[/caption] Note: To celebrate the 40th anniversary of the Apollo 13 mission, for 13 days, Universe Today will feature “13 Things That Saved Apollo 13,” discussing different turning points of the mission with NASA engineer Jerry Woodfill.
When the oxygen tank exploded on the Apollo 13 Command Module, the astronauts on board and everyone in Mission Control had no idea what the problem was. In his book, “Lost Moon,” Apollo 13 commander Jim Lovell thought the “bang-whump-shudder” that shook the spacecraft could have been a rogue meteor hit on the lunar module, Aquarius. Quickly, he told Jack Swigert to “button up” or close the hatch between the Command Module Odyssey, and Aquarius, so that both spacecraft wouldn’t depressurize.
But the hatch wouldn’t close.
Apollo engineer Jerry Woodfill believes the balky hatch was one of the things that helped save the Apollo 13 crew. “They were trying to close off the only way they could save their lives,” he said.
In Mission Control and in the nearby Mission Evaluation Room, several engineers, including Woodfill, thought the only explanation for so many systems to go offline at once was an instrumentation problem. “Initially I thought there was something wrong with the alarm system or the instrumentation,” said Woodfill, who helped develop the alarm system for the Apollo spacecraft. “There was no way so many warning lights could illuminate at once. I was sure I would have some explaining to do about the system.”
At first, Lovell thought Fred Haise may have been playing a joke on the crew by actuating a relief valve that made a sort of popping noise – something he had done previously during the flight. But with the surprised look on Haise’s face, along with the noise and all the alarms going off, Lovell’s next thought was the hull had been compromised in Aquarius.
Like a submarine crew that closes hatches between compartments after being hit by a torpedo or depth charge, Lovell wanted to close the hatch into the Command Module so all the air didn’t rush out into the vacuum of space.
Swigert quickly tried three times to close the hatch, but couldn’t get it to lock down. Lovell tried twice, and again couldn’t get it to stay closed. But by that time, Lovell thought, if the hull had been compromised, both spacecraft surely would have already depressurized and no such thing was happening. So, the crew set the hatch aside and moved on to looking at the falling gauges on the oxygen tanks.
And shortly after that, Lovell looked out the window and saw a cloud of oxygen venting out into space.
Earlier in the flight, the Apollo 13 crew had opened the hatches between Odyssey and Aquarius, and actually was far ahead on their checklist of preparing to land on the Moon by turning on equipment in the lander.
Woodfill believes this was fortuitous, as was the hatch not closing, because saving time was of the essence in this situation.
“Some people say that doesn’t amount to much time,” Woodfill said, “but I say it did, because if they had closed and latched up the hatch, and then worked to find the real problem of what was wrong, then they would have to delay and quit working the problem to go remove the hatch, stow the hatch and go power up the lander.”
Why was time so important?
The fuel cells that created power for the Command Module were not working without the oxygen from the two tanks. “Tank 2, of course, was gone with the explosion,” said Woodfill,” and the plumbing on Tank 1 was severed, so the oxygen was bleeding off from that tank, as well. Without oxygen you can’t make the fuel cells work, and with both fuel cells gone they know they can’t land on the Moon. And then it became a question of whether they can live.”
But over in Aquarius, all the systems were working perfectly, and it didn’t take long for Mission Control and the crew to realize the lunar module could be used as a lifeboat.
However, all the guidance parameters which would help direct the ailing ship back to Earth were in Odyssey’s computers, and needed to be transferred over to Aquarius. Without power from the fuel cells, they needed to keep the Odyssey alive by using the reentry batteries as an emergency measure. These batteries were designed to be used during reentry when the crew returned to Earth, and were good for just a couple of hours during the time the crew would jettison the Service Module and reenter with only the tiny Command Module capsule.
“Those batteries are not ever supposed to be used until they got ready to reenter the Earth’s atmosphere,” said Woodfill. “If those batteries had been depleted, that would have been one of the worst things that could have happened. The crew worked as quickly as they could to transfer the guidance parameters, but any extra time or problem, and we could have been without those batteries. Those batteries were the only way the crew could have survived reentry. This is my take on it, but the time saved by not having to re-open the hatch helped those emergency batteries have just enough power in them so they could recharge them and reenter.”
It’s interesting when the hatch had to work correctly, when the lander was jettisoned for re-enty, it worked perfectly. But at the time of the explosion, it’s malfunctioning kept the pathway to survival into the LM open, saving time. Being able to get into the lunar lander quickly was what helped save the crew’s life.
