WASHINGTON (Reuters) – Droplets of glass dug up in New Jersey and from the Atlantic seabed indicate a comet or some other extraterrestrial object may have smacked Earth 56 million years ago, roughly 10 million years after the asteroid impact that doomed the dinosaurs.
Scientists said on Thursday the collision may have triggered a particularly warm, ice-free period on Earth when important mammalian groups, including the primate lineage that led to humans, appeared for the first time.
The findings, published in the journal Science, marked the latest evidence of the profound influence that past impacts by celestial bodies have had on life on Earth.
The tiny spherical bits of dark glass, called microtektites, represent strong evidence of a collision with a comet or asteroid, the researchers said. They form when a space rock hits Earth’s surface and vaporizes the spot where it lands, ejecting into the air bits of molten rock that solidify into glass.
The microtektites were excavated from a geological layer marking the start of the Eocene Epoch about 56 million years ago from three sites in southern New Jersey (Millville, Wilson Lake and Medford) and an underwater site east of Florida.
A tiny sand-grain-size tektites, thought to be created when vaporized material from an impact solidified while flying through the air, is shown in this image released in New York, U.S., October 13, 2016. Courtesy Megan Fung/Handout via REUTERS
That coincided with the beginning of a warming event, called the Paleocene-Eocene Thermal Maximum, associated with an accumulation of atmospheric carbon dioxide. It lasted more than 100,000 years and drove up global temperatures about 9-14 degrees Fahrenheit (5-8 degrees Celsius).
The impact of an asteroid about six miles wide (10 km) off Mexico’s Yucatan Peninsula 10 million years earlier killed off many marine and terrestrial creatures including the dinosaurs and enabled mammals to gain supremacy.
No such mass extinction was associated with the event 56 million years ago, although many single-celled ocean-bottom creatures disappeared. During the warming period, primates and two mammal groups — one that includes deer, antelope, sheep and goats and another that includes horses and rhinos — first appear in the fossil record.
The researchers said they have not found the location of an impact crater linked to the collision. They said geological evidence suggested the object was a comet.
“We can’t really say where it was, or how big, at this point,” said geochemist Morgan Schaller of Rensselaer Polytechnic Institute, who led the study.
While the findings are not proof that the impact caused the warming period, they are “a rather dramatic finding in support of an impact trigger” for the climate changes, said planetary scientist Dennis Kent of Columbia University’s Lamont-Doherty Earth Observatory and Rutgers University.
By Will Dunham
(Reporting by Will Dunham; Editing by Sandra Maler)
CAPE CANAVERAL, Fla. (Reuters) – Scientists for the first time have directly detected key organic compounds in a comet, bolstering the notion that these celestial objects delivered such chemical building blocks for life long ago to Earth and throughout the solar system.
The European Space Agency’s Rosetta spacecraft made several detections of the amino acid glycine, used by living organisms to make proteins, in the cloud of gas and dust surrounding Comet 67P/Churyumov-Gerasimenko, scientists said on Friday.
Glycine previously was indirectly detected in samples returned to Earth in 2006 from another comet, Wild 2. But there were contamination issues with the samples, which landed in the Utah desert, that complicated the scientific analysis.
“Having found glycine in more than one comet shows that neither Wild 2 nor 67P are exceptions,” said Rosetta scientist Kathrin Altwegg of the University of Bern in Switzerland, who led the research published in the journal Science Advances.
The discovery implies that glycine is a common ingredient in regions of the universe where stars and planets have formed, Altwegg said.
“Amino acids are everywhere, and life could possibly also start in many places in the universe,” Altwegg added.
Altwegg and colleagues also found phosphorus, a key element in all living organisms, and other organic molecules in dust surrounding comet 67P. It was the first time phosphorus was found around a comet.Scientists have long debated the circumstances around the origin of life on Earth billions of years ago, including the hypothesis that comets and asteroids carrying organic molecules crashed into the oceans on the Earth early in its history.”Meteorites and now comets prove that Earth has been seeded with many critical biomolecules over its entire history,” said University of Washington astronomer Donald Brownlee, who led NASA’s Stardust comet sample return mission. Scientists plan to use Rosetta to look for other complex organic compounds around the same comet.
