Month: March 2016

An "approximately" true color image of Ceres taken by the Dawn spacecraft as it approached the dwarf planet in May, 2015. (credit: NASA)

THE WOODLANDS, Texas—Ceres is a cold, dead world today. But it wasn't always so, and as researchers delve deeper into images and data collected by the Dawn spacecraft, they continue to find intriguing hints about a world that likely had a large, subsurface ocean during the early days of the solar system. They also have found a number of features on the surface of Ceres they cannot yet explain, deepening the mystery of the dwarf planet’s evolution.

The largest object in the asteroid belt, measuring some 950km across, Ceres is roughly the size of Texas. So perhaps it's fitting that scientists gave their most detailed briefing yet about the planet in a darkened conference room in The Woodlands, just north of Houston, at the Lunar and Planetary Science Conference on Tuesday. Here the mysterious bright spots of Occator crater and other parts of the small world shone brightly.

These parts also intrigued. As the Dawn spacecraft approached Ceres in 2015, it revealed a large bright spot in Occator crater, but as the spacecraft has flown down to within 400km of the world’s surface and produced a global map at a resolution of 35 meters per pixel, scientists have found many bright spots in the crater likely due to salt deposits. Still, the brightest one at the center remains most interesting.

(credit: Tesla, Green Mountain Power)

Tesla has decided that it won’t be making the 10kWh stationary storage batteries it unveiled last April, instead focusing exclusively on the 7kWh version.

The 10kWh version of Tesla’s Powerwall was made to be used as backup storage only—its nickel-cobalt chemistry limited the user to cycling the battery 500 times, so daily use was out of the question. The 7kWh battery, on the other hand, is made to integrate with solar panels, and due to its nickel-manganese chemistry, Tesla said it could be cycled 5,000 times.

After Tesla quietly removed the option for a 10kWh battery on its website, the company confirmed in an e-mail to Greentech Media that the larger version had been discontinued. "The Daily Powerwall supports daily use applications like solar self-consumption plus backup power applications, and can offer backup simply by modifying the way it is installed in a home," the e-mail read. "Due to the interest, we have decided to focus entirely on building and deploying the 7kWh Daily Powerwall at this time."