Tommorow: Part 3: The measles
Additional articles from the “13 Things That Saved Apollo 13”
Note: To celebrate the 40th anniversary of the Apollo 13 mission, for the next 13 days, Universe Today will feature “13 Things That Saved Apollo 13,” discussing different turning points of the mission with NASA engineer Jerry Woodfill. Click here for our preview article.
Oxygen Tank two in the Apollo 13 Service Module exploded at Mission Elapsed Time (MET) 55 hours and 55 minutes, 321,860 kilometers (199,990 miles) away from Earth. If the tank was going to rupture and the crew was going to survive the ordeal, the explosion couldn’t have happened at a better time. “Not everyone agrees with all the things I’ve come up with in my research,” said NASA engineer Jerry Woodfill who has studied the Apollo 13 mission in intricate detail, “but pretty much everyone agrees on this, including Jim Lovell. The timing of when the explosion happened was key. Much earlier or later in the mission would have prevented a successful rescue.”
If the explosion happened earlier (and assuming it would have occurred after Apollo 13 left Earth orbit), the distance and time to get back to Earth would have been so great that there wouldn’t have been sufficient power, water and oxygen for the crew to survive. Had it happened much later, perhaps after astronauts Jim Lovell and Fred Haise had already descended to the lunar surface, there would not have been the opportunity to use the lunar lander as a lifeboat.
But looking at why the explosion happened when it did shows how fortuitous the timing ended up to be.
The explosion occurred when Jack Swigert flipped a switch to conduct a “stir” of the O2 tank. The Teflon insulation on the wires to the stirrer motor in O2 tank 2 had unknowingly been damaged because the manufacturer failed to update the heater design for 65 volt operation, and the tank overheated during a pre-flight test, melting the insulation. The damaged wires shorted out and the insulation ignited. The resulting fire rapidly increased pressure beyond its nominal 1,000 psi (7 MPa) limit and either the tank or the tank dome failed.
The O2 tanks were stirred in order to get an accurate reading on the gauging systems, as the cryogenic oxygen tends to solidify in the tanks, and stirring allows for a more accurate reading on the quantity of O2 remaining in the tank.
But this was not the first time the crew had been ordered to stir the tank. It was the fifth time during the mission. And most interestingly, the tanks normally were stirred approximately once every 24 hours. So, why was it stirred that often?
In what Woodfill said was a problem unrelated to what caused the explosion, the quantity sensor or gauge was not working correctly on O2 tank 2. The EECOM (Electrical Environmental and Consumables) flight controller in Houston discovered that the quantity sensor was not reading accurately, and because of that Mission Control asked the astronauts to perform additional actuations of the stirrer to try and troubleshoot why the sensor wasn’t working correctly.
So, it took five actuations until the short circuit and the resulting fire and explosion occurred. If the gauge had been working correctly and the normal stirring of the tank had been done, that would have put the time of the fifth stirring after Lovell and Haise had departed for the lunar surface, and the rescue scenario that ultimately was carried out couldn’t have happened.
“Check the arithmetic,” said Woodfill. “Five actuations at 24 hour periods amounts to a MET of 120 hours. The lunar lander would have departed for the Moon at 103.5 hours into the mission. At 120 hours into the mission, the crew of Lovell and Haise would have been awakened from their sleep period, having completed their first moon walk eight hours before. They would receive an urgent call from Jack Swigert and/or Mission Control that something was amiss with the mother ship orbiting the Moon.”
Who knows what would have happened to the crew? The fuel cells required the liquid oxygen tanks. This meant no production of electrical power, water and oxygen. The attached lunar lander had to be available. Likely, the two ships couldn’t even have docked back together. And what if the accident had happened behind the Moon without mission control’s help? Alone in the Command module, Swigert would have had difficulty analyzing the problem. Without a fueled lunar lander descent stage attached, lacking its consumables and engines as well as the needed battery power, water and oxygen, the crippled Command Module could not have returned to Earth with live astronaut(s). Not only would Lovell and Haise have perished but Swigert’s fate would have been the same. Even if the damaged Service Module’s engine had worked, no fuel cells meant the ship would die. The situation that the Apollo 13 crew actually faced was dire, but the alternative scenario would certainly have been fatal.
Woodfill contends that the quantity sensor malfunction assured the lunar lander would be present and fully fueled at the time of the disaster. It was an extremely fortuitous event. Had it not occurred, the timing of the explosion would have been far different and the crew would have perished.