“You need more than amino acids to form a living cell,” Altwegg said. “It’s the multitude of molecules which make up the ingredients for life.” Rosetta is due to end its two-year mission at 67P by flying very close to the comet and then crash-land onto its surface this September.
67P is in an elliptical orbit that loops around the sun between the orbits of the planets Jupiter and Earth. The comet is heading back out toward Jupiter after reaching its closest approach to the sun last August.
(Reporting by Irene Klotz; Editing by Will Dunham)
CAPE CANAVERAL, Fla. (Reuters) – Astronomers have found a first-of-its-kind tailless comet whose composition may offer clues into long-standing questions about the solar system’s formation and evolution, according to research published on Friday in the journal Science Advances.
The so-called “Manx” comet, named after a breed of cats without tails, was made of rocky materials that are normally found near Earth. Most comets are made of ice and other frozen compounds and were formed in solar system’s frigid far reaches.
Researchers believe the newly found comet was formed in the same region as Earth, then booted to the solar system’s backyard like a gravitational slingshot as planets jostled for position.
Scientists involved in the discovery now seek to learn how many more Manx comets exist, which could help to resolve debate over exactly how and when the solar system settled into its current configuration.
“Depending how many we find, we will know whether the giant planets danced across the solar system when they were young, or if they grew up quietly without moving much,” paper co-author Olivier Hainaut, an astronomer with the European Southern Observatory in Germany, said in a statement.
The new comet, known as C/2014 S3, was discovered in 2014 by the Panoramic Survey Telescope and Rapid Response System, or Pan-STARRS. This network of telescopes scours the night-time skies for fast-moving comets, asteroids and other celestial bodies.
Typically comets coming in from the same region as the Manx grow bright tails as they approach the sun, the result of ice vaporizing off their bodies and gleaming in reflected sunlight.
But C/2014 S3 was dark and virtually tailless when it was spotted about twice as far away from the sun as Earth.
Later analysis showed that instead of ices typically found on comets, the Manx comet contained materials similar to the rocky asteroids located in a belt between Mars and Jupiter.
And C/2014 S3 appeared pristine, an indication that it had been in the solar system’s deep freeze for a long time, said University of Hawaii astronomer Karen Meech, the lead author.
The discovery of additional Manx comets could help scientists to refine computer models used to simulate the solar system’s formation, Meech said.
(Reporting by Irene Klotz; editing by Letitia Stein and Diane Craft)
Comet 67P/Churyumov-Gerasimenko was captured in this stunning image by the ESA’s Rosetta spacecraft.
If you follow us on Facebook you already know about Comet 67P. If you don’t, Comet 67P is travelling through space at 135,000 km/h (38 km/s; 84,000 mph) and is approximately 4.3 by 4.1 km (2.7 by 2.5 mi) at its longest and widest dimensions.
In this amazing image you’re seeing a perfect alignment of the sun behind the comet, while Rosetta is positioned perfectly to capture the glow of the sun’s light around the comet’s silhouette.
Rosetta was able to capture this amazing image because it led a mission to sit in 67p’s orbit “In February and March, Rosetta spent several weeks at very close distances from the comet nucleus, which overfilled the field of view of the NAVCAM, providing us with striking views of the surface,” ESA mentions in a blog post. “During the current excursion, instead, we can enjoy again a view of the full nucleus and the environment around it.”
Rosetta rested at 1,000 kilometers (620 miles) from the comet on March 30th, but is now moving below 200 kilometers (125 miles) and lowering itself to 30 kilometers (19 miles) on April 9th.
