Month: August 2018

Russian Volcano Filmed Spewing Out Enormous Ash Clouds

A helicopter tour guide filmed incredible high-definition aerial footage of a Russian volcano as it spewed plumes of ash into the sky. The eruption was so severe that a Volcanic Ash Advisory has been issued for the region.

The Karymsky Volcano in Kamchatka, eastern Russia, is one of the most active volcanoes in the region – which is home to more than 100 active volcanoes. Local tour guide Aleksandr Ostrowski, 27, said he filmed the eruption while flying to the Valley of Geysers via helicopter.

Plumes of ash from the volcano have spread for about 92 km according to the Kamchatka Volcanic Eruption Response Team (KVERT), who have categorized Karymsky’s current state as orange, meaning “erupting or restless”.

Ash eruptions of up to 19,700 feet (6km) could occur “at any time”, KVERT warns, which is likely to have an affect on low-flying aircrafts. Previous eruptions from Karymsky have been described as ‘vulcanian’. Such eruptions can involve large metre-size rocks being thrown several kilometers into the air, and usually end with a flow of viscous lava.

Ongoing Kilauea Volcano Eruption Sets Record

Hawaii’s Kilauea volcano has been erupting since May 3, and now the eruption has set a local record.

It’s now the longest eruption ever in the lower east rift zone.

The previous record was set in 1955.

During that eruption, at least 24 different vents opened along a nine-mile stretch.

24 vents have also opened during the current eruption. Only one vent is active right now.

Officials with the Hawaiian Volcano Observatory say there’s no indication that the current eruption will end any time soon.

Brown Dwarf In A Dynamical-Tide Regime Detected By WASP Survey

European astronomers have discovered a new transiting brown dwarf in a dynamical-tide regime as part of the Wide Angle Search for Planets (WASP) survey. The newly found object, designated WASP-128b, orbits its host on a close orbit—the measured stellar rotation rate places it in a regime where tidal interaction is dominated by dynamical tides.

Brown dwarfs are intermediate objects between planets and stars. Astronomers generally agree that they are substellar objects occupying the mass range between 13 and 80 Jupiter masses. To date, most of discovered brown dwarfs were found to be solitary. However, some brown dwarfs orbit Sun-like stars, and notably, up to 16 percent of such stars have companions more massive than Jupiter, of which fewer than 1 percent are brown dwarfs.

Furthermore, only a handful of brown dwarfs were found to be orbiting G-type dwarfs. Such objects in G dwarf systems are thought to undergo rapid orbital decay due to runaway tidal dissipation. Expanding the list of known brown dwarfs in that kind of systems could be helpful in studying various substellar evolution models.

Recently, a team of astronomers led by Vedad Hodzic of the University of f Birmingham, U.K., has detected a new brown dwarf in a close orbit around a G dwarf under the WASP program. The transit signal in the light curve of the star WASP-128 was identified using the 0.6 m TRAPPIST robotic telescope and the 1.2 m Euler telescope, both located at ESO La Silla Observatory in Chile. Follow-up spectroscopic observations of this star confirmed that the signal was caused by a massive circumstellar companion orbiting the host.

“We report the discovery of WASP-128b, a new transiting brown dwarf discovered by the WASP survey, orbiting a G0V host on a close orbit, where the measured stellar rotation rate places the system well-within the dynamical-tide regime, suggesting strong tidal coupling between the pair,” the researchers wrote in the paper.

WASP-128b is about the size of Jupiter (0.94 Jupiter radii) but 37.5 times more massive than our solar system’s biggest planet. It orbits its parent star at a distance of approximately 0.036 AU, every 2.2 days.

Moreover, the researchers found that WASP-128b is mildly inflated and also calculated that its remaining lifetime is about 267 million years.

“While in the dynamically stable state, the infall time of WASP-128b is given by the magnetic braking timescale, and we derive a remaining lifetime of 267 Myr,” the paper reads.

The astronomers noted that this value is similar to that of some ultra-short period massive “hot Jupiter” exoplanets.

The host, located about 1,375 light years away from the Earth, is some 16 percent larger and more massive than the Sun. It has effective temperature of 5,950 K, an estimated age of about 2.3 billion years and a rotation period of around 2.93 days. As noted in the paper, such rotation rate is indicative of a tidal spin-up due to its massive companion.

What Makes Diamonds Blue? Boron From Oceanic Crustal Remnants In Earth’s Lower Mantle

Blue diamonds — like the world-famous Hope Diamond at the National Museum of Natural History — formed up to four times deeper in the Earth’s mantle than most other diamonds, according to new work published on the cover of Nature.

“These so-called type IIb diamonds are tremendously valuable, making them hard to get access to for scientific research purposes,” explained lead author Evan Smith of the Gemological Institute of America, adding, “and it is very rare to find one that contains inclusions, which are tiny mineral crystals trapped inside the diamond.”

Inclusions are remnants of the minerals from the rock in which the diamond crystallized and can tell scientists about the conditions under which it formed.

Type IIb diamonds owe their blue color to the element boron, an element that is mostly found on the Earth’s surface. But analysis of the trapped mineral grains in 46 blue diamonds examined over two years indicate that they crystallized in rocks that only exist under the extreme pressure and temperature conditions of the Earth’s lower mantle.

The research group — which included Carnegie’s Steven Shirey, Emma Bullock, and Jianhua Wang — determined that blue diamonds form at least as deep as the transition zone between the upper and lower mantle — or between 410 and 660 kilometers below the surface. Several of the samples even showed clear evidence that they came from deeper than 660 kilometers, meaning they originated in the lower mantle. By contrast, most other gem diamonds come up from between 150 and 200 kilometers.

So how did the boron get down there if it is an element known for residing predominately in the shallow crust?

According to the hypothesis put forth by the research group, it came from seafloor that was conveyed down into the Earth’s mantle when one tectonic plate slid beneath another — a process known as subduction.

The new study proposes that boron from the Earth’s surface was incorporated into water-rich minerals like serpentine, which crystallized during geochemical reactions between seawater and the rocks of the oceanic plate. This reaction between rock and water is a process called serpentinization and can extend deep into the seafloor, even into the oceanic plate’s mantle portion.

The group’s discovery reveals that the water-bearing minerals travel far deeper into the mantle than previously thought, which indicates the possibility of a super-deep hydrological cycle.

“Most previous studies of super-deep diamonds had been carried out on diamonds of low quality,” Shirey said. “But between our 2016 finding that the world’s biggest and most-valuable colorless diamonds formed from metallic liquid deep inside Earth’s mantle and this new discovery that blue diamonds also have super-deep origins, we now know that the finest gem-quality diamonds come from the farthest down in our planet.”