WASHINGTON — It was an offer President Barack Obama couldn't refuse.

"You're welcome to try this out if you like," the Oakland Park, Fla., high school student said.

With that, a president who often laments a lifestyle that denies him the pleasure of driving eagerly hopped on the blue-and-silver bicycle in his dark blue suit and pedaled away — never mind that the machinery didn't take him anywhere.

"Only because these guys really want this," Obama said, gesturing to the small group of reporters and photographers who were brought to a White House garden on Monday to watch the president go from exhibit to exhibit at his third White House science fair.

He said afterward that the science fair is "one of my favorite events during the course of the year."

As Obama pedaled, Payton Karr and Kiona Elliot, classmates at Northeast High School, explained their pedal-powered water filtration system. The collapsible, transportable emergency water-sanitation station filters E. coli and other harmful pathogens from contaminated water. During emergencies, the device can be assembled and broken down in less than an hour, and can produce enough water for 20 to 30 people during a 15-hour period.

Karr and Elliot were among some 30 student teams that were invited to the White House to show off projects that won them top honors in science, technology, engineering and math competitions around the country.

Jewel Samad / AFP - Getty Images

President Barack Obama paddles a bicycle-powered emergency water-sanitation system in the East Garden on Monday, during the White House science fair.

Jewel Samad / AFP - Getty Images

President Barack Obama checks out a low-cost mini-press that can turn biomass waste products such as banana peels into a viable wood alternative for cooking. The device was designed by students from Pinelands Eco Regional High School in New Jersey.

Larry Downing / Reuters

President Barack Obama views the winning entry in the BEST Robotics category with students from St. Vincent de Paul Middle School in Theodore, Ala., as he hosts the White House science fair in the State Dining Room at the White House. The "Vator" robot is designed to mimic a space elevator by lifting cargo up a 10-foot pole.

Rockets, robots rule
Rockets and robots were among the exhibits, too, along with a fully functioning prosthetic arm that 17-year-old Easton LaChapelle, of Mancos, Colo., made mostly with parts generated from a 3-D printer. He said it cost just a few hundred dollars to make, far less than the $80,000 replacement arm he said had inspired him.

The arm apparently functioned up until a few minutes before Obama stopped at Easton's exhibit in the State Dining Room. Easton told Obama that he'd planned for the prosthetic arm to shake the president's hand. Obama shook hands with the disembodied arm anyway, "because it was working," he said.

Three pint-sized students from Flippen Elementary School in McDonough, Ga., told Obama about the "Cool Pads" they created to help football players stay cool on the field. Evan Jackson, 10, Alec Jackson, 8, and Caleb Robinson, 8, developed the pads for the shoulders, helmet, armpits and groin with built-in temperature sensors to help keep players from overheating. Gatorade is in there, too, so players don't have to leave the field to hydrate.

Obama called their invention "pretty spiffy."

During more formal remarks after he visited a total of a dozen exhibits, Obama praised the students and their projects, which included new ways to detect cancer, create alternatives to burning wood for fuel and breeding new types of algae.

"Young people like these have to make you hopeful about the future of our country," he said.

AmeriCorps effort
Obama also announced a new effort to link AmeriCorps national service members with nonprofit groups that promote science, technology, engineering and math. Since taking office in 2009, Obama has been pushing to increase the number of students, including girls, and teachers who pursue these fields.

He also saw the rocket built by Darius Hooker, 19, of Memphis, Tenn., and his high-school classmate Wesley Carter that propelled eggs more than 800 feet into the air and then brought them down unbroken in less than a minute.

"Did the eggs come down OK?" Obama asked.

Hooker said in a telephone interview afterward that he was always interested in "anything that goes up" and that he now thinks of himself as a role model.

"We motivate a lot of people that's our age, younger than us and older than us," he said. Hooker is currently studying for a license in aircraft mechanics at Tennessee Technology Center in Memphis.

More about science at the White House:

• 5 areas of science due for a budget boost
• Obama awards top honors to scientists
• White House pitches brain-mapping project

Copyright 2013 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

NASA says it will begin work on an ambitious mission to capture a near-Earth asteroid and bring it to a stable orbit in the Earth-moon system as part of the agency's overall $17.7 billion agenda for the coming year.

The budget request for fiscal year 2014, unveiled on Wednesday, also aims to get U.S. astronauts back to flying on U.S.-based spaceships by 2017, launch the $8.8 billion James Webb Space Telescope by 2018 and send another rover to Mars by 2020. 

