14 August 2010

Experts Weigh in on Human Mission to an Asteroid

From: http://news.yahoo.com/s/space/20100809/sc_space/expertswillweighinonhowtoputhumansonanasteroid

Experts Will Weigh In On How to Put Humans On an Asteroid
  Jeremy Hsu
Space News Senior Writer
SPACE.com jeremy Hsu
space News Senior Writer
space.com – Mon Aug 9, 1:15 pm ET

A visit by humans to an asteroid may take a step closer to reality at a NASA workshop this week.

A spirit of excitement is bubbling over NASA's new aim, not unlike when the agency first aimed to land a man on the moon, NASA's Laurie Leshin said ahead of the two-day session, set for Tuesday and Wednesday in Washington, D.C.

Planetary defense against killer space rocks also has a place on the agenda.

The human exploration of a near-Earth object would rely upon the experiences of robotic expeditions like Japan's Hayabusa mission, which recently returned to Earth with particles that may be asteroid samples.

Experts and leaders from government, academia, industry and the international community are expected to weigh in on what would be required to stage a mission to a near-Earth object, according to Leshin, deputy associate administrator of NASA's Exploration Systems Mission Directorate.

"Between Kennedy's speech at Rice and Neil Armstrong's first steps, there were a lot of meetings like this," Leshin told SPACE.com. "We are excited to begin to bring together the range of ideas that exist for human exploration of NEOs and start to focus them on a plan forward."

In 1962, President John F. Kennedy gave his historic speech at Rice University discussing the goal of putting an American on the moon by the end of the decade. It came one year after he announced the goal to Congress. Armstrong commanded the first manned moon landing mission, in July 1969.

The new goal of sending astronauts to land on asteroids is part of President Barack Obama's plan for the future of the National Aeronautics and Space Administration. Obama announced the new direction for NASA in April, two months after proposing a 2011 NASA budget that included the cancellation of the agency's moon-oriented Constellation program.

The Congress is still discussing NASA's 2011 budget (the House is expected to revisit the issue next month), but that hasn't stopped scientists from taking a look at what a manned mission to an asteroid would entail.

That's where this week's workshop comes in.

Goals for the meeting include boosting the collective understanding of NEOs and laying out NASA's plans for the human mission. NASA also hopes to collect outside input on any proposed mission objectives and identify any gaps in technology or know-how.

Regarding planetary defense, experts would consider questions such as what remains unknown about NEOs and what technologies could be used to stop objects that pose a threat to Earth. A NASA panel recently called for the creation of a Planetary Defense Coordination Office and suggested making planetary defense a top-level NASA strategic goal.

The meeting also will consider whether a human mission to an NEO could work in tandem with a mission to the moon or Mars. Obama's current plan for NASA would focus on ambitious heavy-lift rockets to carry astronauts beyond low-Earth orbit to an asteroid and Mars.

    * Images — Asteroids Up Close, Astronauts on Asteroids
    * NASA's New Asteroid Mission Could Save the Planet
    * Will an Asteroid Hit Earth? Are We All Doomed?

This story has been corrected to reflect that President Kennedy first announced the intent to send astronauts to the moon in May 1961, then discussed the plans at Rice University in September 1962.

Find the actual workshop schedule and presentations here:

Here is the NASA statement:
Exploration of Near Earth Objects (NEO) Objectives Workshop [Explore NOW]
August 10-11, 2010
Washington, DC

NASA hosted an interactive, two-day workshop to identify objectives for exploration missions to Near Earth Objects (NEOs). The meeting was conducted August 10-11 at The Mayflower Renaissance Hotel in Washington, D.C.
The primary goals for the workshop were: to increase the collective understanding of NEOs, communicate NASA's plans for a human mission to a NEO, and capture external input on proposed mission objectives.
Explore NOW brought together experts and key leaders within NASA, industry, academia, other government agencies, and international communities.
Download presentations and reference materials:
+ View the workshop schedule and download presentations.
+ View a list of workshop reference materials available for download.
Send comments:
+ Submit your comments and questions on the breakout session topics now.

 A Planetary Society participant blogger Bruce Betts recorded his observations of:

Day 1: http://planetary.org/blog/article/00002617/

Day 2: http://planetary.org/blog/article/00002619/

As did a Quantum G blogger: http://quantumg.blogspot.com/2010/08/asteroid-menace.html
(This blogger gets a few things wrong.  Humans can be additive, but most planetary defense thinkers do not think human beings are essential to the task, and the primary means of deflection or Kinetic Impactors, Nuclear Standoff Explosives, and the Gravity Tractor)

Day one of the Exploration of Near Earth Objects Objectives Workshop saw the presentation of three key reasons to send humans to visit asteroids: science, mining and planetary protection. Of these, the last has has been shown to be an issue that attracts mainstream support, no doubt we have Bruce Willis to thank for this.

The workshop began with presentations of the robotic missions that have been flown to asteroids and comets. The recently returned sample return mission Hayabusa, taking pride of place. All the presenters had war stories of the operational difficulty of flying to these objects, and some expressed surprise that their missions succeeded at all. They also talked about the high cost of these missions in terms of remote sensing equipment and the lack of good ground truth information to calibrate these instruments.

Unsurprisingly then, they all support a human mission to an asteroid or a comet near Earth to more efficiently gain scientific results. However, when asked about planetary defense, the consensus opinion wasn't just that a human mission would be nice: it is absolutely necessary.

Here's some interesting audio from the workshop.

An asteroid is heading to Earth that will kill every one of us, someday. Hopefully we will discover it and track it for long enough to have 5 or 10 years prior notice. Now what? We'd love to send a robotic probe to get some idea of what the object looks like, what it is made of, how fast it is rotating, etc. Unfortunately, a robotic mission will take at least 5 years to go from concept to launch and it has a very low chance of success at even this precursor mission. Sending a robotic mission to deflect or otherwise mitigate the threat is simply unthinkable at this time....

That means we need to send humans, and it means we need to send them to meet the threat with no robotic precursor. The astronauts will do the scientific investigation to determine the composition of the object. This will most likely include planting seismic detectors, and launching one or more kinetic impactors into the surface. Relaying this data back to Earth, the astronauts would wait for ground control, probably with the support of the national laboratories, to decide on a mitigation plan. Obviously the plan will be limited by what the astronauts have with them, so they will need to carry an array of tools for the various types of threats that may be expected.

For example, the best strategy may be to install large motors which provide constant thrust for a period of years diverting the asteroid off course just enough to miss the Earth. Such a strategy would only be possible on objects where in-situ resource utilization could produce sufficient propellant. Another strategy may just be the placement of a station keeping spacecraft with a lot of mass, possibly removed from the surface of the object, to act as a "gravity tractor", again diverting the course away from Earth. More exotic strategies may include converting rotational energy into propulsive energy using long tethers or in the drastic use of nuclear bombs.

The workshop continues today and is being webcast. Ultimately, failure to send astronauts to visit near-Earth objects within the next few decades will be fatal to humanity, so tune in and participate.