Why do we engage in space exploration?

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)

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)

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!”

NASA Missions Exploring Dwarf Planets Ceres and Pluto

Now I’m not a planetary astronomer, but like you, I’m excited by any kind of space exploration, and this year the NASA missions, Dawn and New Horizons, will give us the closest and most detailed views of dwarf planets yet.

What is a “dwarf planet,” you ask? Excellent question. Until about ten years ago, astronomers usually referred to small planet-like objects that were not satellites (moons) as “planetoids.” In some ways, they resembled the eight more massive planets in our solar system as well as Pluto, which had a borderline status. Astronomers discovered Charon, Eris (previously called 2003 UB313), and Ceres, and they expected to discover many more, likely rapidly expanding the ranks of our esteemed class of planets. Either they all had to be included, or a clear classification system would have to be determined and Pluto would be reclassified.

Courtesy: IAU

Courtesy: IAU

At the International Astronomical Union (IAU) meeting in Prague in 2006, astronomers opted for the latter in Resolution 5. They demoted poor Pluto, but I think they did the right thing. (I was working in Heidelberg, Germany at the time, and if I’d known how historic this IAU meeting would be, maybe I would’ve tried to attend!) The IAU’s defines a dwarf planet as “a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.” The criterion (c) is the important one here, because it means that the object has not become gravitationally dominant in its orbital zone, which is the case for Pluto and the other planetoids beyond Neptune and for Ceres, the only dwarf planet in the asteroid belt between Mars and Jupiter. These are contentious issues, and the debate even made it into the New Yorker. But let’s be clear: these things are small, and they’re all less massive than Earth’s moon.

We don’t know as much about dwarf planets as we do about the planets in our system, so let’s go exploring! What do these new space missions have in store for us?

Ceres

In 2007, NASA launched the Dawn spacecraft to study Ceres up close. A couple days ago, two centuries after Sicilian astronomer Father Giuseppe Piazzi discovered Ceres, Dawn became the first spacecraft to orbit a dwarf planet. As the deputy Principal Investigator Carol Raymond put it on Friday, this is an “historic day for planetary exploration.” Jim Green, NASA’s Planetary Science Division Director, says that with Dawn, we are “learning about building blocks of terrestrial planets in our solar system.”

Dawn has obtained excellent detailed images already, as you can see in the (sped up) animation below.

Credit:  NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Credit:
NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The pair of bright spots in a crater stand out, and astronomers are trying to figure out what they are. They might be an indication of geological activity on it’s changing surface. Ceres has a rocky core and an ice layer, and it’s also possible that these are reflective patches of ice that have been exposed by space rocks falling in and striking the surface. For more information, check out this blog post by Emily Lakdawalla and these articles in the LA Times and Wired.

As Dawn uses its propulsion systems to reshape its orbit and get closer views, astronomers expect to learn more about those spots, look for plumes, and examine the surface for strange craters or other distinguishing features. The spacecraft will later turn on its spectrometers and determine which minerals are present and how abundant they are.

Pluto

NASA launched New Horizons in 2006, and it had much farther to travel to reach Pluto. In January, NASA announced that New Horizons is making its approach to the erstwhile planet, though it’s still about 200 million kilometers away. Mark your calendars: it will fly by Pluto (as it will be traveling too fast to orbit) on 14th July, and at a distance of only 13,000 km, New Horizons’ instruments will obtain the best images yet of it. For more information, check out this article by Jason Major in Universe Today and Phil Plait in Slate.

Distant image of Pluto by New Horizons. Credit: NASA/Johns Hopkins APL/Southwest Research Institute.

Distant image of Pluto by New Horizons. Credit: NASA/Johns Hopkins APL/Southwest Research Institute.

A couple ago, leaders in planetary astronomy highlighted the importance of Dawn and New Horizons in their Decadal Survey. I think both space missions will turn out to be worthwhile, and let’s stay tuned to see what they discover over the next few months.

Science Policy at the American Astronomical Society: NASA, National Science Foundation, New Telescopes

Following my previous post, here I’ll write about some science policy-related talks, events, and news at the American Astronomical Society meeting two weeks ago.