The proposed budget is about $50 million less than the amount sought a year ago, but about $1 billion more than the agency's current spending plan. Billions of dollars would be set aside to continue operations on the International Space Station, keep up the work on interplanetary missions, expand the nation's network of Earth-observing satellites and upgrade aerospace technologies. However, the headline-grabber in the budget is the asteroid retrieval mission, which is budgeted for $105 million in spending during the fiscal year beginning in September.

"This mission represents an unprecedented technological feat that will lead to new scientific discoveries and technological capabilities and help protect our home planet," NASA Administrator Charles Bolden said in a statement accompanying the budget request.

Planning documents suggest that the space agency would launch a probe powered by a next-generation solar electric propulsion system sometime around 2017, to rendezvous with a 7- to 10-meter-wide (25- to 33-foot-wide) asteroid around 2019. A collapsible shroud would be wrapped around the asteroid, and then the probe would pull the space rock to a stable point in high lunar orbit or at a gravitational balance point beyond the far side of the moon.

Speaking on condition of anonymity, officials familiar with the plan told NBC News that NASA was already beginning the work to identify a candidate asteroid. The 2014 budget includes $78 million for planning the mission, and $27 million to accelerate NASA's efforts to detect and characterize potentially hazardous asteroids. NASA's chief financial officer, Elizabeth Robinson, indicated that this spending would come in addition to the $20 million that the space agency currently spends annually on asteroid detection.

The plan for the mission was formally unveiled less than two months after an asteroid streaked through the atmosphere and broke up over Russia. The breakup sparked a meteor blast that shattered windows and injured more than 1,000 people.

That asteroid was thought to have been about 17 meters (55 feet) wide. The type of asteroid targeted for the future NASA mission, in contrast, would be too small to pose a threat to Earth — even if it were to break loose somehow and plunge through the atmosphere.

Astronauts to visit
Bolden said the asteroid-grabbing mission meshed with NASA's plans to head off cosmic threats as well as to prepare for deep-space human exploration. Eventually, astronauts would be sent to study the captured asteroid and bring back samples, most likely during a beyond-the-moon test mission that's already planned for 2021.

"This asteroid initiative brings together the best of NASA's science, technology and human exploration efforts to achieve the president's goal of sending humans to an asteroid by 2025," Bolden said. "We will use existing capabilities such as the Orion crew capsule and Space Launch System rocket, and develop new technologies like solar electric propulsion and laser communications — all critical components of deep-space exploration."

A senior administration official told NBC News on condition of anonymity that the added cost of the asteroid mission would be around $1 billion, spread over several years. That figure doesn't include the estimated $35 billion that is being paid out to develop the SLS/Orion system for deep-space human flights.

As Bolden noted, the asteroid mission would satisfy President Barack Obama's space exploration goal for 2025, and allow NASA to turn its attention to sending astronauts to Mars and its moons in the 2030s. Last week, Bolden signaled that other potential objectives, such as sending humans back to the moon, were not on the agenda for the foreseeable future.

Nevertheless, some lawmakers want NASA to go in a different direction: A bipartisan group of House members last week reintroduced a bill calling on the space agency to develop a plan for establishing a permanent human presence on the moon.

"Last year, the National Research Council committee charged with reviewing NASA’s strategic direction found that there was no support within NASA or from our international partners for the administration’s proposed asteroid mission," Rep. Frank Wolf, R-Va., said in a statement. "However, there is broad support for NASA to lead a return to the moon. So the U.S. can either lead that effort, or another country will step up and lead that effort in our absence — which would be very unfortunate."

No guarantees
NASA's $17.7 billion spending plan accounts for less than half a percent of Obama's $3.8 trillion request to Congress for fiscal 2014. The entire budget is likely to come under close scrutiny in the Republican-controlled House as well as the Democratic-controlled Senate, and there's no guarantee that the final version will look anything like the White House's proposal. In fact, last year's budget request ended up going nowhere. Instead, the federal government is currently operating under a budget sequestration plan that cut back on previous spending levels.

"This was a meat-ax approach that I think nobody initially intended to have take effect," White House science adviser John Holdren said Wednesday during a budget briefing.

Holdren said the total amount of money budgeted for research and development in 2014 would come to $142.8 billion, which represents a "small decline" in inflation-adjusted dollars compared with 2012 spending levels.

"Although this is not the budget that we would want if financial times were better, it reflects an extraordinary effort by this administration to preserve a key investment in research, development, innovation and STEM [science, technology, engineering and math] education that our country's future requires," Holdren said.

Update for 9:15 p.m. ET April 10: NASA's asteroid retrieval mission could complement commercial efforts to identify and exploit bigger near-Earth objects, said Chris Lewicki, president of the Planetary Resources asteroid-mining venture. He said he's already been involved in an "ongoing discussion" about how such a mission could benefit the public as well as private enterprise.

