LOADING...
Text Size
Chasing Down an Asteroid
August 27, 2013

[image-51]

[image-76]

[image-90]

[image-104]

Home of U.S. human spaceflight control leads mission planning

“This is Mission Control, Houston.”

Almost everyone defines these five words with one place and one meaning: NASA’s Johnson Space Center, home of U.S. human spaceflight.

It is along these sidewalks and within these buildings that planning already is underway to send astronauts farther than they have ever gone before. This time to retrieve samples from an asteroid that almost certainly is made up of ingredients from the early solar system.

The Johnson-led team is putting the pieces together for a 24 to 30-day mission culminating in the return of samples from an asteroid placed in a stable lunar orbit waiting to be harvested.

The building blocks and creativity for designing such a mission is located at one place on Earth – here at Johnson. Shaping those blocks into a mission leading to an asteroid really began almost 50 years ago when the center opened to cradle America’s human spaceflight training and flight control activities.

“For Johnson this mission represents a rally point for our exploration endeavors,” said Steve Altemus, former center deputy director. “Whether it is in expediting the completion of Orion or developing the necessary technologies for extended missions in deep space. We at Johnson are crucial to making this mission and future exploration missions successful.”

Before stepping in as deputy in January, Altemus led the team tasked with designing a mission flight plan with all the supporting knowledge and techniques that reside at Johnson as world leader in human spaceflight operations.

It is just this type of mission that showcases the talents of experts in the field of human space exploration and offers something for everyone who believes low-Earth orbit is a waypoint for understanding what it takes to go farther than humans ever have previously.

NASA’s newest spacecraft under development is known by the name Orion, but it is the accompanying acronym – MPCV – that defines its mission: Multi-Purpose Crew Vehicle. It is surrounding those first two simple words where the story of a human mission to an asteroid begins.

Finding an asteroid worthy of capture and study has long been studied – most recently by the Keck Institute for Space Studies at the California Institute for Technology in Pasadena. It was there in 2012 that a team conceived of a five-year robotic mission to capture a million-pound asteroid and return it to a lunar orbit so stable that it could remain there for as much as a hundred years without any propulsive maintenance required. This location is known as a distant retrograde orbit – one that traverses more than 43,000 miles beyond the moon.

It is here that the human interaction aspect of a mission to an asteroid suddenly moves from futuristic wish-list item to one that actually can be accomplished using the ingenuity of the people that have sustained a steady U.S. presence in space on six different spacecraft for almost 50 years.

As 2012 wound down, the team studying Orion missions was asked to focus its efforts and resources on the feasibility of a flight to the far side of the moon where an asteroid in the size range of 20-30 feet would be waiting.

Leaders at NASA’s headquarters in Washington knew of the “Keck Study” and thought that sending astronauts to an orbit closer to Earth could be much more practical from a cost and calendar standpoint than going directly to an object so far away that a crew could be gone for a year or more.

Steve Stich, JSC Engineering deputy director and expert in flight dynamics and human spaceflight, has led the human mission development since January.

“We were asked by leaders at headquarters to utilize our Concept Analysis Team at Johnson to determine whether we could pull off a human mission to an asteroid to obtain samples in a very lean, affordable fashion using only two launches. That was in the late December timeframe,” Stich said.

“Over the last seven months, our engineering teams have concluded that this bold mission is technically feasible and that Orion is, in fact, the perfect vehicle to fly the ambitious trajectories required, dock with the robotic spacecraft containing the asteroid, and execute the two spacewalks. We recently completed a very successful Mission Formulation Review at headquarters July 30 chaired by Associate Administrator Robert Lightfoot and senior NASA leaders agreed with our conclusions,” Stich continued.

At the time the mission study was formally proposed as part of NASA’s fiscal 2014 budget request, various missions were being studied for early Orion flights combined with its huge booster rocket known as the Space Launch System (SLS), whose design and development is being led from the Marshall Space Flight Center in Huntsville, Ala.

