China considering space-based solar power station

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Chinese scientists say a solar power station in a geosynchronous orbit could supply a constant stream of electricity.

NASA's conceptual drawing of a space-based solar power station. Credit: NASA

Chinese scientists are considering how they can build and put into orbit a massive space station that would supply a constant stream of solar energy to Earth.

The project, which is still in the conceptual stage, would involve a satellite that weighs more than 10,000 lbs., dwarfing anything previously placed into orbit, including the International Space Station, according to the China-based Xinhuanet, part of the Xinhua News Agency.

While space-based solar power is not a new idea, some Chinese scientists believe a collector could be launched as soon as 2020, although others place the launch date further out, as far away 2050.

"China will build a space station in around 2020, which will open an opportunity to develop space solar power technology," Li Ming, vice president of the China Academy of Space Technology, was quoted as saying to the Xinhuan news agency.

Members of the both the Chinese Academy of Sciences (CAS) and the Chinese Academy of Engineering (CAE) wrote a report five years ago that suggested China should begin with an experimental space-based solar power station by 2030, and build a commercially viable space power station by 2050.

Wang Xiji, of the CAS and a member of the International Academy of Astronautics, said building a solar space station is feasible, although it would be an unprecedented and monumental task.

Xiji said a solar space station in a geosynchronous orbit could circumvent the problem with intermittent energy production on Earth, which must contend with nighttime and weather interruptions.

Duan Baoyan, a member of the CAE, said space-based solar panels could generate 10 times as much electricity as ground-based panels.

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China considering space-based solar power station

NASA Solicitation: Hubble Science Operations at Space Telescope Science Institute

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SCIENCE OPERATIONS OF THE HUBBLE SPACE TELESCOPE AND OPERATION OF THE MIKULSKI ARCHIVE FOR SPACE TELESCOPES AT THE SPACE TELESCOPE SCIENCE INSTITUTE Synopsis - Mar 27, 2015 General Information Solicitation Number: NNG15543474 Posted Date: Mar 27, 2015 FedBizOpps Posted Date: Mar 27, 2015 Recovery and Reinvestment Act Action: No Original Response Date: Apr 10, 2015 Current Response Date: Apr 13, 2015 Classification Code: A -- Research and Development NAICS Code: 541712 Contracting Office Address NASA/Goddard Space Flight Center, Code 210.S, Greenbelt, MD 20771 Description NASA/GSFC has a requirement for the continuation of Contract NAS5-26555 with the Association of Universities for Research in Astronomy (AURA) for continued operation of the Space Telescope Science Institute (STScI) which provides full science management of the Hubble Space Telescope (HST) and supports the HST science and flight operations facility. The requirement is for the contractor to continue to provide the products and services required to execute the science program, maintain and calibrate the onboard instruments, maintain the ground systems, archive and distribute the science data, perform follow-on mission studies, manage the HST grants program, and conduct astronomical research during the remaining years of HST science mission as well as operate and maintain the Mikulski Archive for Space Telescopes (MAST). The period of performance for this effort is May 1, 2016 through April 30, 2021. NASA/GSFC intends to extend Contract NAS5-26555 with AURA under the statutory authority of 10 U.S.C. 2304(c)(1), only one responsible source. AURA is the only known source that possesses the required experience and expertise in all areas, including, but not limited to astronomy, HST operations, optics, detectors, systems engineering, public affairs, grants administration, and foreign agreements to successfully meet the specific challenging mission requirements. HST is a highly complex and internationally acclaimed spacecraft that provides astronomical observing capabilities that are unique in the world. AURA is the only contractor that possesses a complete knowledge of HST's mission requirements in the critical area of planning and schedulingknowledge that is indispensable for maximizing the science return from the observatory. AURA's expertise in science operations is required to ensure the safety of the instruments and to process and calibrate the data so that it can be easily and effectively distributed to the astronomical community. AURA has expertly and continuously refined the science operations techniques of the mission during the past 25 years to incorporate changes and has worked with the astronomical community to develop, peer-review, communicate, and coordinate these changes with the telescope's users. AURA has made extensive, complex modifications to the planning, scheduling, and command-load-generation systems to support mission-critical life-extension activities. AURA is the only known source that possesses the end-to-end life cycle knowledge and skill set to safely and effectively operate the HST instrument suite. AURA is also the only identified source with deep, growing synergies between the HST and James Webb Space Telescope (JWST) missions that demonstrably reduce risk, increase productivity, and minimize costs for both programs. The Government does not intend to acquire a commercial item using FAR Part 12. Interested organizations may submit their capabilities and qualifications to perform the effort in writing via email to Michele.R.Connerton@nasa.gov no later than 2:00 p.m. local time on April 13, 2015. Such capabilities/qualifications will be evaluated solely for the purpose of determining whether or not to conduct this procurement on a competitive basis. A determination by the Government not to compete this proposed effort on a full and open competition basis, based upon responses to this notice, is solely within the discretion of the government. Oral communications ARE NOT acceptable in response to this notice. NASA Clause 1852.215-84, Ombudsman, is applicable. The Center Ombudsman for this acquisition can be found at http://prod.nais.nasa.gov/pub/pub_library/Omb.html . Point of Contact Name: Michele R Connerton Title: Contract Specialist Phone: 301-286-6640 Fax: 301-286-1773 Email: michele.r.connerton@nasa.gov

