Why do we engage in space exploration?

26 August 20155 March 2016 / raminskibba / 2 Comments

A review of diverse perspectives on space exploration and extraterrestrial life reveal fundamentally human hopes, fears and flaws

Since the dawn of civilization thousands of years ago, humans have looked to the skies. Archaeologists have found evidence of people from China, India, and Persia to Europe and Mesoamerica observing and contemplating the many stars and planets that fascinated them. We humans have also wondered about—and often hoped for—the existence of other intelligent life out there. Considering the large number of planets in the Milky Way and in billions of other galaxies, perhaps we are not alone, and maybe even while you are reading this, extraterrestrials could be looking in our direction through their telescopes or sending us interstellar telegrams. But if our galaxy teems with aliens, following Italian physicist Enrico Fermi’s persistent question, we must ask, “Where are they?”

Artist’s depiction of a travel poster for a “Tatooine-like” planet orbiting two suns, recently discovered by NASA’s Kepler spacecraft. (Courtesy: NASA)

Two recent pieces in the New Yorker and New York Times, as well as numerous books over the past couple years, motivate me to consider this and related questions too. Astronomers and astrophysicists around the world, including scientists working with NASA, the European Space Agency (ESA), the Japanese Space Agency (JAXA) and many others, have many varieties of telescopes and observatories on Earth and in space, just because we want to investigate and learn about our galactic neighborhood and beyond. We also attempt to communicate, like sending a message in a bottle, with the Golden Records aboard the Voyager spacecrafts, and we listen for alien attempts to contact us. In our lifetime, we have dreams of sending humans to Mars and to more distant planets. Why do we do this? We do it for many reasons, but especially because humans are explorers: we’re driven to see what’s out there and to “boldly go where no one has gone before.” As Carl Sagan put it in Cosmos, “Exploration is in our nature. We began as wanderers, and we are wanderers still.”

Views of human space exploration

Elizabeth Kolbert reviews three recently published and forthcoming books by Chris Impey, an astronomer at the University of Arizona (where I used to work three years ago), Stephen Petranek, a journalist at Discover, and Erik Conway, a historian of science at Jet Propulsion Laboratory. (She did not mention an award-winning book by Lee Billings, Five Billion Years of Solitude, which I will review in a later post.) She fault finds with the overoptimistic and possibly naïve “boosterism” of Impey and Petranek. “The notion that we could…hurl [humans]…into space, and that this would, to use Petranek’s formulation, constitute ‘our best hope,’ is either fantastically far-fetched or deeply depressing.” She asks, “Why is it that the same people who believe we can live off-Earth tend to believe we can’t live on it?”

Kolbert’s assessment has some merit. Astrophiles and space enthusiasts, of which I am one, sometimes seem to neglect Earth (and Earthlings) in all its wonder, marvels, complexity, brutality and messiness. But is the primary reason for exploring the universe that we can’t take care of ourselves on Earth? Mars should not be viewed as a backup plan but rather as one of many important steps toward better understanding our little corner of the galaxy. Furthermore, we should be clear that sending humans to Mars and more distant worlds is an incredibly complicated and dangerous prospect, with no guarantee of success. Even if the long distances could be traversed—at its closest, Mars comes by at least a staggering 50 million miles (80 million km) away, and then the nearest star, Alpha Centauri, is about 25 trillion miles from us—future human outposts would face many obstacles. The popular novel by Andy Weir, The Martian, demonstrates only some of the extraordinary challenges of living beyond our home planet.

Overview of components of NASA’s Journey to Mars program, which seeks to send humans to the red planet in the 2030s. (Credit: NASA)

Though Kolbert criticizes Conway’s dry writing style, she clearly sympathizes with his views. “If people ever do get to the red planet—an event that Conway…considers ‘unlikely’ in his lifetime—they’ll immediately wreck the place just by showing up…If people start rejiggering the atmosphere and thawing the [planet’s soil], so much the worse.” This line of criticism refers to flaws of geoengineering and of the human species itself. Many times in history, humans ventured out acting like explorers, and then became colonists and then colonialists, exploiting every region’s environment and inhabitants.

