Space telescope that found new worlds probably lost (5/20/13)
After extending its 3.5-year mission by about six months, NASA's revolutionary Kepler space telescope is crippled and probably only has months to live.
Kepler has collected data leading to the stunning conclusion that there are potentially billions of Earth-like planets in our Milky Way galaxy. Kepler has discovered 132 planets that Earth-based telescopes have confirmed. There are 2,700 other Kepler planet discoveries awaiting confirmation.
The Goldilocks Principal underlies Kepler's mission: finding planets that are not only Earth-sized but also orbiting a Sun-like star in a "habitable zone." This orbital sweet spot is not too warm and not too cold; it's just right to support life.
With two of its four gyroscopes now inoperative, Kepler has enough fuel onboard to steady itself for about six months. The second "reaction wheel" broke last week, and Kepler's wobble is posing a daunting challenge to NASA engineers.
In a May 15 prepared statement, NASA reported: "With the failure of a second reaction wheel, it's unlikely the spacecraft will be able to return to the high pointing accuracy that enables its high precision (photo imaging)."
The following images are artists' conceptions of planets Kepler has observed:
Kepler-35b is a Saturn-sized planet orbiting two stars. /NASA image
Kepler-11 has a Sun-like star and six planets. /NASA image
Cassini spacecraft one of NASA's star robots (4/30/13)
The Cassini-Huygens mission and the Mars rovers are star performers in NASA's drive to explore the solar system with robotic technology. Cassini has been exploring Saturn and its moons since 2004, deploying the Huygens lander in 2005 for a successful touchdown on Saturn's surface and sending thousands of images back to Earth since.
Manned spaceflight has many allures, but robotic space missions will have far longer reach at far lower cost for the foreseeable future.
Killer asteroids: 'If it's coming in three weeks, pray' (3/20/13)
Scientists testifying before Congress on Tuesday said the effort to find small killer asteroids is behind schedule and there is little that could be done if a large asteroid capable of destroying civilization were detected a few weeks before it collided with Earth.
NASA is leading a global push to find and track these "near-Earth objects." The U.S. space agency is confident it has found 90 percent of near-Earth objects capable of wreaking the kind worldwide catastrophe that occurred 60 million years ago, when scientists believe a large asteroid strike wiped out the dinosaurs as well as thousands of other animal and plant species on the planet. But if there's a mile-wide asteroid bearing down on Earth now, we're apparently doomed.
"The answer to you is, if it’s coming in three weeks, pray," NASA Administrator Charles Bolden told the House Science, Space and Technology Committee.
The effort to find smaller killer asteroids such as the one that exploded over Russia last month and injured more than 1,200 people is behind schedule, Bolden and President Obama's top science adviser testified. "Unfortunately, the number of undetected potential 'city killers' is very large," John Holdren said. "It’s in the range of 10,000 or more."
Congress has directed NASA to find 90 percent of near-Earth objects that are at least as big as a football field by 2020. But Bolden said more money and a new space-based telescope are needed to reach that goal. At the current rate of funding, he said the effort to detect "city killer" asteroids is about 10 years behind schedule.
The B612 Foundation says several years of advanced warning would be required to launch a mission to deflect an approaching killer asteroid: "In general, to deflect an asteroid we would need several years to decades of advance notice. That is because the amount (of energy) you need to deflect an asteroid greatly increases the closer it is to hitting you. In addition, we need a suitable launch window that allows a spacecraft to reach the asteroid."
Curiosity hits hole-in-one in search for life on Mars (3/16/13)
The NASA Curiosity rover's first test drill hole in Martian rock last month apparently tapped an ancient lake bed. In an even more stunning discovery, the gray, clay-like rock bears traces of carbon that could be evidence of life from the Red Planet's disant past. /NASA images
A little luck sprinkled with a measure of NASA genius appears to have led to a major discovery on Mars.