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NASA Solicitation: Hubble Science Operations at Space Telescope Science Institute

SpaceShipOne 'Lands' on Smithsonian Floor as Museum Renovates Hall

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SpaceShipOne, the world's first privately-built piloted spacecraft, has touched down after a decade in 'Flight.'

The historic space plane, which flew three suborbital flights in 2004 and then was donated to the Smithsonian the year later, was lowered to the ground on Friday(March 27) after spending ten years suspended in the Milestones of Flight hall at the National Air and Space Museum in Washington, D.C.

"It's hard to believe it's been here 10 years already," said Valerie Neal, chair of the museum's space history division and curator responsible for SpaceShipOne, in an interview with collectSPACE.com. [Watch SpaceShipOne's Historic X Prize Flight (Video)]

SpaceShipOne's 'landing' was part of ongoing renovations to the hall, the first major redesign to Milestonessince the museum opened in 1976. The museum plans to have the new "Boeing Milestones of Flight Gallery" ready in time for its 40th anniversary in 2016.

Workers carefully placed SpaceShipOne on the floor next to its formerly-suspended companion, Charles Lindbergh'socean-crossing airplane, the Spirit of St. Louis, which had been similarly lowered from Milestones' ceiling in January. There the two will remain for the next couple of months as they're inspected and undergo preservation work, awaiting their re-suspension.

Neal did not anticipate SpaceShipOne requiring any repair, but she said she might take the opportunity to get a better look at its aft section.

"There are a lot of signatures on the exhaust nozzle and I may go take a closer look at those," she shared. "I think they had a little signing party before they turned it over to us, or perhaps when it first landed."

Created by prolific aircraft designer Burt Rutan and funded by Microsoft cofounder Paul Allen, SpaceShipOne was air launched from the carrier aircraft White Knight, also built by Rutan's Scaled Composites. Dropped from underneath the aircraft, SpaceShipOne was rocketed to space using a hybrid motor and then employed a unique "feathered" tail system to return to Earth as a glider.

The craft flew to space three times: twice with pilot Mike Melvill at the controls on June 21 and Sept. 29, 2004, and once with Brian Binnie on Oct. 4 of the same year. Its two latter flights claimed the $10 million Ansari X Prize offered for the first private vehicle to twice exceed 62 miles (100 kilometers) altitude in less than two weeks.

The Smithsonian, which awarded Rutan and his Scaled team with the National Air and Space Museum trophy for their achievement, chose SpaceShipOne for Milestones of Flight because of what it represented for the near future.

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Pineapple Heads CEO Megan Sanders on capital raising mission

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JOHN ANTHONY

Last updatedTue Mar 31 05:15:59 UTC 2015

Lawrence Smith

Pineapple Heads chief executive and founder Megan Sanders gives her son Jimmy D'Audney, 4, a good head scrub.

A solo mother is hoping to raise at least $189,000 through crowdfunding to grow her childrens' hair and bath products business, Pineapple Heads.

Megan Sanders, 43, a former advertising executive launched Pineapple Heads in 2011 after identifying an opportunity in the market for all natural, New Zealand-made children's hair and bath products.

"I was looking for something natural that was fun," Sanders said.

Lawrence Smith

A crowd funding campaign is underway to raise up to $389,000 for Pineapple Heads.

The Pineapple Heads range is for children aged 10 months to 10 years and includes a pineapple shampoo, lemon balm conditioner, lime hair gel and red apple and nectarine bubble bath liquid, each with its own character.