From its beginnings, Orion was envisioned as a long-duration, deep-space human transport capable of missions far more distant than any other spaceship ever built. With missions lasting longer than six months being considered, Orion’s design is robust enough to sustain a crew for just about any conceived mission.

And the most comprehensive, yet audacious mission is the one proposed: send a crew to rendezvous with an asteroid, conduct spacewalks to retrieve samples, and return safely to Earth to conclude an approximate three-week mission.

Veteran astronaut Andy Thomas has been on the team from the beginning. He is no stranger to spaceflight – short or long duration – having flown aboard four space shuttle missions to two different space stations. He was the last astronaut to live on the Russian Mir in 1998 and has first-hand knowledge of spacewalking. He definitely believes in traveling the space highways beyond where we’ve been so far.

“I’ve been a big proponent of getting the agency to focus its human spaceflight efforts away from low-Earth orbit and looking beyond the International Space Station and what we’re going to do next – particularly going out into deep space,” Thomas said, adding that he believes there are ways to do it “that are technically viable, financially viable, politically acceptable and which make sense without breaking the bank.”

The latest in planning now proposes sending the first uncrewed Orion space capsule to this region on a similar duration flight to serve as an early pathfinder mission to verify capsule ability and integrity to support a human flight later.

"We sent Apollo around the moon before we landed on it and tested the space shuttle's landing performance before it ever returned from space." said Dan Dumbacher, NASA's deputy associate administrator for exploration systems development. "We've always planned for Exploration Mission-1 to serve as the first test of SLS and Orion together and as a critical step in preparing for crewed flights. This change still gives us that opportunity and also gives us a chance to test operations planning ahead of our mission to a relocated asteroid."

Either way, expertise across Johnson’s 1,600 acres is being drawn upon to put a mission together that most certainly will be one for the history books.

Norm Knight knows firsthand what that expertise is capable of doing. He leads the Flight Director Office having worked his way up from an entry level position. His intensity and enthusiasm is infectious as he describes the Asteroid Redirect Mission and the years of experience in previous programs that permeates directorates here.

“Training the crew and flight control team to be able to perform this mission, defining the mission objectives and pulling together the integrated team to achieve them, and looking ahead to identify what the potential hurdles and obstacles are in the real-time environment – Johnson is where the expertise resides to put this mission together,” Knight said.

His role on the team is to pull the mission operations big picture together using the same people that pieced together intricate shuttle missions – and those that assembled and now provide full-time support for the International Space Station. In concert with the engineering design experts, mission operations essentially pieces the mission together long before it is ever flown.

“Identifying the ‘what ifs’ early in the design cycle is critical before we actually go fly any mission for real. This allows change to the vehicle and mission design as a function of operational risk management, thus increasing crew safety and the ability to achieve the mission objectives. When we leave to accomplish this asteroid mission, we will have already thought through many of those ‘what ifs,’ which also prepares the team for the unexpected scenarios that spaceflight presents.”

Knight sits alongside Kirk Shireman, who also is no stranger to the mission operations philosophy at Johnson. Shireman recently was named to replace Altemus as deputy director when the latter announced his departure.

Shireman leaves the deputy station program manager position where he has seen the largest orbiting spacecraft evolve from a design on paper to an operational science laboratory staffed by astronauts and cosmonauts for nearly 12 years continuously. If we want to leave low Earth orbit with a crew, he knows what it will take.

“The asteroid redirect mission will test Orion, the Space Launch System, and a high-power solar electric robotic spacecraft. This is a great opportunity to further both human spaceflight by testing out these exploration elements, while also supporting planetary science by retrieving samples from an asteroid. The space station will play a role in this effort, by helping to mature some technologies used on Orion and also testing some of the mission kits before they are used on the retrieval mission,” Shireman said.

Eight years ago this past July, Thomas flew aboard Space Shuttle Discovery on the STS-114 mission, which served as the Return To Flight following the loss of Columbia. That was his last spaceflight, but not his last ‘mission.’