Additional Articles from the “13 Things That Saved Apollo 13” series that have now been posted:
Everyone seems to be a little confused and in the dark about the direction NASA will be headed if Obama’s proposed FY2011 budget passes. Yesterday’s hastily called press briefing answered a few question, but not the big issues of where we’ll be going and how we’re going to get beyond low Earth orbit. Yes, Bolden did say that Mars is the ultimate destination but everyone knows we can’t just pick and go to Mars. NASA needs a vehicle to get there, and getting there will require doing it in incremental steps, such as going to the Moon or asteroids first. There’s no plan (yet) for a vehicle and no plans for those incremental steps. Hopefully Obama’s “Space Summit” on April 15 will provide some answers.
I’m of two minds about this whole deal.
First, I love the space shuttle. I’ve just spent two months at Kennedy Space Center. I experienced the launch of Endeavour, got to see Endeavour and Discovery up closer than I ever imagined, saw behind the scenes processing, met people who work with the shuttles every day, and talked with people whose livelihood depends on NASA sending people to space.
And admittedly, any talk of extending the shuttle program makes my heart leap just a little. It’s a beautiful, marvelous, incredible machine – many say the most complex device ever invented by humans. And why shouldn’t we keep flying it? NASA managers like Mike Moses, Mike Leinbach and John Shannon say that since the Columbia accident we now know the shuttle and understand the risks better than ever. Right now, it definitely would be safer to fly on a shuttle than to fly on a new, untested commercial rocket.
And the jobs lost – not only at KSC but at Johnson Space Center, other NASA centers and contractors — by ending the shuttle and canceling Constellation means individuals who have these incredible skill sets for getting people to space may not be needed anymore. There are things they know that just can’t be replaced, replicated or restarted five or ten years down the road.
Bolden said yesterday that there should be new jobs under the new budget which provides more money for NASA, but nobody really knows yet how many and where.
One of the most poignant questions asked by a reporter at yesterday’s press briefing came at the very end: What’s to say that when a new administration enters the White House that we won’t come back to starting over again with a whole new program?
“If we execute the budget as proposed and prove that we are on a sustainable path, that is the best protection for a subsequent administration not having to change course,” said Lori Garver, Deputy NASA Administrator. “That’s the goal, to not be in this position every four years. These technologies we will be developing will allow us to leave low Earth orbit and go to interesting places. We’ll be able to determine the best places to go, and we should have the data to do it and the capabilities to do it that are more affordable, which has been the goal since the beginning to the space program.”
So this is where my other mind kicks in.
Change is hard. It’s really hard when people’s lives and livelihood are affected. But without change, we get comfortable and getting comfortable means we do the same things over and over.
Running NASA the same way ever since the end of Apollo, while giving us the amazing vehicle that is the space shuttle, has not gotten humans beyond low Earth Orbit, and I think everyone agrees we want to be able to go other places.
Last year NASA turned 50 and there were some comments about NASA reaching middle age and acting like it, too. Change is what keeps us young, and change keeps us on our toes. When you’re willing to change and get out of your comfort zone, you make a commitment to the unknown. And that’s what NASA should be all about. Our memories can’t be bigger than our dreams.
Perhaps the hardest thing about these proposed changes to NASA is that Obama and Bolden are asking for change without telling us exactly what the change is. Maybe they don’t know yet, but this is something we can’t just figure out along the way.
There’s the famous saying that life is not about the destination but the journey, or the other saying that the best thing about being in a race is competing in it. But most journeys have a map and most races have a finish line.
If the proposed budget and plan goes through, this will give us a shot at journeying beyond. Now we just need to know where we’re going and how we’re going to get there.
I started writing this to report on yesterday’s briefing by Charlie Bolden, Lori Garver and other NASA officials, but clearly it turned into something different. Here are a few links to articles by other journalists who wrote about the briefing and what might be coming next:
The debate on why humans should or should not return to the Moon has been ongoing for years. Two weeks ago, I had the opportunity to hear astronautRon Garan speak eloquently on a subject he is passionate about, water sustainability on planet Earth. Subsequently, I read an essay Garan wrote about the importance of returning to the Moon. Although Garan originally wrote this essay before the cancellation of the Constellation program was announced, he has amended his thoughts to reflect the likelihood that the US won’t be returning to the Moon anytime soon. With Garan’s permission, we are re-publishing his essay in its entirety.
The Importance of Returning to the Moon
(The 8th Continent)
By Ron Garan
On May 10th, 1869, a golden spike joined two railways at Promontory Point, Utah, and the first transcontinental railroad was completed. On January 14th, 2004, a new vision for our Nation’s space exploration program was announced that committed the United States to a long-term human program to explore the solar system starting with a return to the moon. On February 1st 2010, those plans to return to the moon were put on hold. Although our Nation has decided to postpone a return to the moon it is still important to acknowledge the moon’s relevance to life on Earth.