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Pineapple Heads CEO Megan Sanders on capital raising mission

Wynn Suebhongsang / 1st Place / VIRginia International Raceway / Deft Motion / NASA TT / March 2015 – Video

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Wynn Suebhongsang / 1st Place / VIRginia International Raceway / Deft Motion / NASA TT / March 2015
This was my first time at VIR. I am still leaving a couple of seconds out there but I am happy with my time. Gapped the TTB feild by over 3 seconds and could have podiumed in TT3. I will be...

By: wynn suebhongsang

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Wynn Suebhongsang / 1st Place / VIRginia International Raceway / Deft Motion / NASA TT / March 2015 - Video

NASA Assures Skeptical Congress That James Webb Telescope Is on Track

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The program will not repeat past mistakes, officials vow, and will launch as planned in 2018

A telescope project that has become notorious for its ballooning cost and repeated delays has lately been operating on schedule and within budget, NASA officials told Congress last week. One of the most ambitious and powerful observatories ever built, the $8.8-billion James Webb Space Telescope (JWST) is on track to launch in 2018, said John Grunsfeld, associate administrator of NASAs Science Mission Directorate. Northrop Grumman, the prime contractor hired to build the telescope, has lately been troubleshooting a problem with the cryocooler meant to stop heat from interfering with the telescopes sensitive infrared camera, which requires frigid temperatures to see such long wavelengths. The issue raised fears in Congress that the observatory would be delayed, or worsethat it might not work, just as its predecessor, the Hubble Space Telescope, failed to operate properly at first and had to be repaired by shuttle astronauts. Unlike Hubble, however, James Webb is not designed to be serviced in space. Whatever we put up has to work the first time, Oklahoma Republican Rep. Frank Lucas said at the U.S. House of Representatives Subcommittee on Space hearing. Those of us who were paying attention 25 years ago remember the initial trauma after the launch of Hubble. Lets talk for a moment about this cryocooler business. Telescope managers assured the representatives that the cryocooler problems were under control, and that the difficulties were reasonable given that the instrument must operate at much colder temperatures than previous coolers. This is a very challenging jobin fact more challenging than we anticipated, said Jeffrey Grant, sector vice president and general manager of space systems at Northrop Grumman. Weve made great progress. The JWST is designed to look farther into the universe than ever before, to spot some of the first stars and galaxies that formed around 13 billion years ago. Back before 2000 NASA officials estimated the telescopes price tag at around $1 billion, and expected it to be able to launch between 2007 and 2011. After repeatedly falling behind schedule and over budget, Congress threatened to cancel the program altogether. But a replan and management overhaul in 2011 saved the scope and put in place the new 2018 deadline. With just three years remaining before JWSTs planned launch onboard a European Space Agency Ariane 5 rocket from Kourou, French Guiana, NASA has 10 months of margin left in the schedule to accommodate delays without pushing back the launch date. That is more time than most NASA projects have at this stage, Grunsfeld said. Still, there is not much room for more problems like the cryocooler. While 10 months is still a lot of time and well within the program, there are still reasons to be concerned, said Cristina Chaplain of the U.S. Government Accountability Office (GAO), which has been overseeing progress on the JWST. Most space projects encounter problems they did not expect to encounter in this phase. Rep. Donna Edwards (DMd.) wondered if 10 months was enough: The question is how much the cryocooler is going to eat into that reserve. Chaplain also complained that Northrop Grumman refused to allow GAO officers to interview its employees anonymously during the oversight analysis. This is a key best practice and a fundamental part of our methodology, she said. Anytime we are denied access to people or documents we are concerned because it could be a sign that an entity is concerned about what we will find. Grumman insisted the interviews would have been unfair to its workers. It wasnt just anonymous but isolating our junior employees, Grant said. I was unwilling to send these employees in by themselves. Ultimately NASA managers held firm that the JWST will not be delayed again. The James Webb Space Telescope has been making exceptional progress, Grunsfeld said. I have confidence that we will be ready to launch this ambitious observatory in 2018. After the telescope launches, the biggest slice of the NASA budgetthe JWST development fundingwill be freed up for future years. Partisans for different projects are already eyeing that money, and lawmakers questioned how NASA plans to divvy up the spoils. With overall budgets remaining flat, how the other $600 million a year will be reallocated after launch is one of the most important decisions facing NASA and the Congress, said Space Subcommittee Chair Rep. Steven Palazzo (RMiss.). He advocated distributing it among the programs, particularly in the planetary sciences, that were squeezed to route money to the JWST. For the sake of future projects as well as the beleaguered scope, both lawmakers and the aerospace teams are crossing their fingers for 2018.