"Maybe this is a model for a COTS-like program where there are operations put in place for private industry to help develop a marketplace," Lewicki told NBC News.

But Lewicki said the mission will not be easy. "It represents something new that will require NASA and the contractors that help them do it to really stretch their capabilities," he said.

For example, Lewicki said it would be "very challenging" to identify and track deep-space objects in the size range that NASA is targeting — that is, 7 to 10 meters wide. Such objects usually can't be spotted unless they make a close approach to Earth.

"With what's been proposed in the budget, NASA is putting more money on the table to accelerate and leverage more observation activities," Lewicki said. "The question is, is that enough? And is it going to be soon enough?"

More reaction:

• Planetary Resources: Asteroid plan offers 'bold new thinking'
• Deep Space Industries calls for partnerships (via Moon and Back)
• University of Arizona experts welcome asteroid plan
• Rep. Lamar Smith, R-Texas: Plan comes 'seemingly out of the blue'
• Coalition for Space Exploration backs budget proposal

More about asteroids:

• Asteroid miners are getting a boost from NASA
• How asteroid mission could lead to Mars
• Cosmic Log archive on asteroids

Correction: I originally wrote that the full budget proposal was seeking $3.8 billion, but it's actually $3.8 trillion. Unfortunately, it's not the first time one of those wayward "illions" has slipped through the net. Thank goodness I have sharp-eyed commenters to set me straight.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

This story was originally published on Wed Apr 10, 2013 2:54 PM EDT

DigitalSpace

An Orion exploration vehicle approaches a near-Earth asteroid in this artist's conception. Such a mission would be carried out in 2021 under the White House's new plan for NASA exploration beyond Earth orbit.

NASA's accelerated vision for exploration calls for moving a near-Earth asteroid even nearer to Earth, sending out astronauts to bring back samples within a decade, and then shifting the focus to Mars, a senior Obama administration official told NBC News on Saturday.

The official said the mission would "accomplish the president's challenge of sending humans to visit an asteroid by 2025 in a more cost-effective and potentially quicker time frame than under other scenarios." The official spoke on condition of anonymity because there was no authorization to discuss the plan publicly.

The source said more than $100 million would be sought for the mission and other asteroid-related activities in its budget request for the coming fiscal year, which is due to be sent to Congress on Wednesday. That confirms comments made on Friday by Sen. Bill Nelson, D-Fla., a one-time spaceflier who is now chairman of the Senate Commerce Subcommittee on Science and Space. It also confirms a report about the mission that appeared last month in Aviation Week.

The asteroid retrieval mission is based on a scenario set out last year by a study group at the Keck Institute for Space Studies. NASA's revised scenario would launch a robotic probe toward a 500-ton, 7- to 10-meter-wide (25- to 33-foot-wide) asteroid in 2017 or so. The probe would capture the space rock in a bag in 2019, and then pull it to a stable orbit in the vicinity of the moon, using a next-generation solar electric propulsion system. That would reduce the travel time for asteroid-bound astronauts from a matter of months to just a few days.

The Keck study estimated the total mission cost at $2.6 billion — but the administration official said the price tag could be reduced to $1 billion, or roughly $100 million a year, if the mission took advantage of an already-planned test flight for NASA's heavy-lift Space Launch System rocket and Orion crew exploration vehicle. That flight would send astronauts around the moon and back in 2021.

"This mission would combine the best of NASA's asteroid identification, technology development, and human exploration efforts to capture and redirect a small asteroid to just beyond the moon to set up a human mission using existing resources and equipment, including the heavy-lift rocket and deep-space capsule that have been under development for several years," the official said in an email.

The 2014 budget would set aside $78 million for planning the asteroid retrieval mission, plus $27 million to accelerate NASA's efforts to detect and characterize potentially hazardous asteroids. The federal government currently spends $20 million annually on asteroid detection.

Meteor sparked action
The official said the plan had been under discussion for months, but coalesced after February's meteor blast over Russia. The meteor's breakup injured more than 1,000 people and sparked a worldwide sensation. It also sparked a series of congressional hearings about threats from space, during which Republicans as well as Democrats hinted that they would support more funding to counter asteroid threats.

"This plan would help us prove we're smarter than the dinosaurs," said the official, referring to the asteroid that wiped out the dinosaurs and many other species 65 million years ago. An asteroid in the 7- to 10-meter range would be about half as wide as the one that broke up over Russia. That's far too small to pose any threat to Earth, even if the space rock was coming directly at our planet. But the captured asteroid could provide valuable insights for dealing with bigger ones in the future. 

