Month: June 2019

‘Bathtub Rings’ Around Titan’s Lakes Might Be Made Of Alien Crystals

The frigid lakeshores of Saturn’s moon Titan might be encrusted with strange, unearthly minerals, according to new research being presented here.

Scientists re-creating Titan-esque conditions in their laboratory have discovered new compounds and minerals not found on Earth, including a co-crystal made of solid acetylene and butane.

Acetylene and butane exist on Earth as gases and are commonly used for welding and camp stove fuel. On Titan, with its extremely cold temperatures, acetylene and butane are solid and combine to form crystals, the new research found.

The new mineral might be responsible for the bathtub rings that are suspected to exist around Titan’s hydrocarbon lakes, according to Morgan Cable of NASA’s Jet Propulsion Laboratory at the California Institute of Technology, who will present the new research Monday at the 2019 Astrobiology Science Conference.

Titan’s lakes are filled with liquid hydrocarbons. Previous research using images and data gathered during the Cassini mission has shown that lakes in the moon’s dry regions near the equator contain signs of evaporated material left behind, like rings on a bathtub.

To create Titan-like conditions in the laboratory, the researchers started with a custom-built cryostat, an apparatus to keep things cold. They filled the cryostat with liquid nitrogen to bring the temperature down. They then warmed the chamber slightly, so the nitrogen turned to gas, which is mostly what Titan’s atmosphere contains. Next, they threw in what abounds on Titan, methane and ethane, as well as other carbon-containing molecules, and looked for what formed.

The first things to drop out of their Titan hydrocarbon soup were benzene crystals. Benzene is perhaps best known as a component of gasoline and is a snowflake-shaped molecule made out of a hexagonal ring of carbon atoms. But Titan benzene held a surprise: The molecules rearranged themselves and allowed ethane molecules inside, creating a co-crystal.

The researchers then discovered the acetylene and butane co-crystal, which is probably a lot more common on Titan than benzene crystals, based on what’s known about the moon’s composition, Cable said.

In the moon’s cold climate, the acetylene-butane co-crystals might form rings around the moon’s lakes as the liquid hydrocarbons evaporate and the minerals drop out — in the same way that salts can form crusts on the shores of Earth’s lakes and seas, according to Cable.

To confirm whether Titan has bathtub rings of co-crystals and other, undiscovered, hydrocarbon crystals, scientists will have to wait until a spacecraft can visit the shorelines of this moon, Cable said.

“We don’t know yet if we have these bathtub rings,” Cable said. “It’s hard to see through Titan’s hazy atmosphere.”

Papua New Guinea’s Mount Ulawun Volcano Erupts And Sends Thousands Of Residents Fleeing

More than 5,000 people have been forced to flee their homes after a volcano erupted in a remote part of Papua New Guinea’s West New Britain, local media have reported.

Eyewitness accounts online showed people evacuating their homes, as a large column of black smoke and red lava spewed from the crater of Mount Ulawun, known to be one of the most hazardous volcanos in the world.

Satellite imagery showed the eruption plume reaching heights of between 13 and 15 kilometres.

Volcanic activity began around 7:00am on Wednesday, with rumbling and booming noises heard throughout the day and an eruption warning was issued prompting an evacuation.

Flights have been cancelled into nearby Hoskins Airport and lava has cut off the New Britain Highway in three different locations, according to local media.

Pilot Eroli Tamara took images of rising smoke as she flew past yesterday afternoon.

“The top of the ash cloud did look to extend well up to 30,000-40,000 feet [10-12 kilometres],” she told the ABC.

Papua New Guinea Post Courier reported that more than 5,000 people have been evacuated so far, but a shortage of vehicles has slowed down the process.

A local community leader told the Post Courier that only five vehicles had been working non-stop to ferry people from the danger zone.

“The Government did not come to help and we had to use whatever means we had to move people,” Christopher Lagisa, a village elder and local palm oil estate owner told the ABC.

Mr Lagisa said that due to lava flows and ash, the local community had to be moved around 20-30 kilometres from the base of the mountain.

He said government disaster officials did not arrive until the evening and foreign companies working in the area did not offer their vehicles to assist in the evacuation.

