemistry similar to Earth may be quite common in the cosmos.

In a study published on Thursday, researchers studied six white dwarfs whose strong gravitational pull had sucked in shredded remnants of planets and other rocky bodies that had been in orbit. This material, they found, was very much like that present in rocky planets such as Earth and Mars in our solar system.

Given that Earth harbors an abundance of life, the findings offer the latest tantalizing evidence that planets similarly capable of hosting life exist in large numbers beyond our solar system.

“The more we find commonalities between planets made in our solar system and those around other stars, the more the odds are enhanced that the Earth is not unusual,” said Edward Young, a geochemistry and cosmochemistry professor at the University of California, Los Angeles (UCLA), who helped lead the study published in the journal Science. “The more Earth-like planets, the greater the odds for life as we understand it.”

The first planets beyond our solar system, called exoplanets, were spotted in the 1990s, but it has been tough for scientists to determine their composition. Studying white dwarfs offered a new avenue.

A white dwarf is the burned-out core of a sun-like star. In its death throes, the star blows off its outer layer and the rest collapses, forming an extremely dense and relatively small entity that represents one of the universe’s densest forms of matter, exceeded only by neutron stars and black holes.

Planets and other objects that once orbited it can be ejected into interstellar space. But if they stray near its immense gravitation field, they “will be shredded into dust, and that dust will begin to fall onto the star and sink out of sight,” said study lead author Alexandra Doyle, a UCLA graduate student in geochemistry and astrochemistry.

“This is where that ‘autopsy’ idea comes from,” Doyle added, noting that by observing the elements from the massacred planets and other objects inside the white dwarf scientists can understand their composition.

The researchers observed a fundamental characteristic of the rocks: their state of oxidation. The amount of oxygen present during the formation of these rocks was high – just as it was during the formation of our solar system’s rocky material. They focused on iron, which when oxidized ends up as rock.

“Rocks are rocks, even when they form around other stars,” Young said.

The closest of the six white dwarf stars is about 200 light-years from Earth. The farthest is about 665 light-years away.

(Reporting by Will Dunham; Editing by Sandra Maler)

Solar eclipse plunges Chile into darkness

A person observes a solar eclipse at Coquimbo, Chile, July 2, 2019. REUTERS/Rodrigo Garrido

SANTIAGO (Reuters) – Hundreds of thousands of tourists scattered across the north Chilean desert on Tuesday to experience a rare, and irresistible combination for astronomy buffs: a total eclipse of the sun viewed from beneath the world’s clearest skies.

A solar eclipse is observed at Coquimbo, Chile, July 2, 2019. REUTERS/Rodrigo Garrido

A solar eclipse is observed at Coquimbo, Chile, July 2, 2019. REUTERS/Rodrigo Garrido

A solar eclipse occurs when the moon passes between the Earth and the sun, plunging the planet into darkness. It happens only rarely in any given spot across the globe.

The best views this time were from Chile’s sprawling Atacama desert north of the coastal city of La Serena, where a lack of humidity and city lights combine to create the world’s clearest skies.

The region had not seen an eclipse since 1592, according to the Chilean Astronomy Society. The next one is expected in 2165.

Eclipse-watchers in Chile were not disappointed on Tuesday. The 95-mile (150-kilometer) band of total darkness moved eastward across the open Pacific Ocean late in the afternoon, making landfall in Chile at 4:38 p.m. EDT (2038 GMT).

Clear skies dominated from the South American country’s northern border with Peru south to the capital of Santiago, where office workers poured from buildings to catch a glimpse of the phenomenon.

Earlier in the day, a run on special “eclipse-viewing” glasses downtown had led to a shortage in many stores, with street vendors charging as much as $10 for a pair of the disposable, cardboard-framed lenses.

“This is something rare that we may never see again,” said Marcos Sanchez, a 53-year-old pensioner from Santiago who had purchased 16 of the lenses from an informal vendor downtown for himself and his family.

(Reporting by Dave Sherwood and Fabian Cambero; Editing by Sandra Maler)

Israeli spacecraft gets final element before 2019 moon launch

By Ari Rabinovitch

YEHUD, Israel (Reuters) – Israeli engineers on Monday added the final element to a spacecraft destined for the moon – a digital time capsule – and said they aimed to land the craft early next year, somewhere between the landing sites of Apollo 15 and 17.