Initial preparations for the mission won't have to wait for a deal to end budget sequestration, or approval of the budget for the 2014 fiscal year. NASA would begin immediately to identify the asteroid for retrieval, and take advantage of existing efforts funded by the agency's science, technology and human exploration directorates. The most expensive element of the plan, the multibillion-dollar Orion/SLS launch system, is already being funded under the terms of an agreement with Congress.

Discussions with NASA's international and commercial partners will continue in the months and years ahead, the official said. The retrieved asteroid could conceivably become a target for other scientific missions or asteroid-mining operations. In the process, governments might have to address issues surrounding the ownership and exploitation of space resources.

"We're trying to force the question," the official said. "We're trying to push the envelope on this new frontier."

Questions raised
Some observers have already raised questions about the plan, based on the advance reports. Scott Pace, the director of George Washington University's Space Policy Institute, told The Associated Press that it was a bad idea on scientific as well as diplomatic grounds. It would be better for the United States to join forces with other countries to conduct a comprehensive survey of all potentially dangerous asteroids, Pace said.

Rick Tumlinson, chairman of an asteroid-mining venture called Deep Space Industries, said he was concerned that NASA's asteroid mission might interfere with private-sector efforts — and he called on NASA to rely on private enterprise wherever possible. The administration official assured NBC News that cooperation with commercial ventures as well as other groups such as the B612 Foundation was part of the plan.

The official noted that the mission would provide a relatively low-cost route to satisfying President Barack Obama's goal of sending astronauts to a near-Earth asteroid by 2025. The lessons learned during the mission could be applied to future missions aimed at diverting other asteroids — perhaps to head off a potential threat, or conduct further scientific study, or exploit the potentially valuable resources that asteroids contain.

After the asteroid mission, NASA would turn its attention to a farther-out destination: Mars. The Obama administration has called for astronauts to travel to the Red Planet and its moons by the mid-2030s, and that would be the next major target for space exploration. The administration official told NBC News that other concepts, such as sending astronauts back to the moon or creating a deep-space platform beyond the far side of the moon, are not on the agenda for the foreseeable future. 

More about asteroids:

• Asteroid miners get boost from NASA
• Senator says asteroid mission is in the works
• Cosmic Log archive on asteroids

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

L. Calcada / N. Risinger / ESO

An artist's conception shows the planet Alpha Centauri Bb, orbiting one of the stars in a nearby triple-star system. A commercial venture known as Uwingu says it will use proceeds from a contest to give Alpha Centauri Bb a new name to support endangered educational and public outreach efforts.

NASA's plan to suspend educational and public outreach activities due to budget sequestration has sparked protests from some of the space agency's biggest fans, and a commercial venture known as Uwingu wants to help fill the gap. Uwingu says it will direct proceeds from its contest to name the closest exoplanet toward projects that are facing budget cuts.

The venture was set up last year to offer space-themed entertainment that would raise money for education and space science. Just last week, Uwingu kicked off an effort to come up with a "people's choice" name for Alpha Centauri Bb, an Earth-sized planet that was detected last year just 4.3 light-years away.

It takes $4.99 to nominate a name, and 99 cents to cast a vote. The contest closes on April 15, and the winner will be announced the next day. Some of the proceeds will go toward paying the company's expenses, but the target is to put at least half of the money into a fund to support research and education. 

Rough patch for NASA
When the company made its public debut, the founders said the Uwingu Fund could serve as a lifeline for scientists and educators if NASA's budget ran into a rough patch. Sequestration certainly qualifies as a rough patch: The automatic spending cuts will force NASA to scale back its budget by roughly $900 million for the fiscal year.

As part of its plan to comply with sequestration, NASA officials on Friday ordered the suspension of educational and public outreach activities, also known as EPO. Planetary scientist Alan Stern, Uwingu's CEO and a former NASA associate administrator, said the suspension has put educational and public outreach programs "under severe and sudden stress."

"At Uwingu, we believe that private and commercial funding of space-based initiatives — including research and EPO — is more important now than ever," Stern said in a statement Monday. "That's the purpose of The Uwingu Fund, which is fueled from people participating in the naming contest for Alpha Centauri's planet. Today we're announcing that Uwingu is taking action to combat the severe, adverse impact of sequestration on NASA EPO by directing all Uwingu Funds proceeds raised through this contest to grants to EPO professionals and projects."