There is no doubt that the railroad changed the world. It opened up frontiers to discovery, settlement, and commerce. The railroad was the backbone for the industrial revolution that provided the largest increase in life expectancy and improvement in quality of life in history. Just as the industrial revolution brought about unprecedented improvements in quality of life so can a new age of space exploration and development, but this time with a positive impact on the environment. To begin a period of sustainable space exploration, both the public and private sectors of our Nation must seize the opportunity and continue on a path to the moon.
Since the Vision for Space Exploration was announced in 2004, there has been an on-going debate about the importance of taking the next step in space exploration, a return to the moon. The reasons for making this the next step include: fulfilling a compelling human need to explore; gaining a foothold on the moon to prepare for journeys to other worlds; easing the world’s energy problems; protecting the planet from disasters; creating moon-based commercial enterprises that will improve life on Earth, conducting scientific research; inspiring young people toward higher education, and utilizing space resources to help spread prosperity throughout the world.
We should not return to the moon for any one of these reasons, but for all of them and more. By first establishing the basic infrastructure for a transportation system between the Earth and the moon and a sustainable, semi-autonomous, permanent human settlement, we will open the door to significant benefits for all. Of course, any permanent lunar base must be economically and politically sustainable and therefore must provide tangible benefits and a return on investment.
Exploration: Great nations accomplish extraordinary endeavors that help to maintain their leadership in the world. America’s history is built on a desire to open new frontiers and to seek new discoveries. NASA’s vision for space exploration acknowledges that, “Mankind is drawn to the heavens for the same reason we were once drawn into unknown lands and across the open sea. We choose to explore space because doing so improves our lives and lifts our national spirit.”
Establishing a lunar infrastructure will challenge us to improve the reliability of space transportation and allow us to demonstrate exploration systems and concepts without leaving the relative safety of near-Earth space. Testing systems and concepts at a location that’s a three-day journey from Earth is a logical step before we make the leap of a six-month journey to Mars. Establishing a permanently occupied lunar base also will open the way to detailed study and use of lunar resources, which likely are significantly more economical than lifting all required exploration resources from the Earth’s surface.
Energy: Today, about 1.6 billion people on the Earth don’t have access to electricity. The World Bank estimates that 1.1 billion people live in extreme poverty which leads to 8 million premature deaths every year. In developed countries, higher quality of life is achieved only through a high rate of energy use. Increased energy supply is needed for economic and social development, improved quality of life, and to grow enough food to provide for the citizens of the developing world.
Unless something is done soon, the world will be faced with a crisis of enormous proportions. The United Nations estimates that world population will be approximately 9.1 billion by 2050 with virtually all growth in the 50 poorest countries. The choices that the global society makes to provide for future energy needs will have a profound effect on humanity and the environment.
The moon can supplement Earth-based renewable energy systems to meet future energy demand. Ample energy from the Sun reaches the moon and is not interrupted by weather, pollution or volcanic ash. Solar energy farms on the moon can “beam” limitless clean energy down to where it is needed on Earth or to satellites for relay to the Earth. There are also other potential sources of energy including platinum for fuel cells and an isotope called helium-3, which could be used in fusion reactors of the future.
Supplying energy from the moon will enable us to help provide the Earth’s energy needs without destroying our environment.
Protect the Planet from Disasters: There is a real risk to the Earth’s inhabitants from asteroid impacts and super-volcano eruptions. If a large object the size of Comet Shoemaker-Levy 9 that recently slammed into Jupiter were to hit the Earth, civilization could be destroyed. Much smaller asteroids could cause tremendous damage and loss of life. The moon is a superb location for early detection systems.
A super-volcano eruption is a geologic event of enormous explosive power to affect the global climate for years. Scientists estimate the last such eruption happened 74,000 years ago, and was 10,000 times more powerful than Mount St. Helens. Tremendous amounts of rock and ash were ejected into the air causing a six year long volcanic winter and a 1,000-year instant Ice Age, massive deforestation, disastrous famine, and near extinction of humankind. Scientists estimate that such a super-eruption will occur about once every 100,000 years.
The systems and technology that will be developed for life and work on the moon can be used to develop habitats and systems that could preserve Earth’s inhabitants in the event of a devastating eruption. These systems will also improve our ability to live in extreme environments and can be used to learn how to overcome limited resources and other environmental issues.
Moon-Based Commercial Enterprises: When the early pioneers headed west and expanded our Nation, they did not carry everything with them that they would need for their journey. They “lived off the land” and we will also need to use those resources available to us along our journey, starting with the moon.
There are numerous moon-based commercial activities that could significantly offset the cost of a moon base. Just a few of these are lunar refueling or servicing stations for satellites, lunar mining and space tourism. These commercial activities would allow us to return national treasures from space and provide a significant return on our space investment.