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NASA Enters Key Partnerships for Deep-Space Missions

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Washington: NASA has selected 12 Next Space Technologies for Exploration Partnerships (NextSTEP) to develop the exploration capabilities necessary to enable commercial endeavours in human exploration to deep-space destinations such as Mars.

Through these public-private partnerships, selected companies will prepare concept studies and technology development projects in the areas of advanced propulsion, habitation and small satellites.

This work ultimately will inform the strategy to move human presence further into the solar system.

Results from these studies and hardware developments will also help determine the role for international partner involvement by fully exploring domestic capabilities, and for Orion and Space Launch Systems missions in cis-lunar space - the space around the moon.

This work will advance system understanding and define a need for further testing of habitation systems and components on the International Space Station (ISS), NASA said in a statement.

Selected advanced electric projects will develop propulsion technology systems in the 50-300 kilowatt range to meet the needs of a variety of deep-space mission concepts.

State-of-the-art electric propulsion technology currently employed by NASA generates less than five kilowatts, and systems being developed for the Asteroid Redirect Mission (ARM) are in the 40-kilowatt range.

Three NextSTEP advanced propulsion projects - $400,000 to $3.5 million per year - will have no more than a three-year performance period.

The seven NextSTEP habitat projects will have initial performance periods of up to 12 months, at a value of $400,000 to $1 million for the study and development efforts, and the potential for follow-on phases to be defined during the initial phase.

The last two NextSTEP CubeSat projects will have fixed-price contracts.

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You Can Watch NASA Test Its Mars Flying Saucer Tomorrow

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NASA You Can Watch NASA Test Its Mars Flying Saucer Tomorrow

The Low-Density Supersonic Decelerator will take its first big step on the road to Mars tomorrow. The spacecraft will undergo a "spin table test" at the Pacific Missile Range Facility in Hawaii. The event will stream from 12 to 1 p.m. EST on NASA JPL's live stream.The 15-foot-diameter craft is shaped like a flying saucer, and inflates to its size through a series of balloons that increase the surface area of the craft. It uses drag to decelerate from Mach 3 to Mach 2, preparing its payload for a softer landing on the Martian surface. This table test is a demonstration of how the craft will spin as it decelerates NASA's cargo during the descent.Because Mars has a much thinner atmosphere than Earth, simple solutions like a parachute are typically not enough on their own to slow down a spacecraft to a safe speed. That's why NASA has to use creative solutions like the sky crane that lowered Curiosity to the Martian surface.The LDSD is also meant to save on rocket fuel during landings, which would allow NASA to use the rockets for "final maneuvers and landing procedures." In addition, LDSD potentially could haul heavier cargo and land it at higher altitudes, enabling NASA to explore more varied terrain, like mountains and plateaus. The system has been through one successful flight test in June 2014 to determine its flight readiness, though that was not a full-scale launch.Eventually, NASA will conduct full flight tests with its flying saucer in Earth's atmosphere. If it works, then perhaps one day this will be the system that allows manned missions to safely descend to the martian surface.Source: NASA

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Twin Fools NASA at Brother's Launch on 1-Year Flight

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Astronaut Scott Kelly's identical twin pulled a fast one on NASA right before his brother blasted off on a one-year space station mission.

NASA Administrator Charles Bolden told Kelly on Monday that he almost had a heart attack when his brother showed up launch morning without his usual mustache late last week.

"He fooled all of us," Bolden said. Mark Kelly's mustache was "the only way I can tell you two apart."

Mark, a former space shuttle commander, was still clean shaven as of Monday afternoon, as he chatted with Bolden about the unprecedented medical experiments planned on the twins over the coming year. Doctors want to see how the space twin's body compares with his genetic double on the ground.

Scott Kelly arrived at the International Space Station on Friday night following a launch from Kazakhstan. He will remain on board until next March, as will Russian cosmonaut Mikhail Kornienko.

It will be NASA's longest spaceflight ever.

"It's like coming to my old home," said Kelly, who spent five months at the space station in 2010-2011.