National Aeronautics and Space Administration (NASA)

As we saw in President Obama’s State of the Union address on Tuesday, NASA’s sending Scott Kelly to join Mikhail Kornienko for a 1-year mission at the International Space Station, where they and their crewmates will carry out numerous research experiments and work on technology development. This could help toward sending manned missions to Mars in the future, which would involve much longer periods in space. Of course, actually getting to Mars involves many other challenges too; and let’s remember that the ISS has an orbit height of about 431 km while the closest distance between Earth and Mars is 54.6 million km–about 100,000 times further away. Reaching Mars is clearly an ambitious goal, but it’s achievable in the long term. (For SOTU coverage, check out these articles in Science and Universe Today.) The new budget extends the life of the ISS until at least 2024, “which is essential to achieving the goals of sending humans to deep space destinations and returning benefits to humanity through research and technology development.” The ISS accounts for most of NASA’s space operations budget, but that only accounts for a few percent of NASA’s total budget, which includes many other activities and missions.

The NASA Town Hall began with with an update on its budget for 2015, and if you’re interested in the details, take a look at my previous post. One important change is that education will not take up 1% of every project as before; instead, the new budget requires that educational activities be centralized in the Science Mission Directorate (SMD).

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The National Academies, which include the National Academy of Sciences, organize a massive effort every decade for leaders in the astronomy and astrophysics community to prioritize their goals and challenges and to make recommendations about what kinds of large-, medium-, and small-scale projects should have funding and resources invested in them. The Decadal Survey for 2010-2020, “New Worlds, New Horizons in Astronomy and Astrophysics”, is detailed and well-organized, and you can view it online. It’s complementary to the European Space Agency’s (ESA) “Cosmic Visions” programme for 2015-2025. Astronomers have produced these surveys since the 1970s, and other fields are catching on too; for example, the 2015-2025 decadal survey of ocean sciences just came out today.

The NASA spokesperson pointed out that previous Decadal Survey missions—Hubble, Chandra, and Spitzer—have now become household names, and the James Webb Space Telescope and Wide Field Infrared Survey Telescope will too. JWST will be great for astronomy and for outreach, but it is nonetheless extremely expensive and over budget, which implies that some smaller projects won’t be funded. According to this detailed article by Lee Billings, JWST is taking an ever-increasing fraction of NASA’s astrophysics budget, and based on the presentation at the town hall, it looks like that will continue for the next few years. In the meantime, WFIRST’s budget will start ramping up soon too.

In other news, at the AAS meeting we also heard updates about research grants in 2014 through NASA’s funding of Research Opportunities in Space and Earth Sciences (ROSES) funding. The Astrophysics Data Analysis Program (ADAP) was funded at $7.5M last year with a 21% proposal success rate, and the Astrophysics Theory Program (ATP) was funded at $3.5M with a 11% success rate. I didn’t catch the stats for the other programs, such as those involving exoplanet research and instrumentation. Grant funding levels have been pretty flat for the past four fiscal years, but because of the increasing number proposals, the selection rate keeps decreasing. Theoretical astrophysicists will be dismayed that no ATP proposals will be solicited in 2015, but they say that there has been no reduction in funding, just a delay.

cost-big

There were also interesting sessions about education and public outreach (E/PO) and Program Analysis Groups (PAGs) too, and I suggest checking out those links if you want more information and resources.

National Science Foundation (NSF)

I also attended the NSF town hall, and similar to the NASA one, was primarily about budget issues. The NSF budget fared alright for fiscal year 2015 and appears to be between the pessimistic and optimistic scenarios they envisioned. NSF is pursuing partnerships with universities, other institutions, and federal agencies on some projects, such as a NASA-NSF partnership on exoplanet research. NSF analysts expect an approximately flat budget out to 2019, but that could change. They’re already preparing for FY 2016, and the President’s Budget Request will come out in the near future.