In the grand scheme of things, education and public outreach aren't the most expensive things that NASA does. The continuing resolution that governed spending for the current fiscal year set aside $137 million for the agency's education account, and sequestration would trim that figure by $7 million. NASA budgets additional funds for public outreach on a mission-by-mission basis, but the expense is still a small proportion of NASA's $17.8 billion budget.

Outcry over outreach
Friday's move nevertheless sparked an outcry from many who rank education and public outreach among NASA's strongest suits. Over the weekend, more than 4,500 people signed onto an online petition urging the White House to "repeal" the EPO spending cuts.

"This is something that hits extremely close to home, and not just because I may not have a position this summer as a result of this," Scott Lewis, media director for Astrosphere New Media Association, said in a Google+ posting. "NASA's education and public outreach is something that opens the eyes of thousands, if not millions of people, to the magnificence of science, technology, engineering and mathematics."

One of the ventures that could be affected by the budget cuts is CosmoQuest, an online educational project that sponsors virtual star parties, citizen-science projects and similar activities with NASA support. Pamela Gay, a professor at Southern Illinois University who is CosmoQuest's project director, said the effect on funding is not yet clear — but she's already preparing for cutbacks.

"I'm looking at multiple fundraisers," Gay, who is on Uwingu's board of advisers, said in a Google+ posting on Sunday. "While I'm less worried about CosmoQuest than I was yesterday, it is clear that many good people in the NASA EPO community are deeply in jeopardy. I continue to encourage you to help us seek donations so that I can recover as needed from any cuts we incur, and, as additional funding allows, work to contract people who do lose their jobs to help us build new and amazing things for CQX. I'm hoping you will help me build a safety net for our community."

Correction for 3:55 p.m. ET March 25: I referred to Scott Lewis as an astronomer at Citrus College — which prompted this email from Lewis, a.k.a. "The Bald Astronomer": "I'm not an astronomer at Citrus College, but a student there. I am, however, media director for Astrosphere New Media Association, on the education/public outreach team for CosmoQuest, owner of KnowTheCosmos.com, and an all-around attractive man. haha."

More about sequestration's effects: 

• Sequester keeps NASA officials from conference
• FAA to close 149 air traffic control towers
• Budget battles: What you need to know

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

NASA via Twitter

NASA says the tweets will continue despite a "pause" in educational and public outreach initiatives.

NASA is putting the brakes on its educational and public outreach efforts, due to the continuing standoff over the federal budget and the resulting sequestration of the agency's funds.

The cutbacks in NASA's activities, including social-media initiatives, were outlined on Friday in a pair of memos from NASA Headquarters in Washington. The independent SpaceRef website published both memos, including one that ordered a suspension and another that provided additional instructions for NASA's Communication Coordinating Council.

Automatic spending cuts are taking effect, at NASA and many other federal agencies, as the result of the failure by the White House and Congress to agree on a budget deal. Last month, NASA Administrator Charles Bolden told lawmakers that sequestration would reduce NASA's overall budget from the $17.8 billion that Congress approved last year to $16.9 billion.

The space agency already has cut back on travel and training expenses. As a result, some of the space agency's scientists and executives had to pass up this week's Lunar and Planetary Science Conference in Texas. The new directives extend the cutbacks to online, multimedia and social-media initiatives as well as publications.

Operational websites and social-media accounts were excluded from the suspension, however — which means existing Twitter accounts, including @NASA and @MarsCuriosity, can stay in business. NASA has rapidly expanded its online presence in the past couple of years, winning recognition from the Emmys, the Shorty Awards and the Webby Awards. Just this month, the Mars Curiosity mission's social-media team won the South by Southwest Interactive Award for best social-media campaign. 

Waivers were also granted for mission announcements, media events and products, breaking-news activities and responses to media inquiries. In an emailed response to NBC News' inquiry, NASA spokesman Bob Jacobs said additional guidance would be issued next week, addressing areas that would be exempt from the suspension.

"It's important to point out that it's a suspension, not a cancellation," Jacobs wrote. "The agency's budget for the fiscal year is more that $1 billion below the original request. We are taking prudent steps to ensure the resources expended on outreach activities are done so wisely.

"Mission activities and much of the existing news and information dissemination is not likely to be impacted, including our successful social media efforts," he said. "However, it is important in this constrained fiscal environment to pause and assess how the money is being spent on a wide variety of outreach activities, many of which are funded by independent projects and programs. We are not canceling anything yet. We are being financially responsible by pausing long enough to review activities before they go forward."

Update for 9 p.m. ET March 23: Folks have started a petition on the White House's "We the People" website, calling for a repeal of the sequestration cuts for education and public outreach. Although the sentiment is admirable, NASA's hands (and the White House's hands) may be tied by the rules that govern sequestration. It's important to note that all of the space agency's activities have to be cut back by the same percentage. It's just that in the case of education and public outreach, the memos that address the process for starting the cuts have now been made public. 