“I don’t know why the Government came in very late,” he said adding that officials were now arranging for supplies of food and water that will hopefully be delivered today.

Mr Lagisa said the volcano had been monitored all night, but so far there were no reports of injuries or damage to homes.

He said the evacuation notice was expected to last about a week, but the eruption was already appearing to dissipate.

Ulawun is the highest and steepest of all the volcanoes in PNG and is considered to be one of the six ‘high-risk’ volcanoes in the country, according to the Papua New Guinea Geological Survey.

While Ulawun has produced small eruptions periodically for the past few decades, the last eruptions of this scale occurred in September 2000 and again in May 2001.

Tropical Storm Sepat To Threaten Japan With Flooding Downpours, Mudslides

Across the West Pacific, Tropical Storm Sepat will bring the potential for flooding and other impacts to Japan through Friday.

A tropical depression strengthened into Tropical Storm Sepat as it tracked south of mainland Japan on Thursday night, local time. The storm is also called Dodong in the Philippines.

The main impacts of Sepat will be rough surf and heavy rain across Japan.

Rain will expand over Shikoku and Honshu into Thursday night. Tokyo is expected to escape the heaviest rainfall on Thursday; however, a few downpours are possible late Thursday night into Friday morning.

The downpours lingering into Friday morning could result in a slower morning commute for the Greater Tokyo Area.

These downpours will increase the risk of flash flooding while also heightening the risk of mudslides, especially in areas of rugged terrain.

Another non-tropical storm system will spread a round of heavy rain across much of northern Japan from Thursday into Friday; however, Hokkaido will be largely spared with any rainfall limited to far southern parts of the island.

Travel disruptions are also possible, especially in areas that experience heavy rainfall around peak travel times.

Rough seas will be a concern for the southern and eastern coastline of Japan into Friday.

Another round of heavy rainfall is possible across South Korea and Japan this weekend as a storm arrives from China.

This heavy rainfall on top of the rain expected this week will bring an elevated risk for flooding and continue the threat of mudslides.

While the Philippines are forecast to avoid any direct impacts from this tropical system, moisture will be pulled across the country as the storm tracks northward and brings rounds of downpours to the country into this weekend.

The downpours will be most common in central and northern parts of the Philippines with western Luzon at greatest risk for flooding, mudslides and travel disruptions.

Hurricane Center Monitoring 4 Waves In Atlantic; Tropical Storm Alvin Holding Steady

The National Hurricane Center is monitoring four tropical waves in the Atlantic basin and a tropical storm in the Pacific.

Pacific – Location: 535 miles south-southwest of the southern tip of Baja California; Maximum sustained winds: 60 mph ; Movement: west-northwest at 14 mph; Next advisory: 5 a.m.

At 11 a.m., the center of Tropical Storm Alvin was 535 miles south-southwest of the southern tip of Baja California.

Alvin is moving toward the west-northwest near 14 mph. This general motion is expected to continue for the next day or so.

A turn toward the west is expected by late Saturday.

Maximum sustained winds are near 60 mph, with higher gusts.

Some strengthening is possible during the next 24 hours. Weakening is expected to begin Friday, and Alvin is forecast to become a remnant low Saturday.

Tropical-storm-force winds extend outward up to 25 miles from the center.

Atlantic

There are four tropical waves in the Atlantic basin today, according to NASA’s hurricane web page.

One is in the eastern Atlantic, one in Central Atlantic, and two are in the Caribbean Sea.

Satellite images continue to show dust blowing off Africa’s western coast.

No tropical disturbances are expected in the next 48 hours.

Dry air is surrounding the tropical wave in the eastern Caribbean, limiting development, according to the National Hurricane Center.

The waves in the western Caribbean may have contributed to strong to gale-force winds over the Central Caribbean overnight, the Hurricane Center said.

Study Reveals Key Factor In Himalayan Earthquake Rupture

The Himalayan orogenic belt produces frequent large earthquakes that impact population centers for a distance of over 2500 km. In the central region, the 2015 Gorkha earthquake in Nepal, with moment magnitude (MW) 7.8, partially ruptured a ~120-km by 80-km patch of the Main Himalayan Thrust (MHT), the detachment that separates the underthrusting Indian plate from the overriding Himalayan orogeny.

