Curiosity rover finds old Martian streambed

LOS ANGELES — The NASA rover Curiosity has beamed back pictures of bedrock that suggest a fast-moving stream, possibly waist-deep, once flowed on Mars — a find that the mission’s chief scientist called exciting.

There have been previous signs that water existed on the red planet long ago, but the images released Thursday showing pebbles rounded off, likely by water, offered the most convincing evidence so far of an ancient streambed.

There was “a vigorous flow on the surface of Mars,” said chief scientist John Grotzinger of the California Institute of Technology. “We’re really excited about this.”

The discovery did not come as a complete surprise. NASA decided to plunk Curiosity down inside Gale Crater near the Martian equator because photos from space hinted that the spot possessed a watery past. The six-wheeled rover safely landed Aug. 5 after a nail-biting plunge through the Martian atmosphere. It’s on a two-year, $2.5 billion mission to study whether the Martian environment could have been favorable for microbial life.

Present day Mars is a frozen desert with no hint of water on its radiation-scarred surface, but geological studies of rocks by previous missions suggest the planet was warmer and wetter once upon a time.

The latest evidence came from photos that Curiosity took revealing rounded pebbles and gravel — a sign that the rocks were transported long distances by water and smoothed out.

The size of the rocks — ranging from a sand grain to a golf ball — indicates that they could not have been carried by wind, said mission scientist Rebecca Williams of the Planetary Science Institute in Tucson, Ariz.

Though Curiosity did not use its high-tech instruments to drill into the rocks or analyze their chemical makeup, Grotzinger said scientists were sure that water played a role based on just studying the pictures.

It’s unclear how long the water persisted on the surface, but it easily could have lasted “thousands to millions of years,” said mission scientist Bill Dietrich of the University of California, Berkeley.

Curiosity chanced upon the dried-up streambed while driving to Glenelg, an intriguing spot where three types of terrain meet. Its ultimate destination is Mount Sharp, a mountain rising from the center of crater floor, but it was not expected to travel there until the end of the year.

Finding past water is a first step toward learning whether the environment could have supported microbes. Scientists generally agree that besides water and an energy source such as the sun, organic carbon is a necessary prerequisite for life.

While an ancient streambed holds promise as a potentially habitable environment, scientists don’t think it’s a good place to preserve the carbon building blocks of life. That’s why the rover will continue its trek to the foothills of Mount Sharp where there’s a better chance of finding organics.

More in Local News

Shock from WSU suicide ripples through Snohomish County

Roughly 1 in 10 seniors, sophomores and 8th-graders said they had attempted to take their own lives.

New leaders coming to county, state political parties

Hillary Moralez of Bothell takes over as chair for the Snohomish County Democratic Party.

Mom and brother turn in suspect in Stanwood robberies

The man is suspected of robbing the same gas station twice, and apologizing to the clerk afterward.

$1,000 reward for info on who killed an eagle near Snohomish

After being shot, the raptor was treated at the Sarvey Wildlife Center but died overnight.

Possible bobcat sighting keeps Snohomish students inside

The creature was spotted on the campus of Valley View Middle School around noon.

Derrick “Wiz” Crawford, 22, is a suspect in the homicide of his roommate. (Edmonds Police Department)
Roommate suspected in Edmonds killing found hiding in closet

Police had been searching for him for 10 days before locating him at a house in Everett.

Stabbing in Everett follows dispute between brothers-in-law

The victim, 54, was hospitalized. The suspect, 29, had not been apprehended Thursday.

Camano Island man gets 18 years for role in drug ring

He was convicted of helping lead a drug distribution network in four Washington counties.

Lake Stevens man missing since beginning of January

Jason Michael Knox White hasn’t used his credit card or withdrawn money from his bank since then.

Most Read