That being said, signing a White House petition is a great way to make your opinion known, and so is writing or calling your representatives in Congress.

More about sequestration's effects:

• FAA to close 149 air traffic control towers
• How science funding will be affected
• Budget battles: What you need to know

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

This story was originally published on Fri Mar 22, 2013 10:00 PM EDT

Congress got the word from NASA on Tuesday about its options for dealing with the threats posed by asteroids and comets: Lawmakers can either provide adequate funding for detecting and characterizing near-Earth objects, and diverting them if necessary — or they can pray.

Threats from space are generally the stuff of science-fiction movies such as "Armageddon" and "Deep Impact," but members of the House Science Committee took a hard look at the realities during Tuesday's hearing, which came in response to the Feb. 15 meteor explosion over Russia as well as a close encounter that same day with a much bigger asteroid known as 2012 DA14.

The lawmakers didn't always like what they heard. The committee's chairman, Rep. Lamar Smith, R-Texas, told the panelists more than once that the progress report they delivered was "not reassuring." But representatives from both parties were receptive to the idea of putting more resources into the effort to counter cosmic threats.

White House science adviser John Holdren noted that the funding devoted annually to cataloging potentially threatening asteroids has risen from $5 million to more than $20 million over the past couple of years. But even at that level, NASA Administrator Charles Bolden estimated that it would take until 2030 to catalog 90 percent of the near-Earth objects between 140 meters and 1 kilometer in width, as mandated by Congress.  

"Maybe we can help you out with the budget. Don't know," Smith replied. He said "we need to find ways to prioritize NASA's projects."

Holdren said the single most useful project would be to put an infrared-sensing telescope in a Venus-like orbit, like the Sentinel Space Telescope being developed by the nonprofit B612 Foundation. The telescope could look for asteroids that currently can't be spotted from the ground because they spend much of their time within Earth's orbit, where they're lost in the sun's glare. The 55-foot-wide (17-meter-wide) rock that blew up without warning over Chelyabinsk in Russia last month was just such an asteroid.

"It came from a direction where our [existing] telescopes could not look," Holdren said. "We cannot look in the sun." 

Don Davis

Artwork by Don Davis shows a meteor streaking across the skies over the Russian city of Chelyabinsk. More of Davis' work is available at his website, DonaldEDavis.com.

Holdren estimated the cost of an asteroid-hunting space telescope at $500 million to $750 million, and said it could reduce the congressionally mandated survey time to six to eight years. Following through on the Obama administration's plan to send astronauts to a near-Earth asteroid by 2025 would cost about $2 billion a year, Holdren said.

The automatic spending cuts known as sequestration will affect NASA's asteroid-hunting effort as well as the plans for human exploration, Bolden warned.

"The president has a plan. But that plan is incremental," Bolden said, referring to the Obama administration's budget proposal. "And if we want to save the planet, because I think that’s what we’re talking about, then we have to get together ... and decide how we’re going to execute that plan."

The idea of enlisting other countries as well as amateur astronomers to "crowdsource" the hunt for threatening asteroids struck a responsive chord with lawmakers. But Rep. Dana Rohrabacher, R-Calif., reminded Bolden that China couldn't be on the list of partners due to a congressional ban.

Congressional teach-in
The hearing served as a teach-in for some of the panel members. At one point, Rep. Randy Weber, R-Texas, asked whether the $8.8 billion James Webb Space Telescope could be retrofitted to look for asteroids. "No, sir," Bolden replied. At another point, Gen. William Shelton, head of the Air Force Space Command, had to explain to lawmakers that the space-based surveillance system used for monitoring missile launches on Earth could not watch out for rocks coming in from deep space.

Holdren and Bolden provided a status report on the asteroid search, reporting that about 95 percent of the near-Earth objects larger than a kilometer are being tracked. However, only about 10 percent of the 13,000 to 20,000 asteroids bigger than 140 meters have been detected. If an asteroid of that size were to strike land, it "could devastate the better part of a continent," Holdren said.

Looking on the bright side, Holdren added that such asteroids are thought to hit Earth only every 20,000 years or so.

Bolden said less than 1 percent of the space rocks in the 30- to 100-meter range have been found. Such asteroids may not be continent-killers, but they are bigger and more potentially destructive than last month's Chelyabinsk meteor.