The ESA’s Rosetta mission is scheduled to come to a close later this year in September. The plan is to gently lower it into the comet’s orbit until eventually landing it on 67P’s surface – this will result in Rosetta’s untimely end as the comet will block the antennas from communicating with Earth.
In the meantime, we’re hoping we get a few more amazing images like these.
Two comets will fly by Earth over the next two days. One of them will be the third closest flyby in recorded history.
Comet 252P/LINEAR was discovered by M.I.T.’s LINEAR survey roughly 16 years ago. It’s about 230 meters long and is currently passing by our planet (at the time of this article) at a distance of over 5.2 million kilometers (or 3.3 millions miles).
The second comet is P/2016 BA14, which was discovered only this year by the University of Hawaii’s PanSTARRS telescope on the island of Maui. This comet was initially thought to be an asteroid, but follow-up observations revealed its true nature. On march 22, P/2016 BA14 will have it’s closest approach to Earth at 2:30pm GMT (10:30 a.m. EST) at a distance of 3.5 million kilometers (2.2 million miles). This is the closest comet approach to Earth since 1770 when Lexell’s Comet passed by the planet at 2.2 million kilometers (1.4 million miles).
The comets have similar orbital paths, and some scientists speculate that this may all be part of one comet. “Perhaps during a previous pass through the inner Solar System, or during a distant flyby of Jupiter, a chunk that we now know of as BA14 might have broken off 252P”, says Paul Chodas, manager of NASA’s Center for Near-Earth Object Studies.
To view either of these comets you may need a pretty good telescope. At the distance of it’s closest pass, BA14 will be roughly nine times the distance of the Earth to the Moon.
252P on the other hand is expected to be over 100 times brighter than its closer counter-part. Some believe it will even be fully visible to the naked eye.
FRANKFURT (Reuters) – European scientists have given up hope of restoring contact with space probe Philae, which successfully landed on a comet in a pinpoint operation only to lose power because its solar-driven batteries were in the shade.
The German Aerospace Center (DLR) said on Friday it suspects Philae is now covered in dust and too cold to operate.
“Unfortunately, the probability of Philae re-establishing contact with our team at the DLR Lander Control Center is almost zero, and we will no longer be sending any commands,” Stephan Ulamec, Philae Project Manager of the DLR, said in a statement.
Philae came to rest on a comet in November 2014 in what was considered a remarkable feat of precision space travel. But it closed down soon after because it was in the shade and could not be recharged.
The probe woke up in June as the comet approached the sun, giving scientists hope that the lander could complete some experiments that it had not done before its solar-powered batteries ran out.
But the lander has not made contact with its Rosetta orbiter since July 9, and a last-ditch attempt to re-establish contact with the robotic lab has failed.
“It would be very surprising if we received a signal now,” Ulamec said.
While the project team believes that Philae is likely ice-free, the solar panels that recharge its batteries are probably covered with dust.
In addition, night-time temperatures can now fall below 180 degrees Celsius below zero (-292°F) as comet 67P/Churyumov-Gerasimenko moves away from the sun, which is much colder than Philae was designed to withstand.
While Philae did not have as much time as initially hoped after landing for experiments, information it has collected is reshaping thinking about comets, and it has been a useful lesson for designing future missions.
Scientists expect to get a final glimpse of the lander in the European summer, when the Rosetta spacecraft snaps some pictures during close fly-bys, before landing on the comet itself when its mission ends in September.
And in around six years, Philae and Rosetta will near the Earth again when the comet returns to circle the sun again.
Rosetta is a mission of the European Space Agency, with contributions from its member states and U.S. space agency NASA. The Philae lander was provided by a consortium headed by the DLR.
(Editing by Jeremy Gaunt)
Russia, you’re crazy.
This is not an attempt to recreate Armageddon. This is a real proposal.
Russian news agency TASS is reporting that regional scientists believe detonating a nuclear weapon near an asteroid (as opposed to on, or in it) would deflect an asteroids course just enough to miss earth – if the explosion occurred within a specific point at an asteroids trajectory.