It will be the first mission of its kind since 2013 and, if it is successful, Israel will be the fourth country to carry out a controlled “soft” landing of an unmanned vessel on the moon.

Since 1966, the United States and the former Soviet Union have put around a dozen of them on the moon and China last did so in 2013.

“The spacecraft is completely built, tested … and will be ready to ship to Cape Canaveral in a few weeks,” said Ido Anteby, CEO of the SpaceIL non-profit that has led the project.

Israel has launched satellites before, but this is the first longer-range Israeli spacecraft of its kind.

The craft, called Beresheet, Hebrew for Genesis, is shaped like a roundtable with four carbon-fiber legs, stands about 1.5 meters tall and weighs 585 kg (1,290 lb) – with fuel accounting for two-thirds of that weight.

It will blast off from Florida on a SpaceX Falcon 9 rocket in the next few months after an initial December date was pushed back.

The time capsule is a single, space-resilient disc, roughly the size of a CD, holding digital files of children’s drawings, photographs and information on Israeli culture and the history of humanity.

“The capsule will remain on the moon and stay in the environment of the moon and maybe in a couple tens of years someone will send a spacecraft to bring it back,” Anteby said.

Beresheet is also carrying a device to measure the moon’s magnetic fields.

SpaceIL is backed mainly by private donors, including U.S. casino magnate Sheldon Adelson and billionaire Morris Kahn who co-founded Amdocs, one of Israel’s biggest high-tech companies.

SpaceIL was founded in 2011 by a group of engineers with a budget of about $95 million. State-owned defense contractor Israel Aerospace Industries has collaborated in the project.

At 60,000 km (37,000 miles) above Earth, the spacecraft will split off from the Falcon launch vehicle. It will at first orbit Earth in expanding ellipses and, about two months later, cross into the moon’s orbit. It will then slow and carry out a soft landing which should cause no damage to the craft.

“Our landing site is located somewhere between the landing sites of Apollo 15 and Apollo 17,” Anteby said. “It’s a flat area. But still, it has small craters and a lot of boulders.”

(Reporting by Ari Rabinovitch; editing by Andrew Roche)

NASA deep space probe reaches asteroid deemed potential Earth threat

FILE PHOTO - NASA's Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) spacecraft is seen on display at Kennedy Space Center, Florida, U.S. August 20, 2016. REUTERS/Mike Brown

By Joey Roulette

(Reuters) – 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 sometime 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 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-great-grandchildren will need to see.”

(Reporting by Joey Roulette in Orlando, Fla.; Editing by Steve Gorman and Paul Tait)

Thousands gather in Israeli desert for meteor shower

Cars drive through Ramon Crater during the Perseid meteor shower near the town of Mitzpe Ramon, southern Israel, August 12, 2018. REUTERS/Amir Cohen

By Ori Lewis

MITZPE RAMON, Israel (Reuters) – Thousands of star-gazers gathered overnight at one of the darkest spots in Israel hoping to be dazzled by the annual Perseid meteor shower, only to be left somewhat disappointed by the show.

Locals had the rare task of directing traffic on a moonless Monday night in Mitzpe Ramon in the heart of the Negev Desert, a spot surrounded by terrain described as similar to a lunar or Martian landscape.

The Feinberg family from the Tel Aviv region drove for two-and-a-half hours for the display but the number of meteors, about one or fewer per minute, failed to truly light up the Ramon Crater’s dark night sky as in previous years.

A meteor streaks across the sky in the early morning during the Perseid meteor shower in Ramon Crater near the town of Mitzpe Ramon, southern Israel, August 13, 2018. REUTERS/Amir Cohen

A meteor streaks across the sky in the early morning during the Perseid meteor shower in Ramon Crater near the town of Mitzpe Ramon, southern Israel, August 13, 2018. REUTERS/Amir Cohen

“We are here waiting for the stars to fall, the children are very impatient,” said Eliran Feinberg, 42, who works for an air cargo company.

The Perseid meteors, which reach their peak every August, are produced by debris from the 109P/Swift-Tuttle comet that passes by the Earth every 133 years. It last passed in 1992.