For the division of astronomical sciences (AST), NSF research grant proposals had a success rate of 15-16% for both 2013 and 2014. Nonetheless, as with NASA, there appears to be a long-term decreasing trend; in 2002, the success rate was 38%. And as with NASA, this is mostly due to increasing numbers of proposals, and they’re starting to restrict the number of proposals submitted per investigator and per institution. They’re also developing strategies in case success rates drop below 10%, which would be a dire situation. I’ve been funded by NSF grants myself, and it’s stressful for faculty, research scientists, and grad students when proposals are rejected so often.

The NSF spokesperson briefly mentioned NSF “rotator” positions, which are temporary program directors who work at the NSF and collaborate with many people on a variety of policy and budget issues. The astronomical sciences has such a program, and if you want more information about it, look here.

The NSF also funds major telescopes, including the Atacama Large Millimeter Array (ALMA) in Chile, the Daniel K. Inouye Solar Telescope (DKIST) in Hawaii, and the Large Synoptic Survey Telescope (LSST), also in Chile. As you may know, scientists are making progress with ALMA and have obtained interesting results already (see below). DKIST is under construction, and construction will begin on LSST later this year. In NSF’s budget, existing facilities account for about 1/3 of it, individual and mid-scale programs are another third, and the rest of the budget goes to ALMA, DKIST, and LSST.

AAS Science Policy & Advocacy

Joel Parriott, the AAS’s director of public policy, and Josh Shiode, the public policy fellow, organized a great session on science policy and the AAS’s advocacy efforts. They gave an informative presentation about how budgets are determined and about the current budget situation for basic and applied research in the astronomical sciences. I didn’t know that the US currently funds 37% of the world’s R&D, but China is expected to overtake the US in the early 2020s.

Shiode also spoke about the importance of cross-cultural communication between scientists and policy-makers. As a scientist and as a constituent, there are many ways that you can influence your Congress members, and nothing beats interacting with them in person. If you’re an astronomer, I strongly encourage you to participate in the Congressional Visits Day. I participated in it last year (see my blog post about it), and I really enjoyed it. You can find more information here, and note the deadline on 3 February.

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There are other ways to get involves as well. You can also call or write to your Representative or Senators as well as write letters to the editor or op-eds for your local newspaper. Note that some Congress members will be receptive to different messages or to different ways of framing scientists’ and educators’ concerns. One concern scientists have these days is that some members of Congress are interfering with the peer-review process in the NSF and NIH.

Telescopes

The AAS meeting also included a session on ALMA, a Thirty Meter Telescope (TMT) open house, and a JWST town hall, as well as one for Hubble, which celebrates its 25th anniversary this spring. (I wasn’t able to attend all of these sessions, unfortunately.)

Al Wootten (National Radio Astronomy Observatory) gave a nice talk about science that is being done with ALMA so far. It’s an array of 66 12-meter and 7-meter radio telescopes, and after three decades of planning/construction, ALMA is now approaching full science operations. The US is part of a large international collaboration consisting of a partnership between North America, Europe, and East Asia. Wootten presented interesting results about observations of gas in Milky Way-like galaxies in the distant universe and of gas kinematics in protostars and protoplanetary disks. ALMA had a conference in Tokyo in December, and the proceedings will be published in a few months.

The TMT and JWST are upcoming telescopes that much of the astronomical community and the science-loving public are looking forward to. The TMT is one of the giant telescopes I’ve written about before, and it will have “first light” in 2022. JWST is scheduled to launch in 2018.

[This is my second post in a series about the American Astronomical Society meeting.]

Comet Update! Rosetta’s Philae landed, but not as planned

Now here’s what you’ve been waiting for! You really need more comet, like Christopher Walken/Bruce Dickinson needs more cowbell, so here you go…

In a blog post few months ago, I told you about the European Space Agency’s (ESA’s) Rosetta mission. Nine years after its launch and after four gravity assists, Rosetta reached the comet 67P/Churyumov-Gerasimenko and began to orbit it. On 11th November, Rosetta maneuvered its position and trajectory to eject its washing machine-sized lander, Philae, which sallied forth and landed on the comet the next day, and MADE HISTORY! (Wired‘s apt headline, “Holy Shit We Landed a Spacecraft on a Comet,” beat The Onion, which is known for that sort of thing.) Its landing was confirmed at ESA’s Space Operations Centre in Darmstadt, Germany at 17:03 CET that day.