Note that Kolbert is a journalist with considerable experience writing about climate, ecology and biology, while astrophysics and space sciences require a stretch of her expertise. In her excellent Pulitzer Prize-winning book, The Sixth Extinction, Kolbert argues provocatively that humans could be viewed as invasive species transforming the planet faster than other species can adapt, thereby constituting a danger to them. “As soon as humans started using [language], they pushed beyond the limits of [the] world.” I agree that humans must radically improve their relationship with nature and Earth itself, but this does not preclude space travel; on the contrary, the goal of exploring other worlds should be one aspect of our longer-term and larger-scale perspective of humanity’s place in the universe.

Views of extraterrestrial intelligence

Dennis Overbye, a science writer specializing in physics and astronomy, covers similar ground, but focuses more on the search for extraterrestrial intelligence (SETI). He mentions the Drake Equation, named after the American astronomer Frank Drake, which quantifies our understanding of the likelihood of intelligent life on other planets with whom we might communicate. Both Drake and Sagan “stressed that a key unknown element in their equations was the average lifetime of technological civilizations.” If advanced species don’t survive very long, then the possibility of contact between overlapping civilizations becomes highly improbable. It would be unfortunate if similarly advanced civilizations, like Earthlings and Klingons, could never meet.

Overbye introduces the controversial University of Oxford philosopher, Nick Bostrom, who is rooting for us to fail in our search for ETs! “It would be good news if we find Mars to be sterile. Dead rocks and lifeless sands would lift my spirit.”

Bostrom bases his argument on a concept he refers to as the Great Filter. Considering the likelihood of advanced civilizations, many conditions and criteria must be satisfied and steps must be taken before a planet in the “habitable zone” has a chance of harboring intelligent life. The planet probably must have the right kind of atmosphere and a significant amount of liquid water and some kind of possibly carbon-based building blocks of life, and after that, the alien species’ evolutionary developments could go in any direction, not necessarily in a direction that facilitates intelligence. In addition, asteroids, pandemics, or volcanic eruptions could wipe out this alien life before it got anywhere. In other words, myriad perils and difficulties filter out the planets, such that only a few might have species that survive and reach a level of social and technological advancement comparable to those of humans.

On the other hand, if we do find life on other planets and if intelligent extraterrestrial life is relatively ubiquitous, our lack of contact with them could mean that advanced civilizations have a short lifetime. Perhaps the Great Filter is ahead of us, “since there is no reason to think that we will be any luckier than other species.” Maybe nuclear war, climate change, or killer robots might wipe us out before we have the chance to explore the galaxy.

I am not convinced by Bostrom’s pessimism. Even if the Great Filter is ahead of us, implying that humans face more existential threats in the future than have been overcome in the past, this doesn’t mean that we are doomed. Humanity does have major problems with acknowledging large-scale impacts and long-term outlooks, but I hope we could learn to change before it is too late.

A more positive outlook

We have learned a lot about planets, stars, galaxies, black holes and the distant universe from our tiny vantage point. But we would be immodest and mistaken to brazenly presume that we’ve already figured out the rest of the universe. We really don’t know how many other “intelligent” species might be out there, and if so, how far they are, what level of evolution they’re at (if evolution is a linear process), or whether or how they might communicate with us. We should continue to discuss and examine these questions though.

While traveling to other planets will take a long time, in the meantime astronomers continue to make exciting discoveries of possibly “Earth-like” planets, such as Kepler-452b, an older bigger cousin to our world. It seems likely that the Earth has a very big family, with many cousins in the Milky Way alone.

So why do we engage in space exploration and why do we seek out extraterrestrial life? This question seems to transform into questions about who we are and how we view our role in the universe. I believe that humans are fundamentally explorers, not only in a scientific sense, and we have boundless curiosity and wonder about our planet and the universe we live in. Humans also explore the depths of the oceans and dense rainforests and they scour remote regions in arid deserts and frigid glaciers (while they still remain), just to see what they’re like and to look for and observe different lifeforms.

More importantly, even after tens of thousands of years of human existence, we are still exploring who we are, not just with scientific work by psychologists and sociologists but also with novelists, poets and philosophers. We still have much to learn. To quote from Q, a capricious yet occasionally wise Star Trek character, “That is the exploration that awaits you: not mapping stars and studying nebulae, but charting the unknown possibilities of existence!”

