Here’s the full quote, as delivered by NASA Chief scientist Ellen Stofan at Tuesday’s panel discussion on the Agency’s search for habitable worlds and alien life:
“I think we’re going to have strong indications of life beyond Earth within a decade, and I think we’re going to have definitive evidence within 20 to 30 years.
We know where to look. We know how to look,” Stofan added. “In most cases we have the technology, and we’re on a path to implementing it. And so I think we’re definitely on the road.”
Former astronaut John Grunsfeld, associate administrator for NASA’s Science Mission Directorate, echoed Stofan’s assessment. “I think we’re one generation away in our solar system, whether it’s on an icy moon or on Mars, and one generation [away] on a planet around a nearby star.”
Maybe it’s time to start placing bets. Personally, my money’s on Europa – but each of the following “ocean worlds” listed in this infographic from NASA a solid candidate:
One thing all solid bodies in the Solar System share in common is craters. Some worlds, like Mercury or the Moon, are covered in them, having no atmosphere to erode them away. Earth has relatively few; our dynamic atmosphere and water circulation wipes them out after a few millennia. And some icy bodies like Saturn’s moon Enceladus or Jupiter’s Europa only have a few because their surfaces are also constantly changing… on a geologic timescale.
Source : Sen Blog
Image of Saturn Taken by Cassini Space Probe (Click Image to Download)
NASA’s Cassini spacecraft has been studying Saturn and its moons for a decade now, routinely delivering stunning images of the second largest planet in our solar system. One of its noteworthy achievements is that it is now shedding a lot more light on six moons that were once shrouded in mystery.
When NASA’s Voyager spacecraft flew by moons like Mimas, Enceladus, Tethys, Dione, Rhea, and Iapetus back in the 1980s, it sent back landmark images that were nevertheless fuzzy, incomplete, and hard to make out. Now, Cassini has plugged the holes – with bursts of color, no less – and delivered stunning new images of these icy satellites.
Here is a before/after shot of Mimas showcasing the differences between Voyager’s image (left) and Cassini’s (right).
“The most obvious [discoveries] are differences in color and brightness between the two hemispheres of Tethys, Dione and Rhea,” wrote Preston Dyches of NASA’s Jet Propulsion Laboratory. “The dark reddish colors on the moons’ trailing hemispheres are due to alteration by charged particles and radiation in Saturn’s magnetosphere.”
“Except for Mimas and Iapetus, the blander leading hemispheres of these moons – that is, the sides that always face forward as the moons orbit Saturn – are all coated with icy dust from Saturn’s E-ring, formed from tiny particles erupting from the south pole of Enceladus.”
You can view the rest of the images here. Impressively, however, these aren’t the only photographs of Saturn and its moons making headlines this week.
Source : RT.com