Serving as the voice of the Astronaut Office to the human asteroid mission team with eloquence and determination, Thomas said if people look at this mission closely, it has something for everyone.

“If you believe that we should be going back to the Moon, this mission gets a human presence in lunar space for the first time in 50-plus years. It would teach us how to navigate around the moon, how to work in trans lunar space, and would re-establish a human presence around the moon. So if you believe we should go to the moon, you should jump on this mission because it’s a pathway there.”

But that’s just one benefit of heading to the farside of the moon. Listening to Thomas describe the future benefits of this mission, you will hear his passion and belief in pursuing the flight.

“This mission teaches us how to work and operate Orion in deep space. It will teach us how to use SLS. If you believe we should be using this as an interventional mission to Mars, this is a step in that direction. If you are an asteroid fan and believe we absolutely have to do something about planetary defense, this is a mission for you, because it teaches us how to go up to one of these uncooperative rocks, how to interact with it, how to attach to it, and all the things that you may need for planetary defense. So it’s got something for that community.”

Certainly mission operations are a critical component of making a spaceflight of this complexity a reality. But the reason for it is to gain firsthand scientific data from a time capsule of the early solar system.

This type of mission holds uncertainties, which almost assuredly are what make it the most attractive and the most challenging to the workforce.

Whoever the crew members will be for this mission likely are already on the payroll and the years between now and launch will allow them to have gained spaceflight experience.

Thomas imagines being on that flight.

“From a crew perspective it would be a great flight. It would. Because you’d launch on SLS, take a few days to get to the moon and do this low lunar fly-by. You go screaming around the moon firing your engines to get a gravity assist out to this distant orbit. You then do a firing to get into the orbit. You then fly up to this object, rendezvous and capture it. Imagine the view you’d have: You’d have the moon 70,000 kilometers below you and then way off in the distance you’d have the Earth. It would be spectacular. It really would.”

Although a human mission to that distance from Earth has never been done, the expertise to plan it already is in place. Flexibility is key at that distance because there will be unknowns associated with the asteroid.

And there will have to be serious design discussions to protect for system redundancy, or robustness since a return home in the event of an issue is counted in days rather than hours as it is now.

But that’s the exact type of mission to be flown beyond an asteroid lassoed and transported closer to Earth. Mars is further. Much further.

The risk discussion takes center stage and years of expertise help understand and manage the risks.

How much is invested of human capital dollars in order to get to a level of risk that’s acceptable to perform the mission is the question, and a difficult problem.

As Thomas puts it, “It’s an engineering challenge and it’s a human challenge.”

Mission planners are faced with measuring the flight every step of the way. The day of launch, orbital mechanics dictates the crew is roughly 21 days from home. Halfway through the mission, it is 10 days from home. When missions eventually go further on to Mars, system reliability has to be very high. The consequences of a catastrophic failure are unthinkable.

Johnson is leading the effort to understand what human deep space mission design is all about. This mission is the next step in that direction.

Image Token: 
[image-36]
Youtube Override: 
jXvsi7DRyPI
Concept animation featuring notional crew operations during NASA's proposed Asteroid Redirect Mission
Image Credit: 
NASA
Image Token: 
[image-51]
This conceptual image shows NASA’s Orion spacecraft approaching the robotic asteroid capture vehicle. The trip from Earth to the captured asteroid will take Orion and its two-person crew an estimated nine days.
Image Credit: 
NASA
Image Token: 
[image-76]
In this conceptual image, the two-person crew uses a translation boom to travel from the Orion spacecraft to the captured asteroid during a spacewalk.
Image Credit: 
NASA
Image Token: 
[image-90]
This concept image shows an astronaut preparing to take samples from the captured asteroid after it has been relocated to a stable orbit in the Earth-moon system. Hundreds of rings are affixed to the asteroid capture bag, helping the astronaut carefully navigate the surface.
Image Credit: 
NASA
Image Token: 
[image-104]
Page Last Updated: August 27th, 2013
Page Editor: Jason Roberts