The White House, meanwhile, sent congratulations Monday.

President Barack Obama's science adviser, John Holdren, wished Kelly, Kornienko and the rest of the crew the best of luck and noted that the yearlong mission is an important milestone on the path to sending humans to Mars in the mid-2030s.

"You guys are all heroes up there, and we're depending on you," Holdren said in a phone hookup.

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Twin Fools NASA at Brother's Launch on 1-Year Flight

NASA Assures Skeptical Congress That the James Webb Telescope Is on Track

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The program will not repeat past mistakes, officials vow, and will launch as planned in 2018

A telescope project that has become notorious for its ballooning cost and repeated delays has lately been operating on schedule and within budget, NASA officials told Congress last week. One of the most ambitious and powerful observatories ever built, the $8.8-billion James Webb Space Telescope (JWST) is on track to launch in 2018, said John Grunsfeld, associate administrator of NASAs Science Mission Directorate. Northrop Grumman, the prime contractor hired to build the telescope, has lately been troubleshooting a problem with the cryocooler meant to stop heat from interfering with the telescopes sensitive infrared camera, which requires frigid temperatures to see such long wavelengths. The issue raised fears in Congress that the observatory would be delayed, or worsethat it might not work, just as its predecessor, the Hubble Space Telescope, failed to operate properly at first and had to be repaired by shuttle astronauts. Unlike Hubble, however, James Webb is not designed to be serviced in space. Whatever we put up has to work the first time, Oklahoma Republican Rep. Frank Lucas said at the U.S. House of Representatives Subcommittee on Space hearing. Those of us who were paying attention 25 years ago remember the initial trauma after the launch of Hubble. Lets talk for a moment about this cryocooler business. Telescope managers assured the representatives that the cryocooler problems were under control, and that the difficulties were reasonable given that the instrument must operate at much colder temperatures than previous coolers. This is a very challenging jobin fact more challenging than we anticipated, said Jeffrey Grant, sector vice president and general manager of space systems at Northrop Grumman. Weve made great progress. The JWST is designed to look farther into the universe than ever before, to spot some of the first stars and galaxies that formed around 13 billion years ago. Back before 2000 NASA officials estimated the telescopes price tag at around $1 billion, and expected it to be able to launch between 2007 and 2011. After repeatedly falling behind schedule and over budget, Congress threatened to cancel the program altogether. But a replan and management overhaul in 2011 saved the scope and put in place the new 2018 deadline. With just three years remaining before JWSTs planned launch onboard a European Space Agency Ariane 5 rocket from Kourou, French Guiana, NASA has 10 months of margin left in the schedule to accommodate delays without pushing back the launch date. That is more time than most NASA projects have at this stage, Grunsfeld said. Still, there is not much room for more problems like the cryocooler. While 10 months is still a lot of time and well within the program, there are still reasons to be concerned, said Cristina Chaplain of the U.S. Government Accountability Office (GAO), which has been overseeing progress on the JWST. Most space projects encounter problems they did not expect to encounter in this phase. Rep. Donna Edwards (DMd.) wondered if 10 months was enough: The question is how much the cryocooler is going to eat into that reserve. Chaplain also complained that Northrop Grumman refused to allow GAO officers to interview its employees anonymously during the oversight analysis. This is a key best practice and a fundamental part of our methodology, she said. Anytime we are denied access to people or documents we are concerned because it could be a sign that an entity is concerned about what we will find. Grumman insisted the interviews would have been unfair to its workers. It wasnt just anonymous but isolating our junior employees, Grant said. I was unwilling to send these employees in by themselves. Ultimately NASA managers held firm that the JWST will not be delayed again. The James Webb Space Telescope has been making exceptional progress, Grunsfeld said. I have confidence that we will be ready to launch this ambitious observatory in 2018. After the telescope launches, the biggest slice of the NASA budgetthe JWST development fundingwill be freed up for future years. Partisans for different projects are already eyeing that money, and lawmakers questioned how NASA plans to divvy up the spoils. With overall budgets remaining flat, how the other $600 million a year will be reallocated after launch is one of the most important decisions facing NASA and the Congress, said Space Subcommittee Chair Rep. Steven Palazzo (RMiss.). He advocated distributing it among the programs, particularly in the planetary sciences, that were squeezed to route money to the JWST. For the sake of future projects as well as the beleaguered scope, both lawmakers and the aerospace teams are crossing their fingers for 2018.