Professor Rennan Barkana, head of the astrophysics department at Tel Aviv University, said this year’s shower was not as intense because the Earth had passed through a sparser part of the comet’s debris than previously and a smaller amount of particles had entered the atmosphere.

(Additional reporting by Daria Sito-Sucic in Sarajevo, Writing by Ori Lewis. Editing by Patrick Johnston)

Israel plans to land unmanned spacecraft on moon in February

Israeli scientists stand next to an unmanned spacecraft which an Israeli team plans to launch into space at the end of the year and to land it on the Moon next year, in Yahud, Israel, July 10, 2018 REUTERS/Ronen Zvulu

By Ari Rabinovitch

YEHUD, Israel (Reuters) – An Israeli non-profit group plans to land an unmanned spacecraft on the moon in February in the first landing of its kind since 2013.

The craft, which is shaped like a round table with four carbon fiber legs, is set to blast off in December from Florida’s Cape Canaveral aboard a SpaceX Falcon 9 rocket, said Ido Anteby, chief executive of the SpaceIL non-profit.

It aims to transmit pictures and videos back to earth over two days after it lands on Feb. 13 as well as measuring magnetic fields.

Ido Anteby, SpaceIL's CEO stands in front of an unmanned spacecraft which an Israeli team plans to launch into space at the end of the year and to land it on the Moon next year, in Yahud, Israel, July 10, 2018 REUTERS/Ronen Zvulun

Ido Anteby, SpaceIL’s CEO stands in front of an unmanned spacecraft which an Israeli team plans to launch into space at the end of the year and to land it on the Moon next year, in Yahud, Israel, July 10, 2018 REUTERS/Ronen Zvulun

“Our spacecraft will be the smallest ever to land on the moon,” said Anteby.

Since 1966, the United States and the former Soviet Union have put around 12 unmanned spacecraft on the moon using braking power to perform “soft” landings and China did so in 2013.

SpaceIL was founded in 2011 by a group of engineers with a budget of about $90 million and they had to sacrifice size and operational capabilities for more efficient travel.

The craft, unveiled on Tuesday at state-owned defense contractor Israel Aerospace Industries, stands about 1.5 meters high and weighs 585 kg (1,290 lb). The spacecraft has four carbon fiber legs and fuel takes up two-thirds of its weight.

At 60,000 km (37,000 miles) above Earth the spacecraft will deploy. It will orbit Earth in expanding ellipses and, about two months later, cross into the moon’s orbit. It will then slow and carry out a soft landing causing no damage to the craft.

“The landing is the most complicated part. The spot chosen is relatively flat and the spacecraft has eye contact with Earth for communication,” Anteby said. “From the moment the spacecraft reaches the point that it begins the landing, it will handle it totally autonomously.”

SpaceIL is backed mainly by private donors, including U.S. casino magnate Sheldon Adelson and billionaire Morris Kahn who co-founded Amdocs, one of Israel’s biggest high-tech companies.

(Editing by Matthew Mpoke Bigg)

Scientists puzzled by exotic distant galaxy lacking dark matter

The galaxy named NGC 1052-DF2, a large fuzzy-looking galaxy so diffused that astronomers call it a 'see-through' galaxy because its missing most, if not all of its dark matter, is shown in this photo obtained from NASA on March 28, 2018. NASA, ESA, and P. van Dokkum (Yale University)/Handout via REUTERS

By Will Dunham

WASHINGTON (Reuters) – Astronomers have detected for the first time a galaxy that is devoid of dark matter, the plentiful but enigmatic material that does not emit light or energy and had been considered a fundamental part of all galaxies including our own Milky Way.

The discovery, announced on Wednesday, is forcing scientists to rethink their ideas about the formation of galaxies.

“We didn’t expect that this could happen,” said Yale University astronomer Pieter van Dokkum, lead author of the research published in the journal Nature.

Paradoxically, the discovery of a galaxy without dark matter may actually confirm that the stuff actually exists by contradicting hypotheses advanced by dark matter doubters.

Van Dokkum said the galaxy, called NGC1052-DF2 and located about 65 million light years away from Earth, also appears to be devoid of gas and is relatively sparsely populated by stars.