In August, NASA's Curiosity rover landed close enough to a suspected ancient lake bed that mission leaders decided to take a detour away from their top objective, 14,000-foot-tall Mount Sharp, to collect a rock sample. In the Curiosity mission gameplan, the first use of the drill at the end of rover's robotic arm was planned to be only a test of the hardware and a "flushing" of the rover's rock dust collection and analysis system to make sure there was no contamination from Earth.
But photos of both the drill site and the rock dust collected from the drilling supported the lake bed theory, and an analysis of the rock dust was launched. Here are some excerpts from Curiosity chemistry instrumentation scientist David Blake's comments on NPR's Science Friday:
"We actually drove away from our primary destination, which is a place called Mount Sharp. It's a 5,000-meter, about 14,000-foot-tall, mountain in the middle of Gale Crater that has all these layered sediments from early Mars. So that's our ultimate destination. But it's about eight kilometers away. We kind of drove in the opposite direction because there was this real interesting area that many people on the team thought actually could be a lake bed. And so we're going to do one additional drill here to kind of make sure what we have and understand what it is, and then we'll take the long march to Mount Sharp. ...
"If we find (in the second drilling sample) what we think we've already found in the minerals, which tell us it's a habitable environment, and if the SAM instrument, which is a suite of instruments that do organic analyses, can find some organic compounds that clearly aren't from Earth, well, that would be a home run.
"And I'm not even suggesting it would be from organisms, just to know that there was carbon contained -- organic carbon -- contained inside this rock for three billion years that we could come there and analyze today."
NASA's Mars rover triumph for American ingenuity (2/18/13)
Reports of the death of American technological prowess have been greatly exaggerated.
After successfully executing the most complicated robotic landing on another planet in August, NASA's latest Mars mission is literally on a roll, with the Curiosity rover collecting a treasure trove of scientific information on the Red Planet. Curiosity has been transmitting stunning images of the Martian surface back to Earth for months, and the rover successfully completed a critically important first use of the drill at the end of its robotic arm about 10 days ago.
The images shown in this blog post show the potential for the Curiosity mission to revolutionize our understanding of the geologic history of Mars. And the rover appears to be on the right track to achieving the mission's grandest goal: determining whether life has ever existed on the Martian surface.
Curiosity reaches 'biggest milestone' since landing (2/17/13)
NASA's Curiosity rover on Mars passed the last major test of its equipment about a week ago, using the drill on its robotic arm for the first time.
In a prepared statement released Feb. 9, John Grunsfeld, associate administrator for NASA's Science Mission Directorate, hailed deployment of the drill as a key achievement. "The most advanced planetary robot ever designed is now a fully operating analytical laboratory on Mars," he said. "This is the biggest milestone accomplishment for the Curiosity team since the sky-crane landing last August."
After drilling a shallow test hole, Curiosity bored about 2.5 inches into a rock called "John Klein," which was named in honor of a rover team member who died in 2011. Rock powder collected during the drilling has been analyzed with sensors onboard NASA's six-wheeled robotic geologist, and scientists are working to interpret that data. The car-sized rover is trying to determine whether the Gale Crater on Mars ever had conditions suitable for sustaining life, including clues in Martian rocks that would indicate the presence of liquid water millions of years ago.
Rock powder Curiosity collects is analyzed with the rover's Chemical and Mineralogy instrument as well as its Sample Analysis at Mars instrument.
The CheMin instrument uses X-ray technology to produce data that is transmitted back to Earth for detailed analysis. It can take upto 10 hours for the instrument to process a sample.
The SAM instrument has three devices that analyze rock powder at the molecular level: a quadrupole mass spectrometer, a gas chromatograph and a tunable laser spectrometer. The quadrupole mass spectrometer and gas chromatograph are designed to detect organic compounds that could be the building blocks for Martian life. The tunable laser spectrometer is designed to analyze Martian carbon dioxide and to detect traces of methane. Many life forms on Earth produce carbon dioxide and methane.
Feb. 15 asteroid flyby should be global wakeup call (2/14/13)
When it comes to celestial objects striking the Earth, size definitely matters.
