New evidence shows giant meteorite impacts formed parts of the moon’s crust

The team noted that rock samples captured during the Apollo missions show remarkable variety in terms of geology.

Newly discovered evidence shows that the moon’s crust may have formed directly as a result of giant meteorite impacts.

New research published Monday in the journal Nature Astronomy shows one of nature’s most destructive events led to the creation of the moon’s unusual crust.

Led by the Royal Ontario Museum, a group of astronomers say the most ancient parts of the moon’s crust appears to have formed during the time of frequent massive meteorite impacts.

“Rocks on Earth are constantly being recycled, but the Moon doesn’t exhibit plate tectonics or volcanism, allowing older rocks to be preserved,” explains Dr. Lee White, Hatch Postdoctoral Fellow at the ROM. “By studying the Moon, we can better understand the earliest history of our planet. If large, super-heated impacts were creating rocks on the Moon, the same process was probably happening here on Earth”.

The team noted that rock samples captured during the Apollo missions in the 1960s and 1970s show remarkable variety in terms of geology. The variations found contain mineralogical evidence that it formed at incredibly high temperatures (in excess of 2300 °C/ 4300 °F), which is only achievable by the melting of the outer layer of a planet in a large impact event.

“By first looking at this rock, I was amazed by how differently the minerals look compared to other Apollo 17 samples,” says Dr. Ana Cernok, Hatch Postdoctoral Fellow at the ROM and co-author of the study. “Although smaller than a millimetre, the baddeleyite grain that caught our attention was the largest one I have ever seen in Apollo samples. This small grain is still holding the evidence for formation of an impact basin that was hundreds of kilometres in diameter. This is significant, because we do not see any evidence of these old impacts on Earth.”

ALMA photographs debris ring around young star Formalhaut

Disk’s chemical composition is strangely similar to that of comets in our solar system.

Using the Atacama Large Millimeter/submillimeter Array (ALMA), a team of scientists has captured the first ever complete image of a ring of icy dust surrounding the young star Formalhaut.

The complete millimeter-wavelength of the ring reveals it to be a well-defined structure of dust and gas with a composition surprisingly similar to that of comets in our solar system.

Located approximately 25 light years away, Formalhaut has a planet initially discovered in 2008. It is one of only about 20 nearby star systems whose orbiting planets have been directly imaged.

The debris ring is approximately two billion kilometers wide at a distance of about 20 billion kilometers from the star.

At about 440 million years old, the system is just one-tenth as old as our solar system and may be experiencing its own version of the Late Heavy Bombardment that ours underwent about four billion years ago, a period characterized by asteroids and comets left over from the system’s formation repeatedly slamming into its planets.

Impacts of exocomets crashing into one another in the outer regions of the Formalhaut system likely created the debris ring, scientists believe.

A previous attempt to image the debris ring with ALMA in 2012, when the telescope was still in the process of being built, revealed just half of the disk but already hinted at chemical similarities with our solar system’s comets.

Now, “ALMA has given us this staggeringly clear image of a fully formed debris disk. We can finally see the well-defined shape of the disk, which may tell us a great deal about the underlying planetary system responsible for its highly distinctive appearance,” noted Meredith MacGregor of the Harvard-Smithsonian Center for Astrophysics in Cambridge, MA, and lead author of two papers on the subject scheduled for publication in the Astrophysical Journal.

With the help of computer modeling, the researchers were able to pinpoint the exact location and shape of the disk. Based on its narrow shape, they believe it to be the product of the gravitational influence of planets orbiting the star.

Interestingly, the debris disk contains approximately the same high levels of both carbon monoxide and carbon dioxide found in our own solar system’s comets.

Impacts among numerous exocomets could be releasing these gases.

“This chemical kinship may indicate a similarity in comet formation conditions between the outer reaches of this planetary system and our own,” noted Luca Matra of the University of Cambridge in the UK and lead author of one of the two papers on the discovery.

 

 

Organics on Ceres are likely native

Distribution of organic materials is inconsistent with delivery by comets or asteroids.

Organic materials found on dwarf planet Ceres by NASA’s Dawn spacecraft are likely native to the small world, according to research by scientists at the Southwest Research Institute (SwRI) in San Antonio, Texas.

The researchers specifically focused on a localized region of organic-rich material near Ernutet Crater, a 32-mile- (52-km-) wide opening on Ceres’ northern hemisphere.

