Cassini directly samples the plumes from Enceladus and finds an ocean-like Spray

Cassini has directly sampled the plumes from Enceladus and discovered a salty ocean-like spray.

The new paper analyzes three Enceladus flybys in 2008 and 2009 with the same instrument, focusing on the composition of freshly ejected plume grains. The icy particles hit the detector target at speeds between 15,000 and 39,000 mph (23,000 and 63,000 kilometers per hour), vaporizing instantly. Electrical fields inside the cosmic dust analyzer separated the various constituents of the impact cloud.

The data suggest a layer of water between the moon’s rocky core and its icy mantle, possibly as deep as about 50 miles (80 kilometers) beneath the surface. As this water washes against the rocks, it dissolves salt compounds and rises through fractures in the overlying ice to form reserves nearer the surface. If the outermost layer cracks open, the decrease in pressure from these reserves to space causes a plume to shoot out. Roughly 400 pounds (200 kilograms) of water vapor is lost every second in the plumes, with smaller amounts being lost as ice grains. The team calculates the water reserves must have large evaporating surfaces, or they would freeze easily and stop the plumes.

Unmanned sail prototype prepares for launch

A prototype of an unmanned sailing ship will begin a test voyage this fall.

Although Harbor Wing will operate without a captain and crew by sailing on a pre-programmed course, “the man is always in the loop,” Ott said. An operator, seated at a computer that could be hundreds of miles away, can control the craft with keystrokes that relay commands via satellite. The transmission gap, from order to receipt, is only 18 seconds, which “on the open ocean is not much,” he said, “so you have very close control.”

NASA about to decide on its shuttle heavy-lift replacement

NASA is about to decide on its shuttle heavy-lift replacement, and it looks like it will be almost entirely shuttle-derived.

As I have said previously, this rocket will almost certainly never fly. NASA has to start over after spending billions and years developing Constellation, and is being given less money and time to do it.

And even if I am wrong and this rocket does fly, I bet it will do only one flight and then be retired as too costly.

ESA controllers buy time to solve problems on comet probe Rosetta

This ain’t good. One of the reasons ESA controllers recently put the comet probe Rosetta into hibernation for two and a half years was in order to buy time to solve a serious technical problem.

Mission managers said the hibernation will permit Rosetta to rest its four reaction wheels, two of which have shown signs of degradation. The satellite needs three to function, and one of the two problem wheels will be used only as a spare when the satellite is awakened in January 2014 in preparation for its approach to a comet.

Second X-51 hypersonic flight crashes prematurely

Second X-51 hypersonic flight crashes prematurely.

After what the US Air Force described as a ‘flawless’ flight to the launch point aboard a Boeing B-52 mothership, the X-51 was successfully boosted to Mach 5.0 by a rocket booster. The Pratt & Whitney Rocketdyne scramjet engine successfully ignited using its initial fuel, ethylene. During the immediate transition to JP-7, the conventional fuel that makes the X-51 unique, an inlet unstart occurred. A subsequent attempt to restart and reorient to optimal conditions was unsuccessful.

Robot refueling test of satellites to be launched on last shuttle flight

A testbed for testing the robotic refueling of satellites will be installed on ISS on last shuttle flight.

This whole testbed is the brainchild of Frank Cepollina, the man behind all of the Hubble Space Telescope repair missions. Until recently it was doubtful there was room for this project on any shuttle mission. That he nonetheless managed to get it on the last flight is another testament to Cepollina’s incredible ability to get things done. And if the tests work on ISS, NASA will then consider launching operational systems for refueling several perfectly usable climate satellites now in orbit.

Human bones taken to ISS for long space flight experiments.

Human bones were part of the cargo on board the Soyuz capsule launched to ISS today.

“The fragments of human bones will be used to study the causes and dynamics of decalcination of bone tissue in a long space flight,” the head of the experiment, Tatiana Krasheninnikova told Itar-Tass. The problem of decalcination is a headache for medics responsible for spacemen’s health. Researches in this area are conducted by scientists from many ISS member states. However it is impossible to take sample of spacemen’s bones, only their urine is being examined, and a complete picture of dynamics of changes in human bones is not clear, she noted.

1 487 488 489 490 491 511