A Bad Week for Commercial Spaceflight

8 November 20146 March 2015 / raminskibba / Leave a comment

The US commercial space industry did not fare well last week. Two accidents on 28th and 31st October highlight the risks, costs, and difficulties of spaceflight—as well as pointing to potential setbacks for commercial spaceflight. (If you’re interested, other news outlets have commented on these issues as well, such as here and here and here.) Pardon the self-promotion, but you can check out our discussion with Ken Kremer on a Weekly Space Hangout with Universe Today on the 31st for more information.

Orbital Sciences’ Antares rocket

First, on Tuesday (the 28th), an unmanned 13-story rocket designed by Orbital Sciences Corp. exploded a few seconds after liftoff off the coast of Virginia at NASA’s Wallops Flight Facility. It carried a Cygnus capsule with more than 5,000 pounds (2,300 kg) of hundreds of millions of dollars of supplies and equipment, as well as school students’ science experiments. It was bound for the International Space Station (ISS) and was the first time a resupply mission contracted by NASA to a private company failed. Fortunately, no one was hurt. Though the flight facility is designed to handle explosion and fire, there was significant damage to the launch infrastructure.

Journalists were pretty close to the launch zone, and this video (tweeted by Pamela Gay) shows the launch, explosion, and fleeing from the potentially dangerous area (see also videos at LA Times):

It will take time to recover from this. And we will have to see how much this damages Orbital Science Corp.’s reputation and NASA’s efforts to outsource orbital flights. Four previous Antares flights, including three to the station, had launched successfully, and five resupply flights remain in the company’s multi-billion dollar contract, the next one being scheduled for April. This likely will be delayed though, and according to Orbital’s press release, they will implement a propulsion system upgrade previously planned for 2016. The loss of this supply vessel doesn’t pose an immediate problem for the ISS’s crew, which includes two from NASA, one from the European Space Agency (ESA), and three Russians. The second US supply line to the ISS is with Space Exploration Technologies (SpaceX), which has its next launch planned for 9th December. Although the ISS crew and their missions are not in any danger, this loss significantly affects Orbital Sciences, and more work and investment will be needed to proceed.

NASA held a press conference the same day as the accident, and their investigation into the cause(s) of the explosion and failed launch continues. These space-bound rockets have many components—many things that could go wrong—and there is considerable debris to examine, so it could take awhile. It’s not clear whether extra weight and length were factors in the accident, for example. A turbopump-related failure in one of the two Aerojet Rocketdyne AJ26 stage-one engines might have been the culprit. These liquid oxygen and kerosene fueled engines, produced during the Soviet era in Russia (with modifications), likely will be discontinued in future Antares rockets.

Virgin Galactic’s SpaceShipTwo

And now for Act Two. Virgin Galactic’s SpaceShipTwo, part of a commercial space program founded by Richard Branson, suffered an “in-flight anomaly” on Halloween. It crashed midflight during testing and broke into several pieces over the Mojave Desert (north of Los Angeles, for you non-Californians). One pilot (Michael Alsbury) was killed and was unfortunately still strapped to his seat in the wreckage. The other pilot (Peter Siebold) successfully ejected at an altitude of around 50,000 feet and deployed his parachute. He was airlifted to a hospital and treated for injuries.

After successful programs like Mercury, Gemini, and Apollo, NASA has been attempting to privatize spaceflight and redefine its missions partly because of tighter budgets over the past couple decades. According to the NY Times and Lori Garver (former deputy administrator at NASA), public funds should be focused on activities that advance technology and provide public benefits to all, like planetary science. At the same time, Garver said, the government should encourage private companies to move ahead and find innovative ways of reducing costs.

The National Transportation Safety Board (NTSB) held a press conference last Sunday with more details. A new fuel was being tested on this flight, which may or may not have been an issue, and a “feathering mechanism” might have been deployed prematurely on the spacecraft, when it was traveling beyond the speed of sound. But the investigation is still in progress, and I’ll give you more details in the near future. In any case, our thoughts are with the pilots and their families.

So what does the future hold? I’m not sure, but it looks like Orbital Sciences (and SpaceX) and Virgin Galactic will continue their spaceflight programs, as they should. Both of these accidents are unfortunate and costly—to say the least—but they should not deter us from space exploration. We have much to gain from continuing these programs. At the same time, I think we should be careful about outsourcing too much; I believe that our best prospects lie with continuing to invest funding, resources, and personnel in NASA, ESA, and other space agencies, where our scientific expertise and oversight are the greatest, and where short-term setbacks are less likely to affect our long-term objectives or derail whole exploration programs.