Two origins are theorized for these organic materials or carbon-based compounds. They could have been brought to Ceres by impacting asteroids or comets after the dwarf planet formed 4.5 billion years ago, or they could have been synthesized through an internal process on the dwarf planet.

Located at the boundary of the solar system’s rocky planets and gas giants, Ceres is composed of clays and both sodium- and ammonium-carbonates, all of which indicate the small planet underwent complex chemical evolution.

“Earlier research that focused on the geology of the organic-rich region on Ceres were inconclusive about their origin,” explained Simone Marchi, an SwRI principal investigator who presented the findings Wednesday at a press conference held at the American Astronomical Society’s 49th Division for Planetary Sciences Meeting in Provo, Utah.

“Recently, we more fully investigated the viability of organics arriving via an asteroid or comet impact.”

Through computer simulations, scientists considered a range of variables, including the sizes and velocities of impacting objects.

The simulations indicated comet-like objects that hit Ceres at very high velocities would have had their organic materials destroyed by a mechanism known as shock compression, in which total pressure is lost.

Impacting asteroids, which would have lower velocities, would hold onto between 20 and 30 percent of their organic materials, depending on the angle at which they hit.

However, the localized distribution of organic materials on Ceres is not consistent with what would be seen if those organics had been delivered by small asteroids from the belt between Mars and Jupiter.

While researchers admit they still do not have all the pieces of the puzzle when it comes to Ceres’ organics, “These findings indicate that the organics are likely to be native to Ceres,” Marchi said.

Ceres is geologically differentiated, with a rocky core and icy mantle, and may harbor a subsurface ocean that could possibly be home to microbial life.

NASA preparing to try and touch the Sun

NASA is gearing up to send its Parker Solar Probe on a bold mission to touch the Sun.

NASA is preparing to launch the Parker Solar Probe on a bold mission to touch the Sun. The mission will take place no earlier than August 8, 2018, and will consist of a United Launch Alliance Delta IV Heavy carrying the car-sized spacecraft closer to the Sun than any man-made object ever has.

“We’ve been studying the Sun for decades, and now we’re finally going to go where the action is,” said Alex Young, associate director for science in the Heliophysics Science Division at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

“The Sun’s energy is always flowing past our world,” said Nicky Fox, Parker Solar Probe’s project scientist at the Johns Hopkins University Applied Physics Lab in Laurel, Maryland. “And even though the solar wind is invisible, we can see it encircling the poles as the aurora, which are beautiful—but reveal the enormous amount of energy and particles that cascade into our atmosphere. We don’t have a strong understanding of the mechanisms that drive that wind toward us, and that’s what we’re heading out to discover.”

One of the breakthroughs that will allow the Parker Solar Probe to embark on this mission is its cutting-edge heat shield.

“The Thermal Protection System (the heat shield) is one of the spacecraft’s mission-enabling technologies,” said Andy Driesman, Parker Solar Probe project manager at the Johns Hopkins Applied Physics Lab. “It allows the spacecraft to operate at about room temperature.”

Why embark on such a crazy journey? To further our understanding of the universe.

“By studying our star, we can learn not only more about the Sun,” said Thomas Zurbuchen, the associate administrator for the Science Mission Directorate at NASA HQ. “We can also learn more about all the other stars throughout the galaxy, the universe and even life’s beginnings.”

‘Blood moon’ century’s longest eclipse, amazes viewers

The “blood moon” captivated viewers around the world in the century’s longest eclipse.

On Friday, the longest “blood moon” eclipse amazed skygazers around the world. Not only that, the event coincided with Mars’ closest approach in 15 years, making for a unique celestial spectacle.

“Until today I thought Mars, Jupiter and the other planets were in the imagination of scientists,” said Purity Sailepo of Maasai community southwest of the Kenyan capital Nairobi. “But now I’ve seen it I can believe it and I want to be an astronomer to tell other people.”

Unlike solar eclipses, viewers did not need to wear protective gear. The unique period of a complete eclipse is also known as “totality,” when the moon appears to be its darkest. It lasted for six hours and 14 minutes from 1714 to 2328 GMT.

“I hope this eclipse will bring us happiness and peace,” said Karima, 46, as she stared at the sky.

However, monsoon rainstorms hid the event from some observers. Not only that, but an overcast sky left some people watching from beaches and cliffs in the English county of Dorset with nothing to look at.

“It’s disappointing,” said Tish Adams, 67. “I took a few photos but there was nothing but a streak of pink in the sky.”

Interestingly, NASA called out some social media hoaxers that said Mars would look as big as the moon during the eclipse.