This isn’t the first time we’ve heard the nuclear proposal; There was an emergency defense project that proposed to destroy asteroids with nuclear bombs in 2014, and a NASA/ESA led Asteroid Impact and Deflection Mission is currently in play for a launch in 2022.
The Russian proposal is known as the NEOShield project.
The work was distributed among different participants from various countries, and the task on deflecting hazardous space objects by nuclear explosions was placed with Russia, represented by the Central Machine Building Research Institute.
Over the next few years studies will be conducted as to exactly what size of explosion would be required to have the desired effect.
DID YOU KNOW: Launching a nuclear weapon into space is currently banned
“However, if due to an asteroid threat will rise the issue of enormous damage or even the very existence of life on the Earth, those bans, of course, will be dropped,” a statement from Roscosmos.
At the moment, we do not know of any asteroids on an immediate collison course with Earth. However, in 2029 and 2036, Apothis will come so close to earth, it will pass right under the orbit of our geo-synchronous satellites.
Our chances of being hit by an asteroid are slim, as far as we know, but most believe it to be a simple inevitability. Having measures against these occurrences is not a far fetched idea.
There are massive comets called ‘centaurs’ that could be the inevitable destroyers of life on earth. These comets measure 50 to 100 kilometers (30 to 60 miles) across and have been recently identified in the region just beyond Neptune.
These centaurs have the ability to travel towards the inner planets of our solar system as they become redirected by the gravitational pull of Neptune, Uranus, and Saturn. A review from the Armagh Observatory and the University of Buckingham estimates that centaurs are likely to cross Earth’s orbit ever 40,000 to 100,000 years.
The effects on a planet like Earth from a centaur impact are highly unpredictable; Centaurs are believed to be incredibly unstable, potential catastrophic events would be caused by dust and other small fragments and the centaur shatters into Earth’s orbit. In the diagram below you’ll see that no centaurs cross Earth’s immediate orbit, however due to the disintegration factor this does not mean we are out of harm’s way.
One single centaur measuring 100 kilometers could contain roughly 100 times the mass of all the Earth-crossing asteroids detected to date.
This means dust, and a lot of it. Researches believe that a centaur impact on that scale would fill the Earth’s atmosphere with tiny particles that would reduce to the amount of sunlight to “moonlight levels” for roughly 100,000 years. If somehow life were to survive the impact, the shielding would put a stop to our ways of life as we know it.
And now, the orbits of the giant comets:
Here’s a diagram of our solar system showing the orbits of planets (blue) the orbits of deadly cenaturs (red) and the orbits of 17 trans-Neptunian objects (yellow)
Aside from the centaurs themselves, there exist fragments that extend several kilometers in length, that could generate catastrophic consequences. Similar to what may have led to the extinction of the dinosaurs. According to the study, several of these occurrences have happened in our past; The authors specifically cite craters in the Gulf of Mexica, Ukraine, Siberia and Chesapeake Ba
There is a high probability that a centaur crosses with Earth’s orbit at some point in the near future (in astronomical terms). The volume of debris and disintegration factor of these objects make it highly inevitable that at least some form of impact will occur. It would be difficult to determine the effects of any such object without knowing it’s mass, speed, and many other objects – but generally, objects larger than 1 kilometer (0.6 miles) pose a significant threat to life on earth.
Currently NASA’s Spaceguard initiative is seeking to map up to 90% of near earth objects (NEOs) that are larger than 1 kilometer. The focus is primarily held on the asteroid belt that sits between Mars and Jupiter. Professor Bill Napier is calling for the scope of this search to be extended; the far reaches of our solar system contains large objects that may as well be hazardous to the existence of life on Earth.
Our work suggests we need to look beyond our immediate neighborhood and look out beyond the orbit of Jupiter to find centaurs. If we are right, then these distant comets could be a serious hazard, and it’s time to understand them better.