Scientific research: The moon offers an incredible opportunity to further human understanding and discovery. Since the moon’s ancient surface is relatively undisturbed, study of its geology can help us better understand the geological history of Earth. Further, the moon’s vacuum environment can’t be duplicated on the Earth or in low-Earth orbit, and could lead to new materials, advanced alloys, medicines and innovative ways to deal with limited resources on Earth. Radio telescopes on the far side of the moon would be shielded from all radio signals (noise pollution) from Earth, allowing tremendous sensitivity increases and telescopes pointed at the Earth could identify and predict weather and climate changes.
If we return to the moon just for science and exploration then activities will be limited by the amount of money our nation is willing to devote. But, if we establish a sustainable, economically viable lunar base then our science and exploration will be limited only by our imagination.
Education: Our children are our best investment for the future, and our space program is a tremendous motivator. Our Nation has seen a steady decline in the number of students studying math and science. The space program can help turn this trend around. I can personally attest to the ability of the space program to encourage students based on the fact that I enrolled in math and science courses and began the pursuit of an engineering degree the day after the first space shuttle mission landed. The creation of a permanent lunar base will inspire millions of young people toward higher education and help maintain our Nation’s technological leadership.
Resources and Other Benefits: Since we live in a world of finite resources and the global population continues to grow, at some point the human race must utilize resources from space in order to survive. We are already constrained by our limited resources, and the decisions we make today will have a profound affect on the future of humanity.
Using resources and energy from space will enable continued growth and the spread of prosperity to the developing world without destroying our planet. Our minimal investment in space exploration (less than 1 percent of the U.S. budget) reaps tremendous intangible benefits in almost every aspect of society, from technology development to high-tech jobs. When we reach the point of sustainable space operations we will be able to transform the world from a place where nations quarrel over scarce resources to one where the basic needs of all people are met and we unite in the common adventure of exploration. The first step is a sustainable permanent human lunar settlement.
How should we go about this important undertaking? A good analogy to look at is the U.S. railroad system. The greatest obstacle for the first railroad developers was financial risk. Purchasing right of way, paying wages for large workforces and buying materials and equipment were prohibitively expensive. But the federal government stepped in, orchestrating massive land grants and other incentives. Once initial government investment was assured, enterprising developers invested enormous sums to bridge vast valleys and tunnel through enormous mountains.
Today we are faced with similar obstacles in the development and use of space for the benefit of humanity. Potential space developers face enormous up-front costs for high-risk, long-term returns on investment. To capitalize on the tremendous moon-based opportunities, our nation should establish the basic infrastructure for a transportation system between the Earth and the moon and a sustainable human settlement on the moon. Once this initial investment is made, commercial revenue-generating activities can be established. Just as our investment in the railroad, interstate road system, hydro-electric dams and other large federal projects have been paid back many times over by increased productivity and quality of life, so will our investment in lunar infrastructure.
We are poised on the doorstep of an incredible opportunity to benefit all of humanity. We have the technology and the ability to make this a reality — we need only the will to see it through. We need to choose a course toward the utilization of space to increase our available resources, global prosperity, quality of life, technological advancement, and environmental stewardship. Just as we look back and thank those before us for developing things most of us take for granted such as railroads and highways, the generations to come should be able to look back and thank us for committing to sustainable space exploration.
Britain has created a new national space agency, with plans to build a multimillion-dollar space innovation center. Until now UK space policy has been split between government departments. “The new agency will be a focal point in order to coordinate in a much more streamlined and efficient manner, working both on national projects and alongside ESA for the wider industry as well” said the UK’s first astronaut Major Tim Peake, who was selected in 2009 to represent England in space.
The U.K. Space Agency (UKSA) will begin operation – and have a new website available — by April 1, 2010.
“The action we’re taking today shows that we’re really serious about space,” said Lord Paul Drayson, U.K. Minister for Science and Innovation. “The U.K. Space Agency will give the sector the muscle it needs to fulfill its ambition.”
Drayson and Peake both said that the British space industry has remained strong despite recession troubles elsewhere and could grow into a $60 billion-a-year industry and create more than 100,000 jobs over the next 20 years.
“Our industry is really a hidden success story,” said Peake speaking on the BBC, “even during economic downturn, the space sector has been one of the few industry that has shown steady growth. We are in the forefront of the robotics technology and manufacturing small satellites and telecommunications as well.”
Peake said the UK space industry currently add $6.5 billion pounds to the economy and employs 68,000 people.
No new money will be added to the UK space budget, and the 200 million pounds allocated for UKSA is a consolidation of existing funding.