Nuclear (non)proliferation and the Security of Earth

28 August 201425 February 2015 / raminskibba / Leave a comment

We all want global security, since at least for now, the Earth is the only planet we’ve got. In the words of The Tick (in the 1990s cartoon), “You can’t blow up the world…That’s where I keep all my stuff!”

In my previous post, I ended by raising the issue of the political scientist James Doyle, who was apparently fired from the Department of Energy’s (DOE’s) Los Alamos National Laboratory (LANL) in New Mexico after publishing a scholarly article questioning US nuclear weapons doctrine and defending President Obama’s goal of a nuclear weapons-free future. James Doyle’s article was titled “Why Eliminate Nuclear Weapons?,” and I’ll give you an extended quote from its conclusions, as it’s written rather well:

The marginal contribution that nuclear deterrence now makes to the absence of major aggression between great powers is being purchased at too high a price. That price is the constant risk that a complex, tightly coupled and largely automated system subject to normal, systemic and human error will, as science tells us, inevitably fail, and fail catastrophically, with unprecedented and unjustified loss of civilian life…Nuclear weapons are useless for confronting and resolving the most likely future international security challenges, but steady progress towards the elimination of such weapons can help nations confront these transnational problems…[E]limination of nuclear weapons will allow creative, intellectual, technical and financial resources now devoted to nuclear threats to be focused toward the resolution of transnational crises faced by all nations. As nuclear weapons are drawn down those resources can be re-focused toward developing clean energy, carbon-capture technologies, clean water management and low-impact, high-productivity agriculture.

The Federation of American Scientists (FAS) is calling on Energy Secretary Ernest Moniz to get involved in the case. According to Science journal, the lab recently made the following statement: “James Doyle’s separation from Los Alamos National Laboratory was a layoff due to the lack of available or anticipated funding in his area of expertise. The separation was unrelated to his publications or professional writings.” Many external arms control specialists are skeptical and believe Doyle’s downfall is the result of his airing of views that are unpopular among those opposing disarmament, including some of the Armed Services Committee’s Republican leaders and staff. And if you’re curious about how many resources LANL spends on weapons activity versus nonproliferation, take a look at the following graph (reported by the Center for Public Integrity).

Although nuclear weapons (and “mutually assured destruction”) seem like a Cold War issue and a thing of the past, they’re as relevant as ever today. In and near the Middle East, where Israel, Pakistan, and India have nuclear weapons, proliferation is a real concern. In addition, according to Newsweek, countries in Russia’s neighborhood are now considering nuclear deterrence. Altogether, the US possesses 2,104 (active) nuclear warheads, Russia has a similar number, and numerous other countries have hundreds either mounted on planes or on submarines. Germany will not continue its nuclear-hosting duties beyond the 2020s, and a Central European official was recently quoted as saying, “If the Germans don’t want [the bombs], we’ll take them.”

According to Scientific American, the FAS begin with the “scientists’ movement” in the mid-1940s when many scientists who had worked on the Manhattan Project recognized that they had a special responsibility to educate policymakers and the public about the implications of nuclear energy and nuclear weapons. (Carl Sagan, who is one of my heroes, had served on FAS’s advisory council and was a leading scientist devoted to reversing the nuclear arms race.) The FAS’s Nuclear Weapons Database is one of the most reliable sources on global nuclear arsenals, and the numbers in the previous paragraph were obtained from it. As far as we know, the US is not developing new nuclear weapons, but unfortunately it’s improving the weapon delivery systems (see this report from the Union of Concerned Scientists). This does not aid the goals of nonproliferation and reducing nuclear weapons, nor does the US’s nearly 500 land-based missiles on “hair-trigger” alert.

As I’ve mentioned in a previous post, nuclear weapons are also relevant to space security and to the risk of a space arms race. Although deploying nuclear weapons in space may be prohibitively expensive and are a violation of the Outer Space Treaty, certain nuclear missiles could have trajectories outside of the Earth’s atmosphere, and anti-satellite missiles are another concern. In any case, space weapons—nuclear or otherwise—increase tensions between countries and increase the risk of conflict.