While the miles-wide asteroid that struck the planet 60 million years ago and wiped out the dinosaurs gets all the headlines, scientists believe smaller chunks of ice and rock are capable of leveling entire metropolitan areas. Earth likely will be spared an explosive encounter with asteroid 2012 DA14 tomorrow, but the planet apparently wasn't so lucky in 1908.
In what is widely known as the Tunguska Event, an asteroid or comet about the size of 2012 DA14, which is about as big as a cruise ship, entered the Earth's atmosphere on June 30, 1908, then exploded several miles above a remote area of Siberia. Millions of trees were flattened in the blast zone, which spanned an 830 square-mile area. The explosion, estimated to be more than 1,000 times more powerful than the atomic bomb dropped on Hiroshima in 1945, knocked people from their feet as far as 40 miles away.
Given the potential for such collisions to wreak cataclysmic destruction, you would think governments around the world would consider these so-called Near Earth Objects a top priority. “It’s like Mother Nature sending a warning shot across our bow,” Don Yeomans, a scientist at NASA's Jet Propulsion Laboratory, said of 2012 DA14 in The Washington Post last week.
It's easy to argue not enough is being done to track Near Earth Objects and to develop technology to alter their course if necessary to protect Earth. Scientists believe they have discovered 95 percent of Near Earth Objects capable of wiping out most terrestial life on the planet. But Near Earth Objects the size of 2012 DA14 are a different story.
"Saying we’re only going to find the civilization-killers is a (sub-par) threshold,” former U.S. astronaut Ed Lu told The Washington Post. “We can do better than that.”
Space-based telescopes revealing Sun's secrets (2/1/13)
NASA's $817 million Solar Dynamics Observatory has captured images of the Sun's coronal mass ejections, which have mystified scientists for decades. /NASA video via YouTube
With more than 99 percent of solar system's total mass, the Sun is a big story.
The Sun is essential to nearly all life-forms on Earth, but it can make life difficult for spacecraft and electrical grids during the peak of its 13-year coronal activity cycle, which is occurring now. The Sun's corona is the outer solar atmosphere, where solar flares cast radiation into space and coronal mass ejections can spew billions of tons of solar material into the cosmic abyss.
According to NASA, coronal mass ejections:
- draw their explosive energy from violent eruptions of gas and magnetic fields
- send solar materials to Earth in one to three days
- bombard spacecraft with charged particles, prompting the design of shielded safe areas for astronauts
- cause geomagnetic storms in the outer envelope of the Earth's magnetic field, which trigger colorful auroras in polar regions
- can damage or disrupt electrical grids
Search for extraterrestrial life advances (12/22/12)
The number of possible Earth-like planets is mounting, with each discovery increasing the likelihood of extraterrestrial life. Check out this report on Tau Ceti from NPR's Science Friday.
12/12/2012: Planet killer visits Earth
An odd coincidence?
Tons of ink have been spilled and megabytes of server space consumed over the 12/21/2012 prediction of doom in the Mayan calendar. Given the Mayans' sophisticated understanding of astronomy, could they have predicted for today a devastating collision of asteroid 4179 Toutatis and Earth?
Mayan math may have been off a few million miles, but the potential for a cataclysmic asteroid strike on Earth deserves more attention than it gets. Ironically, as various and sundry prognostications of Armageddon spark periodic media frenzies, the search for killer asteroids, from city busters to planet-scorching mountains of spaceborne rock and ice, goes on in the darkness outside the media spotlight.
Understanding the impact of asteroids on the evolution of Earth is a relatively fresh area of science. Speculation over the cause of the Moon's craters raged well into the middle of the 20th century, when geologist Gene Shoemaker solved the mystery at Meteor Crater in Arizona. In the 1950s, Shoemaker proved that the mile-wide, 550-feet-deep gash in the Arizona desert was the result of a meteor strike about 50,000 years ago. Subsequent research, including the Apollo missions to the Moon's surface, proved asteroid strikes have been a feature of planetary evolution in our solar system for billions of years.
Scientists are now studying the possible role of asteroids bringing water and even life to Earth. Where there's life, there's death, and killer asteroids can apparently generate a lot of death.
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