Peake said this doesn’t mean that the UK will leave the ESA alliance. “It is not a case of forging our way on our own. Every country that is in ESA also has their own agency and space policy. The ESA allows us to get involved in projects that no single country could afford to.”
In reading reactions from some of the UK bloggers, however, most convey skepticism about the new organization.
In New Scientist, Dr.Stu Clark wonders where the science is among the allocations for buildings and new technology. Plus he’s not sure if the plan for the UKSA is sustainable. “So it’s all very well having a 20-year plan, but the big question is whether UKSA can survive the next six months.”
At Astronomyblog, Stuart Lowe expressed disappointment. “For me, the launch has been a let down. We were led to believe that UKSA would be a NASA for the UK. The reality is far from it… I want to have an fantastic, inspiring, space agency. I want us to invest in it like we mean it. I want a NASA. I feel as though we’ve got a refurbished, second-hand agency that might collapse as soon as it leaves the launchpad and never make it past the General Election. Come on UK. You can do so much better.”
The e-Astronomer isn’t too fond of the UKSA logo: We got an exciting new logo. Actually I hated it. Looks like something somebody invented for a fictional fascist party in a cheap TV drama. Modern and thrusting and all that. But I guess its memorable.
Still others ask the big question: How is UKSA going to be pronounced? “Uk-sah” or “You-Kay-Ess-Ay?”
JPL has a fun article on their website detailing what future robotic exploration might entail: an armada of robots could one day fly above the mountain tops of Saturn’s moon Titan, cross its vast dunes and sail in its liquid lakes. This is the vision of Wolfgang Fink, from the California Institute of Technology. He says we are on the brink of a great paradigm shift in planetary exploration, and the next round of robotic explorers will be nothing like what we see today.
“The way we explore tomorrow will be unlike any cup of tea we’ve ever tasted,” said Fink. “We are departing from traditional approaches of a single robotic spacecraft with no redundancy that is Earth-commanded to one that allows for having multiple, expendable low-cost robots that can command themselves or other robots at various locations at the same time.”
Fink and his team members at Caltech, the U.S. Geological Survey and the University of Arizona are developing autonomous software and have built a robotic test bed that can mimic a field geologist or astronaut, capable of working independently and as part of a larger team. This software will allow a robot to think on its own, identify problems and possible hazards, determine areas of interest and prioritize targets for a close-up look.
The way things work now, engineers command a rover or spacecraft to carry out certain tasks and then wait for them to be executed. They have little or no flexibility in changing their game plan as events unfold; for example, to image a landslide or cryovolcanic eruption as it happens, or investigate a methane outgassing event.
“In the future, multiple robots will be in the driver’s seat,” Fink said. These robots would share information in almost real time. This type of exploration may one day be used on a mission to Titan, Mars and other planetary bodies. Current proposals for Titan would use an orbiter, an air balloon and rovers or lake landers.
In this mission scenario, an orbiter would circle Titan with a global view of the moon, with an air balloon or airship floating overhead to provide a birds-eye view of mountain ranges, lakes and canyons. On the ground, a rover or lake lander would explore the moon’s nooks and crannies. The orbiter would “speak” directly to the air balloon and command it to fly over a certain region for a closer look. This aerial balloon would be in contact with several small rovers on the ground and command them to move to areas identified from overhead.
“This type of exploration is referred to as tier-scalable reconnaissance,” said Fink. “It’s sort of like commanding a small army of robots operating in space, in the air and on the ground simultaneously.”
A rover might report that it’s seeing smooth rocks in the local vicinity, while the airship or orbiter could confirm that indeed the rover is in a dry riverbed – unlike current missions, which focus only on a global view from far above but can’t provide information on a local scale to tell the rover that indeed it is sitting in the middle of dry riverbed.
A current example of this type of exploration can best be seen at Mars with the communications relay between the rovers and orbiting spacecraft like the Mars Reconnaissance Orbiter. However, that information is just relayed and not shared amongst the spacecraft or used to directly control them.
“One day an entire fleet of robots will be autonomously commanded at once. This armada of robots will be our eyes, ears, arms and legs in space, in the air, and on the ground, capable of responding to their environment without us, to explore and embrace the unknown,” he added.
Have astronauts from Earth ever stepped foot on Mercury? No, Mercury has been visited by spacecraft from Earth, but no human has ever gone into orbit around Mercury, let alone stepped on the surface. Just what would it take to visit Mercury?
