Showing posts with label Hits. Show all posts
Showing posts with label Hits. Show all posts

Monday, November 11, 2013

India's Ambitious MARS Mission hits a major snag

India's mission to Mars has hit a snag, after a planned engine burn failed to raise the spacecraft's orbit around Earth by the intended amount.

The problem occurred during a manoeuvre designed to boost the craft's maximum distance from 71,623km to 100,000km.

A problem with the liquid fuel thruster caused the 1,350kg vehicle to fall short of the mark.

But the head of the Indian Space Research Organisation (Isro) said the spacecraft remained "healthy".

As a solution, the Mars Orbiter Mission (MOM) - known informally as Mangalyaan, or Mars-craft - will be commanded to execute an additional thruster firing at 05:00 IST on Tuesday (23:30 GMT on Monday) to make up for the shortfall.

However, independent experts cont acted by the BBC said they were puzzled by Isro's working hypothesis for the failure.

Instead of flying directly to Mars, the probe is scheduled to orbit Earth until the end of the month, building up the necessary velocity to break free from our planet's gravitational pull.

This was the fourth in a series of five engine burns known as "midnight manoeuvres" because several constraints require that they are carried out in the early hours of the morning.

Speaking to Pallava Bagla, science editor at Indian broadcasting network NDTV, Isro's chairman K Radhakrishnan said: "The spacecraft is healthy and it encountered a problem when a specific redundancy test was being conducted and it failed to reach the desired velocity it was to achieve."

In that redundancy test, two coils in the liquid engine were supposed to be energised simultaneously.

"When you are going so far away, if one thing fails, you want to have a standby option. Everything is almost doubled up on the satellite, which is why they were not able to carry so much scientific equipment," Mr Bagla explained.

Saturday, May 4, 2013

US Air Force's Experimental Waverider Scramjet hits Mach 5.1 (3,880 mph)


The final flight of the X-51A Waverider test program saw the Scramjet aircraft reach Mach 5.1 over the Pacific Ocean, the U.S. Air Force said Friday.

The unmanned hypersonic researcher craft traveled more than 230 nautical miles in just over 6 minutes Wednesday over the Point Mugu Naval Air Warfare Center Sea Range off California before crashing into the ocean as intended, an Air Force release said.

The X-51A took off from Edwards Air Force Base in California under the wing of a B-52H Stratofortress before being released at about 50,000 feet.

A solid rocket booster took the X-51A to about Mach 4.8 at which point the craft's scramjet engine ignited and accelerated it to Mach 5.1 - about 3,880 miles per hour - at 60,000 feet.

Scramjet stands for supersonic combustion ram jet, which has no moving parts; fuel is mixed with air rushing into the combustion chamber at supersonic speeds and then ignited.

"It was a full mission success," Charlie Brink, X-51A program manager for the Air Force Research Laboratory
, said in a statement.

"I believe all we have learned from the X-51A Waverider will serve as the bedrock for future hypersonics research and ultimately the practical application of hypersonic flight."

Tuesday, March 19, 2013

NASA Mars Curiosity Rover Hits New Snag

The location of a rock target called "Knorr" is indicated on this self-portrait of the Curiosity rover in the "Yellowknife Bay" area. 

This self-portrait is a mosaic of images taken by Curiosity's Mars Hand Lens Imager (MAHLI) camera during the 177th Martian day, or sol, of Curiosity's work on Mars (Feb. 3, 2013). 

CREDIT: NASA/JPL-Caltech/MSSS

A new glitch on NASA's Mars rover Curiosity has forced the vehicle to stay in safe mode longer than planned, stalling science operations for another couple of days, scientists said today (March 18).

The Curiosity rover had paused in its scientific investigation of the Red Planet in late February, when corrupted memory files forced engineers to switch the rover's main operations from its "A-side" computer to its "B-side" backup.

Just as the computer switch was sorted out, though, mission managers decided to put the rover back in standby mode on March 5 to protect it from possible radiation that could be released by a major solar flare pointed toward Mars.

Curiosity had come out of safe mode following that scare, but normal science operations had not yet resumed.

Now, a computer file error has forced the rover into safe mode again.

"This is not something which is rare or extraordinary,"Curiosity chief scientist John Grotzinger said today at the Lunar and Planetary Science Conference in The Woodlands, Texas. "It does mean that science has to stand down for a couple more days."

The latest issue has to do with some of the rover's files that were scheduled for deletion. One of those files was connected to a file still in use by the spacecraft, so the deletion process prompted an error that sent the rover into safe mode again, preventing the rover from resuming science as planned.

"If not for the latest safing, we would have been back in action today," Grotzinger said. "The expectation is, it's going to take a couple of sols [Martian days] to resolve this one."

Despite these technical setbacks, though, Curiosity's team of scientists has been forging ahead with analysis of the wealth of data collected by the rover so far. Those measurements allowed the researchers to declare last week the mission had found proof that a spot on ancient Mars would have provided habitable conditions to microbes, had they been present during the planet's past.

Tuesday, January 26, 2010

NASA: Avoiding Planetary Asteroid Hits Is A Big Job

Avoiding Planetary Hits Is A Big Job

The Scope of the Hazard
Near-Earth objects are asteroids and comets that orbit the Sun and approach or cross Earth's orbit. An asteroid or comet about 10 kilometers in diameter struck the Yucatan peninsula 65 million years ago and caused global devastation, probably wiping out large numbers of plant and animal species including the dinosaurs. Objects as large as this one strike Earth only about once every 100 million years on average, the report notes.

NASA has been highly successful at detecting and tracking objects 1 kilometer in diameter or larger, and continues to search for these large objects. Objects down to sizes of about 140 meters in diameter - which NASA has been mandated to survey for - would cause regional damage; such impacts happen on average every 30,000 years, the report says.

While impacts by large NEOs are rare, a single impact could inflict extreme damage, raising the classic problem of how to confront a possibility that is both very rare and very important. Far more likely are those impacts that cause only moderate damage and few fatalities.

Conducting surveys for NEOs and detailed studies of ways to mitigate collisions is best viewed as a form of insurance, the report says. How much to spend on these insurance premiums is a decision that must be made by the nation's policymakers.