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NASA Assures Skeptical Congress That the James Webb Telescope Is on Track

NASA Details 2020s Asteroid Capture Mission

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Since 2012, NASA has been trying to figure out how to capture an asteroid and bring it back to Earth. This is a good idea for a bunch of reasons, but there aretwo big ones (according to NASA). First,the mission will help develop technologies that could be used to redirect an asteroid thats on a collision course with Earth.And, second,snagging an asteroidand dragging it into lunar orbit so a manned spacecraft can poke around itwill be a useful way to prepare humans for deep-space travel, eventually, to Mars.

Last week, NASA announced a much more detailed plan of exactly what this asteroid redirect mission will entail. As expected, its a bit more conservative than the original concept for the mission, but with (the agency hopes) a substantially better chance of success.

NASA's original idea was to go out and find a near-Earthasteroid with a diameter of about 8 meters and a mass of about 500 metric tons, which, for the record, isnot big enough to make it through Earths atmosphere intact. Once the spacecraft got to this asteroid, it would capture it inside a giant container of some sort (a net or bag), and then haul it back towards Earth.

The problem with this approach is thatits a one-shot deal: if the capture container fails for some reason, thats it, youre done, and the two year, US $1.25-billion mission amounts to something depressingly close to zilch. Instead, NASA has scaled back the Asteroid Retrevial Mission (ARM) into aTiny Little Piece of an Asteroid Retrevial Mission (TLPARM). Rather than trying to grab an entire asteroid all at once, NASA's spacecraft will arrive witha giant claw. After scouting the asteroid for up to 400 days, NASA will choose a likely looking boulder (3m or so in diameter), and then play the most expensive claw game ever to try and land the spacecraft right on top of it and make the snag. NASA speculates that theyll have between three and five quarters tries.

That bit at the end abouttransitioning toplanetary defense demonstration means using the spacecraft (with the boulder in tow) as a gravity tug.

A gravity tug is a really niftyway of changing the trajectory of something massive (like an asteroid) using something small (like a spacecraft). Everything is effected by the gravity of everything else, and if you sticka spacecraft near an asteroid, the asteroid is going to get pulled a little tiny bit towards the spacecraft. The spacecraft is going to have to deal with a much stronger pull from the asteroid, of course, but the spacecraft has thrusters to compensate for that, and the asteroid doesnt.

The amount of pull that the gravity of a spacecraft that weighs a few tons has on an asteroid that weighs hundreds or thousands of tons is barely noticeable (hundredths or thousandths of a newton), but it's there. Given enough time (like, decades), the spacecraft could nudge the asteroid enougha change in velocity of perhaps one centimeter per secondto make the difference between obliterating the Earth and a near miss that wed probably not even bother to blog about.

To test out this concept, NASA will have its ARM spacecraft orbit the asteroid just ahead of its center of mass, which should ever so slightly pull the rock towards the spacecraft. As a bonus, this will be after the spacecraft picks up the rock, since more mass on spacecraft plus less mass on asteroid equals everything working that much better. Once NASA has determined whether this gravity tug idea works well in practice, the spacraft (with rock in grasp) will make its way into a lunar orbit over the course of about six years.

In order to get the level of propellant efficiency that a mission like this requires, NASA will be relying on Solar Electric Propulsion (SEP), or more specifically, Hall effect thrusters. Until someone figures out how to convert energydirectly into thrust, SEP is one of the most efficient and reliable ways of propelling a spacecraft. Rather than relying on messy chemical reactions, Hall thrusters use electricity (harvested from solar panels) to accelerate xenon ions through a charged grid. The electricity is renewable, and since all (or, almost all) of the propellant gets turned into thrust as opposed to heat or other byproducts, SEPs efficiency is hard to beat.

The downside of SEP is that just tossing xenon out the back of your spacecraft isn't going to generate a huge amount of thrust, even if each xenon ion is reaching the ludicrious speedof 30km/s. A 10 kilowatt Hall thruster (NASA is planning on using four of these on the asteroid redirect spacecraft, plus one spare) can probably produce about 500 mN of thrust, or about the weight of 50 business cards. If you're fighting gravity, this is nothing, but if you're in space, its plenty, as long as you can keep your engines going for a very long time. And this is where SEP shines: the specific impulse of these Halleffect thrusters is3000 seconds.

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NASA Details 2020s Asteroid Capture Mission