Humans attempting to visit Mercury would find a similar environment to the Moon. Mercury is airless, so they would need a spacesuit to protect themselves from the vacuum of space. However, the temperatures on Mercury are much greater. During the daytime, the surface of Mercury at the equator rises to 700 Kelvin (427 degrees C). Just for comparison, the surface of the Moon only rises to 390 Kelvin (117 degrees C) during the daytime. So you would need some kind of protection from the intense heat.
But then, nighttime on Mercury dips down to only 100 Kelvin (-173 degrees C) – that’s the same low temperatures you get on the Moon at night. So an astronaut’s spacesuit would need to be able to keep an astronaut warm when they’re in the shade.
The travel time to the Moon is only about 3 days. But the travel time to Mercury is much longer. That’s partly because Mercury is much further away – 10s of millions km. But spacecraft also need to take special trajectories so they can get into orbit around Mercury. All of the spacecraft that have visited Mercury have taken longer than a year to reach the planet. That would be a long, hot journey for astronauts.
Maybe some day in the future humans will visit Mercury, but it hasn’t happened yet.
Why do we explore? In the days of Magellan, Columbus and da Gama, undoubtedly the average person thought it was foolish to risk lives and spend large amounts of money to find out what was beyond the horizon. Those explorers didn’t find what they expected, but their explorations changed the world.
What drives us to explore and discover is what we don’t know, and the spirit of exploration inspires us to create and invent so that we can go explore and possibly change the world. We don’t know yet exactly what we’ll find if humans ever go to Mars, Europa or beyond, but if we stay in our caves we’ll never find out. Similarly, space probes and telescopes like Hubble, as well as ground-based telescopes have helped us explore remotely and have facilitated the discovery of so many things we didn’t know — and didn’t expect — about our universe.
However, exploration takes money.
The most often-used argument against space exploration is that we should use that money to alleviate problems here on Earth. But that argument fails to realize that NASA doesn’t just pack millions of dollar bills into a rocket and blast them into space. The money NASA uses creates jobs, providing an opportunity for some of the world’s brightest minds to use their talents to, yes, actually benefit humanity. NASA’s exploration spurs inventions that we use everyday, many which save lives and improve the quality of life. Plus, we’re expanding our horizons and feeding our curiosity, while learning so, so much and attempting to answer really big questions about ourselves and the cosmos.
NASA’s annual budget for fiscal year 2009 is $17.2 billion. The proposed budget for FY 2010 would raise it to about $18.7 billion. That sounds like a lot of money, and it is, but let’s put it in perspective. The US annual budget is almost $3 trillion and NASA’s cut of the US budget is less than 1%, which isn’t big enough to create even a single line on this pie chart. A few other things to put NASA’s budget in perspective:
Former NASA administrator Mike Griffin mentioned recently that US consumers spend more on pizza ($27 billion) than NASA’s budget. (Head nod to Ian O’Neill)
Miles O’Brien recently brought it to our attention that the amount of money Bernie Maddof scammed with his Ponzi scheme ($50 billion) is way bigger than NASA’s budget.
Americans spend a lot of money on some pretty ridiculous things. Returning to that oft-used phrase about spending the money used in space to solve the problems on Earth, consider this: *
Annually, Americans spend about $88.8 billion on tobacco products and another $97 billion on alcohol. $313 billion is spent each year in America for treatment of tobacco and alcohol related medical problems.
Likewise, people in the US spend about $64 billion on illegal drugs, and $114.2 billion for health-related care of drug use.
Americans also spend $586.5 billion a year on gambling.
It’s possible we could give up some other things to help alleviate the problems in our country without having to give up the spirit of exploration.
*the numbers used here are from various years, depending on what was readily available, but range from the years 2000 and 2008.
If you’re looking to build a powerful spaceship, nothing’s better than antimatter. It’s lightweight, extremely powerful and could generate tremendous velocity. However, it’s enormously expensive to create, volatile, and releases torrents of destructive gamma rays. NASA’s Institute for Advanced Concepts is funding a team of researchers to try and design an antimatter-powered spacecraft that could avoid some of those problems.
Most self-respecting starships in science fiction stories use anti matter as fuel for a good reason – it’s the most potent fuel known. While tons of chemical fuel are needed to propel a human mission to Mars, just tens of milligrams of antimatter will do (a milligram is about one-thousandth the weight of a piece of the original M&M candy).
However, in reality this power comes with a price. Some antimatter reactions produce blasts of high energy gamma rays. Gamma rays are like X-rays on steroids. They penetrate matter and break apart molecules in cells, so they are not healthy to be around. High-energy gamma rays can also make the engines radioactive by fragmenting atoms of the engine material.
The NASA Institute for Advanced Concepts (NIAC) is funding a team of researchers working on a new design for an antimatter-powered spaceship that avoids this nasty side effect by producing gamma rays with much lower energy.