It is about the same size as the Milky Way, but has roughly 250 times fewer stars: 400 million compared to the Milky Way’s 100 billion stars. It is classified as an ultra-diffuse galaxy, a kind first recognized in 2015.

Dark matter, which is invisible, is thought to comprise about a quarter of the universe’s combined mass and energy and about 80 percent of its total mass, but has not been directly observed. Scientists believe it exists based on gravitational effects it seems to exert on galaxies.

The universe’s ordinary matter includes things like gas, stars, black holes and planets, not to mention shoes, umbrellas, platypuses and whatever else you might see on Earth.

“Dark matter is not something that galaxies can sort of swap in or out of, like it’s kind of an optional thing that galaxies sometimes have and sometimes don’t,” van Dokkum said.

“We really thought that this is the essence of what a galaxy is, that galaxies are built from, initially, a bunch of dark matter and that all the stars and all the planets and everything else is just a little frost on top,” van Dokkum added.

The scientists spotted NGC1052-DF2 using the Dragonfly Telephoto Array, a telescope in New Mexico. They do not know how it formed, but have some hypotheses, including the possibility that a cataclysm within NGC1052-DF2 swept away all its gas and dark matter or that a massive nearby galaxy played havoc with it.

Van Dokkum said NGC1052-DF2 is so sparse that “it is literally a see-through galaxy.”

(Reporting by Will Dunham; Editing by Sandra Maler)

Scientists test warning system as asteroid flies by

Scientists test warning system as asteroid flies by

FRANKFURT (Reuters) – An asteroid the size of a school bus flew remarkably near Earth on Thursday, providing scientists with an opportunity to test the warning systems that would kick in if a space collision was coming.

Asteroid 2012 TC4 came close — passing Earth at a distance of only around 44,000 km (27,000 miles), which is nothing in Universe terms.

There was no actual risk of a hit, although the asteroid did come well inside the orbit of the Moon and that of some human-made satellites.

“Basically, we pretended that this is a ‘critical’ object with a high risk of impacting Earth … and exercised our communication channels and used telescopes and radar systems for observations,” Detlef Koschny of European Space Agency said in a blog post on the agency’s website.

The results were mixed.

Koschny said one big radar system in Puerto Rico did not work due to damage from Hurricane Maria but that another U.S. based radar system was used instead.

“This is exactly why we do this exercise – to not be surprised by these things,” he said.

Radar images showed the asteroid was about 10 to 12 meters (yards) wide, roughly the size of an asteroid that exploded over Chelyabinsk, Russia in 2013, leaving more than 1,000 people injured by flying glass and debris.

Koschny said the ESA now needed to update its predictions for how close 2012 TC4 will come to Earth on its next flyby, which has so far been forecast for 2079.

(Reporting by Maria Sheahan; Editing by Jeremy Gaunt)

Super Moon To grace Earth’s Skies in coming days

The super moon appears in the sky in Cairo, Egypt, in this file photo taken October 17, 2016.

By Irene Klotz

CAPE CANAVERAL, Fla. (Reuters) – The largest, brightest full moon in nearly seven decades will be on display in the coming days, promising Earth-bound sky-watchers a celestial “supermoon” spectacle.

The full moon will come nearer to Earth than at any time since 1948, astronomers said. At closest approach, which occurs at 6:23 a.m. EST on Monday, the moon will pass within 216,486 miles (348,400 km) of Earth’s surface, about 22,000 miles (35,400 km) closer than average, they added.

The moon’s distance from Earth varies because it is in an egg-shaped, not circular, orbit around the planet.

If skies are clear, the upcoming full moon will appear up to 14 percent bigger and 30 percent brighter than usual, making it what is called a supermoon, according to NASA. A supermoon occurs when the timing of a full moon overlaps with the point in the moon’s 28-day orbit that is closest to Earth. About every 14th full moon is a supermoon, said University of Wisconsin astronomer Jim Lattis.

People watch as a supermoon rises over Ciudad Juarez, Mexico, October 16, 2016.

People watch as a supermoon rises over Ciudad Juarez, Mexico, October 16, 2016. REUTERS/Jose Luis Gonzalez

The next time a full moon comes as close to Earth will be in 2034.

“If you could stack up full moons next to each other, there is clearly a difference,” Lattis said, but to a casual observer it is going to look very similar to a regular full moon.