“If that were true, we’d be in big trouble given the gravitational pulls on Earth, Mars, and our moon!” the agency said.

Blue meteorite crystals reveal Sun’s ‘terrible twos’

A new study examines ancient blue meteorite crystals to shed light on the Sun’s highly active early years.

Although our Sun’s beginnings are shrouded in mystery, a new study that examines ancient blue meteorite crystals sheds light on the rowdy start of the Milky Way’s giant star.

“The Sun was very active in its early life—it had more eruptions and gave off a more intense stream of charged particles. I think of my son, he’s three, he’s very active too,” said Philipp Heck from University of Chicago and co-author of the study.

“Almost nothing in the Solar System is old enough to really confirm the early Sun’s activity, but these minerals from meteorites in the Field Museum’s collections are old enough,” he added. “They’re probably the first minerals that formed in the Solar System.”

The team examined the crystals using a state-of-the-art mass spectrometer in Switzerland to determine their chemical make-up. And in cobination with a laser, the team was able to melt a tiny grain of hibonite crystal in the meteorite, which in turn released the neon and helium trapped inside.

“We got a surprisingly large signal, clearly showing the presence of helium and neon—it was amazing,” said lead author Levke Kööp.

The new study is evidence that the Milky Way’s oldest materials went through an irradiation phase that younger materials were able to avoid.

“We think that this means that a major change occurred in the nascent Solar System after the hibonites had formed—perhaps the Sun’s activity decreased, or maybe later-formed materials were unable to travel to the disk regions in which irradiation was possible,” Kööp said.

“What I think is exciting is that this tells us about conditions in the earliest Solar System, and finally confirms a long-standing suspicion,” Heck added. “If we understand the past better, we’ll gain a better understanding of the physics and chemistry of our natural world.”

The findings were published in Nature Astronomy.

Scientists say they ‘can’t rule out’ alien life on Jupiter after new discovery

The discovery of water in Jupiter’s Great Red Spot suggests the possibility of alien life.

A team of researchers just discovered water clouds in Jupiter’s Great Red Spot. Following the discovery, scientists say they “can’t rule out” alien life on the planet.

“Water may play a critical role in Jupiter’s dynamic weather patterns, so this will help advance our understanding of what makes the planet’s atmosphere so turbulent,” said astrophysicist Máté Ádámkovics.

However, Ádámkovics cautions that the presence of water on Jupiter doesn’t mean it is a precursor to life.

“And, finally, where there’s the potential for liquid water, the possibility of life cannot be completely ruled out,” he said. “So, though it appears very unlikely, life on Jupiter is not beyond the range of our imaginations.”

The team hopes to eventually learn just how much water is on the planet and the role it plays.

“Water may play a critical role in Jupiter’s dynamic weather patterns, so this will help advance our understanding of what makes the planet’s atmosphere so turbulent,” Ádámkovics said.

The research team made the discovery using specially designed software to analyze data obtained from Jupiter.

“When I initially began, I started by running the data through. The code was already written and I was just plugging in new data sets and generating output files,” said researcher Rachel Conway.  “But then I began fixing errors and learning more about what was actually going on. I’m interested in everything and anything that’s out there, so learning more about what we don’t know is always cool.”

The findings were published in the Astronomical Journal.

Astronomers discover new details of ‘monster’ star-forming galaxies

A new study sheds light on the structure of the “monster galaxy” COSMOS-AzTEC-1.

An international team of researchers examining a “monster galaxy” located 12.4 billion light years away from the Earth revealed that they achieved a milestone: an angular resolution 10 times higher than ever before, revealing previously unknown structural details.

“Monster galaxies,” also known as extreme starburst galaxies, are believed to be the ancestors of giant galaxies like the current universe’s Milky Way. And the more we know about them, the more we will discover more about the formation and evolution of our galaxy’s ancient past.

“A real surprise is that this galaxy seen almost 13 billion years ago has a massive, ordered gas disk that is in regular rotation instead of what we had expected, which would have been some kind of a disordered train wreck that most theoretical studies had predicted,” said study co-author Min Yun.

Yun added that they did observe that the galaxy’s gas disk is now dynamically unstable, meaning that the entire disk that makes up the galaxy is undergoing an episode of starburst. This explains its large star formation rate, which is upwards of 1,000 times that of the Milky Way.

Ken-ichi Tadaki, lead author of the study, says that COSMOS-AzTEC-1 is rich in star ingredients. However, it was still difficult to determine the cosmic gas in the galaxy, even using the ALMA’s high sensitivity and high resolution.