Another related issue is the Nuclear Nonproliferation Treaty (which, by the way, has never been signed by India, Israel, and Pakistan). In the 21st century era of worsening climate change, we need alternatives to fossil fuel-based energy, but nuclear energy surely is not ideal. It’s not clear how much, if it all, nuclear energy should play a role in our transition to a fossil fuel-free economy. Even in Iran, where there is an apparent abundance of oil, people are trying to prepare for the transition, and as in other places, they have turned to nuclear energy. An additional concern is that developing nuclear energy technologies produces a pathway for countries to develop nuclear weaponry as well; unfortunately, we’ve seen other countries follow this path already. In the case of Iran, as usual, what is required is a diplomatic and political settlement. As argued in a report by the FAS and the Carnegie Endowment for International Peace, by offering Iran cutting-edge alternative energy technologies, especially to take advantage of the country’s solar energy potential, a positive precedent could be set for other nuclear-hopefuls.

Extreme Space Weather Event #23072012

29 July 201413 January 2015 / raminskibba / 1 Comment

You may have seen some dramatic headlines in the news last week: “‘Extreme solar storm’ could have pulled the plug on Earth” (Guardian); “Solar ‘superstorm’ just missed Earth in 2012” (CBS); “How a solar storm two years ago nearly caused a catastrophe on Earth” (Washington Post blog). Also see this Physics Today article, which was published online today and reviewed the press attention to the event.

Though journalists and editors often write hyperbolic headlines, the danger from solar storms is very real, though extreme ones are as rare as massive earthquakes. When you think of solar flares and eruptions threatening humans, it may evoke Stanislaw Lem’s Solaris or the Doctor Who episode 42, but at least our sun isn’t sentient (as far as we know)!

The solar storm in question occurred two years ago on 23 July 2012, and the media reported on it following a NASA public-information release and accompanying four-minute YouTube video (see below). It seems that those of us who live on Earth and use electronic technology were lucky that this was a near miss. The threat of solar storms is also relevant to “space security”, which I wrote about in a previous post.

The paper itself was published last fall in the Space Weather journal by Daniel Baker, of the Laboratory for Atmospheric and Space Physics at the University of Colorado, and six colleagues from NASA, Catholic University, and the University of New Hampshire. Its full title is “A major solar eruptive event in July 2012: Defining extreme space weather scenarios,” and here is their abstract (abridged):

A key goal for space weather studies is to define severe and extreme conditions that might plausibly afflict human technology. On 23 July 2012, solar active region 1520 (141°W heliographic longitude) gave rise to a powerful coronal mass ejection (CME) with an initial speed that was determined to be 2500 ± 500 km/s [5.6 million miles/hr!]… In this paper, we address the question of what would have happened if this powerful interplanetary event had been Earthward directed. Using a well-proven geomagnetic storm forecast model, we find that the 23–24 July event would certainly have produced a geomagnetic storm that was comparable to the largest events of the twentieth century…This finding has far reaching implications because it demonstrates that extreme space weather conditions such as those during March of 1989 or September of 1859 can happen even during a modest solar activity cycle such as the one presently underway. We argue that this extreme event should immediately be employed by the space weather community to model severe space weather effects on technological systems such as the electric power grid.

The solar storm missed the Earth but hit NASA’s STEREO-A spacecraft, which was safely outside the Earth’s magnetosphere and was able to measure and observe the approaching CME, a billion-ton cloud of magnetized plasma. “I have come away from our recent studies more convinced than ever that Earth and its inhabitants were incredibly fortunate that the 2012 eruption happened when it did,” says Baker. “If the eruption had occurred only one week earlier, Earth would have been in the line of fire.” According to the simulations in their follow-up paper by Chigomezyo Ngwira et al., had the 2012 CME hit the Earth, it could have produced comparable or larger geomagnetically induced electric fields to those produced by previously observed Earth-directed events and would have put electrical power grids, global navigation systems, orbiting satellites, etc. at risk.

Pete Riley, a physicist at Predictive Science Inc., published a paper in 2012 in the same journal entitled “On the probability of occurrence of extreme space weather events.” He analyzed historical records of solar storms, and by extrapolating the frequency of ordinary storms, he calculated the odds that a Carrington-class storm (which occurred in 1859) would hit Earth in the next ten years is between 8.5 and 12%!