Weather permitting, sky-watchers in North America and locations east of the International Dateline will have a better view on Sunday night since the moon will set less than three hours after closest approach on Monday.

“The difference in distance from one night to the next will be very subtle, so if it’s cloudy on Sunday, go out on Monday. Any time after sunset should be fine,” Noah Petro, deputy project scientist for NASA’s Lunar Reconnaissance Orbiter, said in a statement.

(Reporting by Irene Klotz; Editing by Will Dunham)

Scientists find Earth-like planet circling sun’s nearest neighbor

The planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to our Solar System, is seen in an undated artist's impression released by the European Southern Observatory

By Irene Klotz

(Reuters) – Scientists have discovered a planet that appears to be similar to Earth circling the star closest to the sun, potentially a major step in the quest to find out if life exists elsewhere in the universe, research published on Wednesday showed.

The relative proximity of the planet, known as Proxima b, gives scientists a better chance to eventually capture an image of it, to help them establish whether it has an atmosphere and water, which is believed to be necessary for life.

Future studies may reveal if any atmosphere contains tell-tale chemicals of biological life, such as methane, according to a paper published in this week’s issue of the journal Nature.

“The key question of our initiative was whether there were potentially life-bearing planets orbiting these stars. We know now there is at least one planet with some characteristics similar to the Earth,” said Pete Worden, a former top NASA manager, who was speaking at a European Southern Observatory webcast news conference to announce the find.

The planet, located about 4.2 light-years from Earth, or 25 trillion miles (40 trillion km), is the closest of some 3,500 planets that have been discovered beyond the solar system since 1995, according to the paper.

“This planetary system is much closer than any other that we know so detailed investigation is easier,” astronomer Ansgar Reiners, with the University of Gottingen in Germany, told reporters on a conference call.

Astronomers got their first hint of a planet circling the sun’s small dim neighbor star in 2013. But they needed additional observations, using more precise instruments, to make a definitive call.

An international team of 31 scientists found the planet after careful and repeated measurements of slight shifts in the color of the light coming from its host star, Proxima Centauri, which is a small, dim star in the Alpha Centauri system.

The shifts, which astronomers call “wobbles,” are caused by the gravitational tugging of a planet roughly 1.3 times the size of Earth on the parent star. Based on the timing of wobbles, scientists determined that the planet circles its host star in just 11 days, compared to Earth’s 365-day orbit around the sun.

That puts the planet far closer to its parent star than Earth orbits the sun. However, Proxima Centauri is so much smaller and dimmer than the sun that its planet’s orbit is suitably positioned for liquid water despite being just 4.4 million miles away.

EARTH-LIKE PLANET

“Chances are good that it’s a viable, Earth-like planet today,” said astronomer Pedro Amado, with the Instituto de Astrofísica de Andalucía in Granada, Spain.

But scientists are unsure if red dwarf stars like Proxima Centauri are good hosts for life. Planets orbiting close enough to keep water liquid would be blasted with 100 times more high-energy radiation than Earth receives from the sun, though what impact that would have on life is a matter of scientific debate.

“We don’t think it’s a show-stopper,” Amado said.

Magnetic fields and an atmosphere offer a planet some protection. It is unknown if Proxima b has either.

Before the discovery of Proxima b, the nearest Earth-like planet to the sun was circling a star known as Wolf 1061, located about 14 light-years away.

Proxima b may not be flying solo. “We have some suspicions that there is another signal around the star,” Reiners said.

More research is needed to determine if there are multiple planets circling Proxima Centauri.

The discovery announced on Wednesday is expected to bolster a $100 million project unveiled in April and backed by Russian billionaire Yuri Milner to develop a miniature laser-powered spacecraft that can make the trip to the Alpha Centauri system in about 20 years.

“We hope to build a whole system that will send nanocraft to Proxima Centauri and Alpha Centauri within a generation,” said Worden, the executive director of Breakthrough Starshot, an initiative that aims to deploy thousands of tiny spacecraft to travel to our nearest neighboring star system and send back pictures.

(Reporting by Irene Klotz in Sydney, Australia; Additional reporting by Rosalba O’Brien in Santiago; Editing by Bill Rigby and Alistair Bell)