The rupture highlights important scientific questions about Himalayan formation and seismic hazards. These questions include how to distinguish between different possible geometries of the MHT, and how to better define the structural causes and locations of rupture segmentation both across-strike and along-strike in the orogenic belt.

A study led by Prof. BAI Ling from the Institute of Tibetan Plateau Research (ITP) of the Chinese Academy of Sciences revealed that the rupture length of the 2015 MW 7.8 Gorkha earthquake was likely controlled by spatial (both along- and across-strike) variations in the Main Himalayan Thrust.

The researchers combined seismic waveforms from several different deployments, including 22 seismic stations ITP had deployed along the China-Nepal border with an average elevation of 4.5 km prior to the earthquake. Using arrival times and waveform modeling, they determined source parameters of earthquakes, velocity structures and discontinuity topography in and around the source area.

The study showed that the MHT exhibited clear lateral variation along the geologic strike, with the Lesser Himalayan ramp having moderate dip on the MHT beneath the mainshock area, and a flatter and deeper MHT beneath the eastern end of the aftershock zone.

Following these observations, the impetus now is to image the entire 2,500-km Himalayan front to determine the morphology of the MHT and the likely controls on the maximum magnitude of rupture that can be accommodated in different parts of this convergence zone.

The study, entitled “Lateral variation of the Main Himalayan Thrust controls the rupture length of the 2015 Gorkha earthquake in Nepal,” was published in Science Advances.

NASA Captures Spectacular Images Of Raikoke Volcano Spewing Ash Into The Atmosphere After Huge Eruption

An astronaut aboard the International Space Station has captured a spectacular image of a volcano with a 2,300ft-wide crater spewing ash into the atmosphere after a powerful eruption.

The Raikoke Volcano—located on an island in the northwestern Pacific’s Kuril archipelago—has been dormant for roughly a century. But this quiet period came to an abrupt end in the early morning of June 22, when Raikoke blew its top sending a vast ash plume up to 8 miles into the sky, according to the Volcanic Ash Advisories Center (VAAC).

In the picture, you can clearly see how the cloud rises up in a narrow column before coming to a stop when it meets air of similar density.

“What a spectacular image. It reminds me of the classic Sarychev Peak astronaut photograph of an eruption in the Kurils from about ten years ago,” Simon Carn, a volcanologist at Michigan Tech, said in a NASA statement.

“The ring of white puffy clouds at the base of the column might be a sign of ambient air being drawn into the column and the condensation of water vapor,” he said. “Or it could be a rising plume from interaction between magma and seawater because Raikoke is a small island and flows likely entered the water.”

Much of the plume is now drifting eastwards over the Bering Sea and authorities are warning aircraft in the region to be careful of volcanic ash. This could pose a danger to aircraft because it contains small pieces of rock and volcanic glass.

Satellite data also indicates that the eruption has spewed out large quantities of gas, namely sulfur dioxide, which may have reached into the stratosphere—the second main layer of Earth’s atmosphere which starts between 4.3 and 12 miles high depending on the location above the planet.

“Radiosonde data from the region suggest that the eruption cloud is mostly in the stratosphere,” Can said. “The persistence of large sulfur dioxide amounts over the last two days also indicates stratospheric injection.”

It is important to closely monitor ash plumes that reach the stratosphere because they have the capacity to stay in the atmosphere for much longer than those which stop at lower altitudes.

Mapping Dark Energy – Accelerating the Expansion of the Universe

On 21 June 2019 the Spektrum-Röntgen-Gamma (Spektr-RG / SRG) spacecraft will be launched from the Kazakh steppe, marking the start of an exciting journey. SRG will be carrying the German Extended ROentgen Survey with an Imaging Telescope Array (eROSITA) X-ray telescope and its Russian ART-XC partner instrument. A Proton rocket will carry the spacecraft from the Baikonur Cosmodrome towards its destination – the second Lagrange point of the Sun-Earth system, L2, which is 1.5 million kilometers from Earth.