Lawmakers repeatedly asked how much advance warning would be required to deflect a threatening asteroid, and were repeatedly told that it would take years. Shelton said that if time was limited, "probably nuclear energy is what we're talking about." But even a nuclear-armed mission to blast an asteroid, Bruce Willis-style, would require lots of lead time. Rep. Bill Posey, R-Fla., asked Bolden about the strategy for dealing with an Earth-threatening asteroid that was discovered with three weeks' warning.

"If it's coming in three weeks ... pray," Bolden said. "The reason I can't do anything in the next three weeks is because for decades we have put it off."

More about threats from space:

• 'Marsageddon' comet adds to concerns
• The global plan to deal with asteroids
• Cosmic Log archive on asteroids

Ali Weinberg is an associate producer with NBC News in Washington.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Bill Ingalls / NASA

A commemorative wreath adorns a monument to the crew of the shuttle Columbia at Arlington National Cemetery in Virginia on Friday, the 10th anniversary of the shuttle's destruction and the astronauts' deaths.

President Barack Obama and NASA's leaders paid a 10th-anniversary tribute to the space shuttle Columbia's fallen astronauts on Friday — and pledged that the lessons learned would be applied to future space odysseys, including eventual trips to Mars.

"As we undertake the next generation of discovery, today we pause to remember those who paid the ultimate sacrifice on the journey of exploration," Obama said in a statement released by NASA. "Right now we are working to fulfill their highest aspirations by pursuing a path in space never seen before, one that will eventually put Americans on Mars."

The shuttle Columbia's catastrophic breakup on Feb. 1, 2003, killed seven astronauts, forced a two-year grounding of the three remaining space shuttles and led to stepped-up safety measures at the space agency. The disaster also led Obama's predecessor, President George W. Bush, to plan for the retirement of the shuttle fleet once construction of the International Space Station was complete. The last shuttle mission flew eight years later, in 2011.

Bush's space vision called for a new generation of vehicles to be built for trips back to the moon by 2020 — but Obama shifted the focus of exploration to a near-Earth asteroid in the mid-2020s, with trips to Mars and its moons starting in the mid-2030s.

'We will never forget'
In his own 10th-anniversary statement, NASA Administrator Charles Bolden said the sacrifices made by the crew of Columbia's last mission will inspire future explorers.

"We will never forget these astronauts, nor all those who have lost their lives carrying out our missions of exploration — the STS-51L Challenger crew; the Apollo 1 crew; Mike Adams, the first in-flight fatality of the space program as he piloted the X-15 No. 3 on a research flight," Bolden said in an agency statement. "These explorers, and their families, have our deepest respect. We work every day to honor and build on their legacy and create the best space program in the world — to infuse it with the life and vitality that they worked so hard to achieve."

Bill Ingalls / NASA

NASA Administrator Charles Bolden looks on as Apollo 11 moonwalker Buzz Aldrin gives a salute during a wreath-laying ceremony at Arlington National Cemetery on Friday. The ceremony paid tribute to astronauts who died in the Apollo 1 fire of 1967 as well as the 1986 Challenger explosion and the 2003 Columbia tragedy.

Slideshow:

Retrace the final, tragic flight of the space shuttle Columbia, from its launch to its catastrophic end on Feb. 1, 2003.

Launch slideshow

On Friday morning, Bolden laid a wreath in honor of the agency's fallen astronauts at Arlington National Cemetery in Virginia, where monuments to the Columbia and Challenger crews have been erected. Earlier in the week, he attended a spaceflight conference held in Israel to honor Ilan Ramon, that country's first astronaut, who died in the Columbia tragedy. The other victims included Columbia commander Rick Husband, William McCool, Michael Anderson, David Brown, Kalpana Chawla and Laurel Clark.

Memorial ceremonies also were conducted in Texas, where the Columbia wreckage fell to earth, and at Kennedy Space Center's visitor complex in Florida. The focal point of the Florida ceremony was the Space Mirror Memorial, which bears the names of NASA fliers who died in the line of duty.

Roots of the tragedy
At that ceremony, Bill Gerstenmaier, NASA's associate administrator for human exploration and operations, acknowledged that the roots of the Columbia disaster went "all the way back to the first shuttle launch in 1981." Even then, NASA knew that ice and pieces of foam insulation could fly off the shuttle's external fuel tank and strike the orbiter — but the fact that no severe damage was done "reinforced the idea that all was well," Gerstenmaier said.

That view changed dramatically when Columbia was felled. Investigators determined that the leading edge of Columbia's left wing was fatally damaged by a piece of flying foam during launch, setting the stage for the breakup 16 days later during atmospheric re-entry. NASA was reminded that "even small problems can surface as major failures," Gerstenmaier said.