NASA has calculated that the cost of the 2012 CME hitting the Earth would have been twenty times the devastation caused by hurricane Katrina—on the order of $2tn. The storm would have begun with a solar flare, which itself can cause radio blackouts and GPS navigation failures, and then it would have been followed by the CME a few minutes later, potentially causing widespread havoc with global technological infrastructure. Anything that uses electricity, including water supplies, hospital equipment, and radio and television broadcasts could be shut down. How do we prepare as a society for an event like that?

An introduction to “space security”

7 March 201426 August 2014 / raminskibba / 3 Comments

I’m curious about what people refer to as “space security”, as well as space policy and sustainability, and if you’re interested, you can learn with me. This post will just be an introduction to some of the issues involved. Note that I’m not an expert on many of these issues, so take my comments and thoughts with a grain of salt.

The idea of “space security” might conjure images of invading aliens, but as much fun as that is, that’s not what I’m talking about. I’m also not planning on talking about killer asteroids and dangerous radiation, though these are much less far-fetched. For example, the Pan-STARRS survey (of which I was briefly a member a few years ago) received funding from NASA to assess the threat to the planet from Near Earth Objects, some of which pass closer to us than the moon. (A limitation of Pan-STARRS, however, was that images that happened to contain passing satellites had software applied to black out or blur the pixels in the region.) On the other hand, solar flares can produce “coronal mass ejections” and intense cosmic rays that could be hazardous to spacecraft but on Earth we’re somewhat protected by our atmosphere and magnetosphere. This and other forms of “space weather” could be the subject of another post later.

I’d like to talk about the issue of satellites, as well as weapons and reactors, in space. More than 5,000 satellites have been launched into orbit and about 1,000 are in operation today. The act of destroying a satellite or of colliding satellites can damage the space environment by creating dangerous amounts of debris. (If you’ve seen the Oscar-winning Gravity, then you know that debris from satellites can be a serious problem.) For example, in a demonstration of an anti-satellite weapon in 2007, China destroyed one of its own satellites; the resulting “space junk” then struck and destroyed a small Russian satellite last year. The following computer-generated images of the growing number of objects in low-earth orbit (courtesy of the NASA Orbital Debris Office) illustrates the problem. Only 5% of the objects are satellites; the rest are debris. Currently more than 21,000 pieces of debris larger than 10cm are being tracked, and there are as many as 500,000 additional untracted pieces larger than 1cm.

In addition, the loss of an important satellite could create or escalate a conflict, especially during a time of tension between states. The US and other countries possess “anti-satellite” weapons (ASATs) and have or are considering space-based missile defense systems. Attacks on satellites are a very real possibility, and it is important to beware of the destabilizing effects and potential for proliferation with such weapons. Moreover, since the Cold War, the US and other governments have considered deploying nuclear reactors on spacecraft, which have proven to be controversial (such as the dubiously named Project Prometheus, which was cancelled in 2006); an intentionally or unintentionally damaged nuclear reactor in space could have major consequences.

Considering that we are increasingly dependent on satellites and that there are military, commercial, and civil interests in space, how can we attempt to ensure space security and sustainability in the future? In the US, the Obama administration has a National Space Policy, which was released in June 2010. The policy mainly consists of: (1) limit further pollution of the space environment; (2) limit objects from colliding with each other and/or exploding; (3) actively removing high-risk space debris. The policy a good start, but much more could be done. An emphasis on international cooperation rather than unilateral action would help; space debris are clearly a global problem requiring global solutions. It is also important to negotiate on the control of space weapons. The US and other space powers should declare that they will not intentionally damage or disable satellites operating in accordance with the Outer Space Treaty and that they will not be the first to station weapons in space. Moreover, “space situational awareness” (SSA), which allows for the coordination of space traffic, can be improved in collaboration with other countries, and satellites can be made less vulnerable to collision or attack. Finally, the US should play an active role in negotiations with the international community on space security and sustainability. The United Nations has the Committee on the Peaceful Uses of Outer Space (COPUOS), with 76 member states, has been working on a variety of programs to improve the long-term sustainability of space activities, and in particular, to develop and adopt international standards to minimize space debris.