Antimatter is sometimes called the mirror image of normal matter because while it looks just like ordinary matter, some properties are reversed. For example, normal electrons, the familiar particles that carry electric current in everything from cell phones to plasma TVs, have a negative electric charge. Anti-electrons have a positive charge, so scientists dubbed them “positrons”.
When antimatter meets matter, both annihilate in a flash of energy. This complete conversion to energy is what makes antimatter so powerful. Even the nuclear reactions that power atomic bombs come in a distant second, with only about three percent of their mass converted to energy.
Previous antimatter-powered spaceship designs employed antiprotons, which produce high-energy gamma rays when they annihilate. The new design will use positrons, which make gamma rays with about 400 times less energy.
The NIAC research is a preliminary study to see if the idea is feasible. If it looks promising, and funds are available to successfully develop the technology, a positron-powered spaceship would have a couple advantages over the existing plans for a human mission to Mars, called the Mars Reference Mission.
“The most significant advantage is more safety,” said Dr. Gerald Smith of Positronics Research, LLC, in Santa Fe, New Mexico. The current Reference Mission calls for a nuclear reactor to propel the spaceship to Mars. This is desirable because nuclear propulsion reduces travel time to Mars, increasing safety for the crew by reducing their exposure to cosmic rays. Also, a chemically-powered spacecraft weighs much more and costs a lot more to launch. The reactor also provides ample power for the three-year mission. But nuclear reactors are complex, so more things could potentially go wrong during the mission. “However, the positron reactor offers the same advantages but is relatively simple,” said Smith, lead researcher for the NIAC study.
Also, nuclear reactors are radioactive even after their fuel is used up. After the ship arrives at Mars, Reference Mission plans are to direct the reactor into an orbit that will not encounter Earth for at least a million years, when the residual radiation will be reduced to safe levels. However, there is no leftover radiation in a positron reactor after the fuel is used up, so there is no safety concern if the spent positron reactor should accidentally re-enter Earth’s atmosphere, according to the team.
It will be safer to launch as well. If a rocket carrying a nuclear reactor explodes, it could release radioactive particles into the atmosphere. “Our positron spacecraft would release a flash of gamma-rays if it exploded, but the gamma rays would be gone in an instant. There would be no radioactive particles to drift on the wind. The flash would also be confined to a relatively small area. The danger zone would be about a kilometer (about a half-mile) around the spacecraft. An ordinary large chemically-powered rocket has a danger zone of about the same size, due to the big fireball that would result from its explosion,” said Smith.
Another significant advantage is speed. The Reference Mission spacecraft would take astronauts to Mars in about 180 days. “Our advanced designs, like the gas core and the ablative engine concepts, could take astronauts to Mars in half that time, and perhaps even in as little as 45 days,” said Kirby Meyer, an engineer with Positronics Research on the study.
Advanced engines do this by running hot, which increases their efficiency or “specific impulse” (Isp). Isp is the “miles per gallon” of rocketry: the higher the Isp, the faster you can go before you use up your fuel supply. The best chemical rockets, like NASA’s Space Shuttle main engine, max out at around 450 seconds, which means a pound of fuel will produce a pound of thrust for 450 seconds. A nuclear or positron reactor can make over 900 seconds. The ablative engine, which slowly vaporizes itself to produce thrust, could go as high as 5,000 seconds.
One technical challenge to making a positron spacecraft a reality is the cost to produce the positrons. Because of its spectacular effect on normal matter, there is not a lot of antimatter sitting around. In space, it is created in collisions of high-speed particles called cosmic rays. On Earth, it has to be created in particle accelerators, immense machines that smash atoms together. The machines are normally used to discover how the universe works on a deep, fundamental level, but they can be harnessed as antimatter factories.
“A rough estimate to produce the 10 milligrams of positrons needed for a human Mars mission is about 250 million dollars using technology that is currently under development,” said Smith. This cost might seem high, but it has to be considered against the extra cost to launch a heavier chemical rocket (current launch costs are about $10,000 per pound) or the cost to fuel and make safe a nuclear reactor. “Based on the experience with nuclear technology, it seems reasonable to expect positron production cost to go down with more research,” added Smith.
Another challenge is storing enough positrons in a small space. Because they annihilate normal matter, you can’t just stuff them in a bottle. Instead, they have to be contained with electric and magnetic fields. “We feel confident that with a dedicated research and development program, these challenges can be overcome,” said Smith.
If this is so, perhaps the first humans to reach Mars will arrive in spaceships powered by the same source that fired starships across the universes of our science fiction dreams.