"Ten years ago, it would have been easy to pull back from the frontier of space, and say it was too risky to pursue," he said. "Instead, we dedicated ourselves to improving how we pushed the boundaries of space exploration, and we vowed to continue with our eyes open. We cannot be afraid of risk, and we cannot be ignorant of it, either. Our lasting tribute to those we have lost is to carry on with the cause that they believed was worth the ultimate sacrifice."

Other speakers at the Florida ceremony included Evelyn Husband-Thompson, the widow of Columbia's commander, who has since remarried. She recalled how she and other family members anticipated the return of their loved ones on that fateful Saturday morning 10 years ago, only to be jolted into a nightmare of "fear, uncertainty and horror."

NASA

Evelyn Husband-Thompson, the widow of Columbia commander Rick Husband, speaks at a memorial ceremony conducted Friday at the Space Mirror Memorial at Kennedy Space Center's visitor complex.

"The grief journey has been difficult, complicated and surprising," she said. Over the past decade, she has drawn comfort from her friends, her family and her faith. She noted that the Columbia crew's legacy includes educational initiatives, scholarships, museum exhibits, and even the name of the airport near her home in Texas: Rick Husband Amarillo International Airport.

"Just as a forest fire reduces beautiful foliage to ashes, those ashes ultimately become nourishment for new, healthy growth," Husband-Thompson said. "There are indeed small, green shoots of hope that are springing up in our lives."

More about Columbia:

• 10 years later, Columbia's loss still stings
• Shuttle tragedies serve as warnings to NASA
• 10 myths surrounding the Columbia tragedy
• NASA celebrates its fallen astronauts
• Film finds uplifting story amid Columbia's loss

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

NASM

This model of the fictional Starship Enterprise was used in the weekly hourlong "Star Trek" TV series that aired September 1966 to June 1969. It is now on display in the Smithsonian's National Air and Space Museum.

If the Death Star went up against the Starship Enterprise, who would win? When it comes to White House petition drives, it's the Death Star.

The petition calling on the federal government to build a fully operational "Star Wars" battle station attracted more than 34,000 signatures, forcing the White House to issue a hilarious response. But a similar petition supporting a real-life version of Captain James T. Kirk's favorite ride fell far short of the 25,000-signature requirement when the one-month deadline passed on Monday.

At last count, the Enterprise petition had 7,200 signatures, according to its creator, a Trek fan known publicly as BTE-Dan. "I’m disappointed that it didn't reach 25,000, because I would have genuinely liked to have seen the Obama administration respond to it," Dan told NBC News in an email. 

Dan is the webmaster behind the "Build the Enterprise" website — and he says he's serious about wanting NASA to do a feasibility study for an Enterprise-like spaceship.

"I really do think that building an interplanetary spaceship that follows the form of the USS Enterprise would be uniquely inspirational to Americans, and people around the world, too," he wrote. "Once its construction started in space, people would be fascinated by it, and it would constantly be in the news. And it might well inspire a new generation of Americans to study the STEM subjects [science, technology, engineering, math]."

Dan likes the basic idea behind the Obama administration's "We the People" program, which provides an opportunity for petitioners to get a response from the White House if enough people sign on.

"Unfortunately, having a short 30-day window to gather signatures makes the petition system geared to getting high signature counts mainly for the most emotionally charged current events of the moment, like pro-gun control, or anti-gun control, or the desire of some to deport Piers Morgan," he said. "People are motivated by humor, too, like in the Piers Morgan case and for the Death Star petition, and there is nothing wrong with having some fun with the petitions. But I’d like to see the system changed so that more substantive petitions get considered."

Maybe the problem was that BTE-Dan's proposal was too substantive, especially for a concept that sounds like classic science fiction. The same issue might be working against another space-themed petition, calling on the federal government to build a nuclear thermal rocket. (NASA actually pursued a nuclear-rocket development program in the 1960s, and may do so again.) That campaign has attracted fewer than 2,300 of the required 25,000 signatures with 10 days to go before the deadline.

One thing's for sure: It'll be even harder for slightly wacky petitions like the Death Star plea, or an earlier effort to crack the alien conspiracy, to make their way into the spotlight in the future. That's because the White House raised the signature requirement from 25,000 to 100,000 last week. BTE-Dan's effort just might stand as the most ambitious effort to build a real-life Starship Enterprise until the year 2063 — when eccentric genius Zefram Cochrane achieves the first warp drive flight and brings the Vulcans in for first contact.

More about starships and petition drives:

• Scientists say warp drive is more feasible than they thought
• Empire strikes back with response to Death Star petition
• Video: White House petition calls for VP reality TV show

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.