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Strong and shallow M6.6 earthquake hits Andreanof Islands, Alaska
A strong and shallow earthquake registered by the USGS as M6.6 hit the Andreanof Islands, Aleutian Islands, Alaska at 21:57 UTC on August 15, 2018. The agency is reporting a depth of 31.6 km (19.6 miles). EMSC is reporting M6.6 at a depth of 40 km (24.8 miles). According to the USGS, the epicenter was located 41 km (25 miles) S of Tanaga volcano, 108 km (67 miles) WSW of Adak (population 332), Alaska and 1 477 km (918 miles) ESE of Klyuchi (population 10 000), Russia. There are no people living within 100 km (62 miles). Based on all available data, there is no tsunami threat from this earthquake, PTWC said. The USGS issued a green alert for shaking-related fatalities and economic losses. There is a low likelihood of casualties and damage. Overall, the population in this region resides in structures that are resistant to earthquake shaking, though vulnerable structures exist. The predominant vulnerable building types are…

Rapidly intensifying, possibly planet-wide dust storm affecting Mars

Rapidly intensifying, possibly planet-wide dust storm affecting Mars

A massive and intensifying dust storm, one of the most intense ever observed on Mars, is affecting the Red Planed since May 30, 2018. The storm is growing rapidly and is likely to go, or has already gone, global.
On June 10, the storm covered more than 41 million km2 (15.8 million mi2), according to NASA's JPL. This is about the area of North America and Russia combined or more than a quarter of the surface of Mars.
However, due to its rapid intensification, some astronomers say the dust storm is likely to go, or has already gone, global.
2018 Mars dust storm June 2018
Image courtesy Mark Justice, Melbourne, Australia
It has blocked out so much sunlight, it has effectively turned day into night for NASA's Opportunity rover, which is located near the center of the storm, inside Mars' Perseverance Valley. As a result, Opportunity's power levels have dropped significantly by June 6, requiring it to shift to minimal operations and temporarily cease science operations.
NASA engineers attempted to contact the Opportunity on June 12 but did not hear back from the nearly 15-year old rover. The team is now operating under the assumption that the charge in Opportunity's batteries has dipped below 24 volts and the rover has entered low power fault mode, a condition where all subsystems, except a mission clock, are turned off. The rover's mission clock is programmed to wake the computer so it can check power levels.
If the rover's computer determines that its batteries don't have enough charge, it will again put itself back to sleep.
Due to an extreme amount of dust over Perseverance Valley, mission engineers believe it is unlikely the rover has enough sunlight to charge back up for at least the next several days.
On June 10, the storm's atmospheric opacity, the veil of dust blowing around, which can blot out sunlight, was already much worse than a 2007 storm that Opportunity survived and continued its operations after two weeks. The previous storm had an opacity level, or tau, somewhere above 5.5; this new storm had an estimated tau of 10.8 as of Sunday morning, June 10. 
To discuss this unprecedented event, NASA will host a media teleconference at 17:30 UTC (10:30 PDT, 13:30 EDT, 23:30 AEST).
Participants in the teleconference will include:
  • John Callas, Opportunity project manager at NASA's Jet Propulsion Laboratory, Pasadena, California
  • Rich Zurek, Mars Program Office chief scientist at JPL
  • Jim Watzin, director of the Mars Exploration Program at NASA Headquarters, Washington
  • Dave Lavery, program executive at NASA Headquarters for the Opportunity and Curiosity rovers
Featured image courtesy Mark Justice, Australia

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