In orbit around this equilibrium point, eROSITA will embark upon the largest-ever survey of the hot universe. The space telescope will use its seven X-ray detectors to observe the entire sky and search for and map hot sources such as galaxy clusters, active black holes, supernova remnants, X-ray binaries and neutron stars.

Walther Pelzer, executive board member for the Space Administration at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR), says, “eROSITA’s X-ray ‘eyes’ are the best that have ever been launched as part of a space telescope. Their unique combination of light-collecting area, field-of-view and resolution makes them approximately 20 times more sensitive than the ROSAT telescope that flew to space in the 1990s. ROSAT also incorporated advanced technology that was ‘made in Germany’. With its enhanced capabilities, eROSITA will help researchers gain a better understanding of the structure and development of the universe, and also contribute towards investigations into the mystery of dark energy.”

The universe has been expanding continuously since the Big Bang. Until the 1990s, it was thought that this cosmic expansion would slow down and eventually come to a halt. Then, the astrophysicists Saul Perlmutter, Adam Riess and Brian Schmidt observed stellar explosions that were visible from a great distance and always emitted the same amount of light. They measured their distances and could hardly believe their findings.

“The Type 1a supernovae observed exhibited lower brightness levels than expected. It was clear that the universe was not slowing down as it expanded – quite the opposite, in fact. It is gathering speed and its components are being driven further and further apart at an ever-increasing rate,” explains Thomas Mernik, eROSITA Project Manager at the DLR Space Administration. With this discovery, the three researchers turned science upside and were awarded the Nobel Prize in Physics in 2011. Yet Perlmutter, Riess and Schmidt have left us with one crucial question: “What is the ‘cosmic fuel’ that powers the expansion of the universe? Since no one has yet been able to answer this question, and the ingredients of this catalyst are unknown, it is simply referred to as dark energy. eROSITA will now attempt to track down the cause of this acceleration,” explains Mernik.

Galaxy clusters – a key to dark energy

Very little is known about the universe. The ingredients that make up 4 percent of its energy density – ‘normal’ material such as protons and neutrons – is only a very small part of the ‘universe recipe’. What the other 96 percent is composed of remains a mystery. Today it is believed that 26 percent is dark matter. However, the largest share, estimated at 70 percent, is comprised of dark energy.

To track this down, scientists must observe something unimaginably large and extremely hot: “Galaxy clusters are composed of up to several thousand galaxies that move at different velocities within a common gravitational field. Inside, these strange structures are permeated by a thin, extremely hot gas that can be observed through its X-ray emissions. This is where eROSITA’s X-ray ‘eyes’ come into play. They allow us to observe galaxy clusters and see how they move in the universe, and above all, how fast they are travelling. We hope that this motion will tell us more about dark energy,” explains Thomas Mernik.

Scientists are not just interested in the movement patterns of galaxy clusters. They also want to count and map these structures. Up to 10,000 such clusters should be ‘captured’ by eROSITA’s X-ray ‘eyes’ – more than have ever been observed before. In addition, other hot phenomena such as active galactic nuclei, supernova remnants, X-ray binaries and neutron stars will be observed and identified.

eROSITA will scan the entire sky every six months for this purpose, and create a deep and detailed X-ray map of the universe over four years. It will thus produce the largest-ever cosmic catalog of hot objects and thus improve the scientific understanding of the structure and development of the universe.

The German telescope consists of two core components – its optics and the associated detectors. The former consists of seven mirror modules aligned in parallel. Each module has a diameter of 36 centimeters and consists of 54 nested mirror shells, whose surface is composed of a para-boloid and a hyper-boloid (Wolter-I optics).

“The mirror modules collect high-energy photons and focus them onto the CCD X-ray cameras, which were specially developed for eROSITA at our semiconductor laboratory in Garching. These form the second core component of eROSITA and are located at the focus of each of the mirror systems. The highly sensitive cameras are the best of their kind and, together with the mirror modules, form an X-ray telescope featuring an unrivaled combination of light-collecting area and field-of-view,” explains Peter Predehl, eROSITA principal investigator at MPE.