“We found that there are two distinct large clouds several thousand light-years away from the center,” he said. “In most distant starburst galaxies, stars are actively formed in the center. So it is surprising to find off-center clouds.”

“How these galaxies have been able to amass such a large quantity of gas in the first place and then essentially turn the entire gas reserve into stars in the blink of an eye, cosmologically speaking, was a completely unknown question about which we could only speculate,” Yun added. “We have the first answers now.”

The findings were published in Nature.

Ancient quasar lights support quantum entanglement

A new study examines quasar light to provide the strongest evidence yet for quantum entanglement, or “spooky action at a distance.”

A new study just provided the strongest evidence yet for quantum entanglement, also known as “spooky action at a distance.” The physics concept states that an object can be changed, moved, or affected without mechanical contact by another object.

Using distance quasars, including one that emitted its light 12.2 billion years ago and another 7.8 billion years ago, the team determined the measurements necessary for pairs of entangled photons.

The results revealed correlations among over 30,000 photon pairs, which is far more than the limit initially calculated for classically-based mechanisms.

“If some conspiracy is happening to simulate quantum mechanics by a mechanism that is actually classical, that mechanism would have had to begin its operations — somehow knowing exactly when, where, and how this experiment was going to be done — at least 7.8 billion years ago,” said co-author Alan Guth of MIT. “That seems incredibly implausible, so we have very strong evidence that quantum mechanics is the right explanation.”

“The Earth is about 4.5 billion years old, so any alternative mechanism — different from quantum mechanics — that might have produced our results by exploiting this loophole would’ve had to be in place long before even there was a planet Earth, let alone an MIT,” added David Kaiser, also of MIT. “So we’ve pushed any alternative explanations back to very early in cosmic history.”

“It is fun to think about new types of experiments we can design in the future, but for now, we are very pleased that we were able to address this particular loophole so dramatically,” he added. “Our experiment with quasars puts extremely tight constraints on various alternatives to quantum mechanics. As strange as quantum mechanics may seem, it continues to match every experimental test we can devise.”

The findings were published in Physical Review Letters.

Watery exoplanets are more common than we thought, but not very accommodating

A new study suggests that watery exoplanets might be more common than we thought, but this doesn’t necessarily mean they are habitable.

New research suggests that watery planets outside of the Milky Way might be more common than we thought, comprising approximately 35 percent of exoplanets that are two to four times the size of the Earth. The finding stems from data gained from the Kepler Space Telescope and Gaia mission that suggest that plenty of planet masses are half water, compared to the 0.02 percent water that Earth contains.

Water is a necessary ingredient for extraterrestrial life and a basic component of biology, which is why it is so high on the list of exoplanet properties that astrobiologists look for when searching for life on other planets.

The new study found that over 4,000 candidate or confirmed exoplanets are 1.5 to 2.5 times the radius of the Earth. But when the team attempted to model the insides of these Earthlike planets, they found something interesting.

“We have looked at how mass relates to radius, and developed a model which might explain the relationship,” says Li Zeng, who led the research team. “The model indicates that those exoplanets which have a radius of around x1.5 Earth radius tend to be rocky planets (of typically x5 the mass of the Earth), while those with a radius of x2.5 Earth radius (with a mass around x10 that of the Earth) are probably water worlds.”

This means that roughly 35 percent of exoplanets larger than Earth are water worlds. However, most of these environments are more akin to pressure cookers than ideal places for life.

“This is water, but not as commonly found here on Earth,” Zeng said. “Their surface temperature is expected to be in the 200 to 500 degree Celsius (392º to 932º F) range. Their surface may be shrouded in a water-vapor-dominated atmosphere, with a liquid water layer underneath. Moving deeper, one would expect to find this water transforms into high-pressure ices before we reaching the solid rocky core. The beauty of the model is that it explains just how composition relates to the known facts about these planets.

“Our data indicate that about 35 percent of all known exoplanets which are bigger than Earth should be water-rich. These water worlds likely formed in similar ways to the giant planet cores (Jupiter, Saturn, Uranus, Neptune), which we find in our own solar system. The newly-launched TESS mission will find many more of them, with the help of ground-based spectroscopic follow-up. The next generation space telescope, the James Webb Space Telescope, will hopefully characterize the atmosphere of some of them. This is an exciting time for those interested in these remote worlds.”

The findings were presented at the Goldschmidt Conference.