3.5bn years ago, a river used to run across Mars?

PTI | Jan 19, 2013, 06.28 AM IST

4

comments

0
inShare

Share More

A

A

READ MORE Water Sign On Mars|Water On Mars|European Space Agency|NASA

RELATED

• Kaatu Poochi is NASA now
• Student's Nasa visit hits visa roadblock
• First Indian film shot in NASA
• Nasa photo error puts Everest in India
• Nasa to send new rover to Mars in 2020

LONDON: New astonishing pictures by theEuropean Space Agency have revealed a 1,500km long and 7km wide river that once ran across Mars. The agency's Mars Express imaged thestriking upper part of the remnants of Reull Vallis river on Mars with its high-resolution stereo camera, ESA said. 

Reull Vallis, is believed to have formed when running water flowed in the distant martian past, cutting a channel through the Promethei Terra Highlands before running on towards the floor of the vast Hellas basin. This structure, which stretches for almost 1,500 km, is flanked by numerous tributaries , one of which can be clearly seen cutting in to the main valley towards the upper (north) side. 

The images show a region of Reull Vallis where the channel is 7 km wide and 300 m deep. The sides of Reull Vallis are sharp and steep. These structures are believed to be caused by the passage of loose debris and ice during the "Amazonian" period due to glacial flow along the channel. They were formed after it was originally carved by liquid water during the Hesperian period, which may have ended 3.5bn to 1.8bn years ago. PTI 

Nasa beams Mona Lisa to Moon with laser 

In a major advance in laser communication, Nasa scientists have beamed a picture of Leonardo da Vinci's masterpiece, Mona Lisa, to a powerful spacecraft orbiting the Moon. The first laser signal carrying the iconic image, fired from an installation in Maryland, beamed the Mona Lisa to the Moon to be received 384,400 km away by Nasa's Lunar Reconnaissance Orbiter (LRO), which has been orbiting the Moon since 2009. 

The Mona Lisa transmission is a major advance in laser communication for interplanetary spacecraft, Nasa scientists said. By transmitting the image piggyback on laser pulses, the team achieved simultaneous laser communication and tracking. The success of the laser transmission was verified by returning the image to Earth using the spacecraft's radio telemetry system. 

"This is the first time anyone has achieved one-way laser communication at planetary distances," said Lunar Orbiter Laser Altimeter, LOLA's principal investigator , David Smith of theMassachusetts Institute of Technology.