Lander_departure

Above you can see Philae on its fateful journey, and below you can see its first image of the comet, both courtesy of ESA. The landing happened to take place while friends of mine were at a Division of Planetary Sciences meeting in Tucson, Arizona, and we and others discussed the Philae landing at Friday’s Weekly Space Hangout with Universe Today. And if you’re interested in more information than what I’ve written here, then check out the ESA Rosetta blog and posts by Emily Lakdawalla, Matthew Francis, and Phil Plait.

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From what we can tell, Philae did initially touch down in its predicted landing ellipse (its planned landing zone) but its harpoons—which were supposed to latch onto the surface—failed to fire, and it bounced! Considering how small the comet is and how weak its gravitational force (about 100,000 weaker than on the Earth), this could have been the end as the lander could then have floated away, never to be seen again. However, after nearly two hours, it landed again…and bounced again, and a few minutes later finally settled on the surface and dug in its ice screws, about 1 km from its intended landing spot on a comet 4 km in diameter. (This would be like trying to land a plane in Honolulu and ending up on another island—it’s unfortunate but at least you didn’t drown.)

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At first, it wasn’t clear exactly where Philae actually was; it could have dropped into a crater where it would be nearly impossible to find. But then based on images from the OSIRIS camera and NavCam (navigational camera) on Rosetta, ESA scientists were finally able to locate it a couple days ago. The mosaicked images above came from the OSIRIS Team, and the NavCam image below as annotated by Emily Lakdawalla, to give the larger-scale context. After its last bounce, Philae rotated and headed “east”, finally becoming settled among dust-covered ice at the bottom of a shadowed cliff. It’s not an ideal position but at least it’s not totally precarious. (They considered securing the position with the harpoons, but the momentum from firing them could push the lander back up into space, which would be “highly embarrassing” according to Stephan Ulamec, head of the lander team.)

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But the cliff situation is a problem. Philae’s battery had a little more than two days of juice in it, and once that ran out, it would be dependent on its solar panels. However, Philae’s current position only receives about 1.5 hours of light per 12-hour rotation of the comet, much less than hoped. Philae did attempt to run some of its experiments and activities during the time allotted, the battery ran late on Friday. This was @Philae2014’s last tweet: “My #lifeonacomet has just begun @ESA_Rosetta. I’ll tell you more about my new home, comet #67P soon… zzzzz #CometLanding”

Before Philae dreamt of electric sheep, it managed to collect some data using instruments on board. (See this Nature news article.) For example, Philae deployed its drilling system (SD2) as planned, in order to deliver samples to the COSAC and Ptolemy instruments, which probe organic molecules and water (and which I described in my previous Rosetta post). But ESA scientists don’t know how much material SD2 actually delivered to the lander; if the ground is very dense, it’s possible that since Philae isn’t totally anchored, it could have moved the lander rather than drilling into the surface. We do know for sure that some instruments operated successfully, such as the downward-looking ROLIS camera and ROMAP, the magnetic field mapping system.

In any case, scientists have obtained some data already while other data stuck on the snoozing lander will be retrieved later. In the meantime, Rosetta is keeping busy and continues to take observations. Philae has already been a success, and who knowsmaybe it will “wake up” when its solar panels absorb enough sunlight to recharge the batteries.

[Note that the NavCam images we’ve seen so far are pretty good, but I have heard that Rosetta scientists have much better resolution color images that are embargoed and won’t be released for six months. I haven’t confirmed this fact yet, so if you have more up-to-date info, please let me know.]

Finally, I’ll end with some comments about what some people are referring to as #shirtstorm or #shirtgate. (For more info, see this Guardian article and this blog post and this one.) On the day of the worldwide live-stream broadcast last week, Matt Taylor, the Rosetta Project Scientist, wore a shirt covered with scantily clad women. I get the impression that Taylor is a cool guy and wants to get away from the scientist stereotypes people have, but this is completely inappropriate. (And he’s worn this shirt to work before. Apparently none of his colleagues told him to leave it at home.) But it’s not just the shirt; during the middle of his broadcast, Taylor referred to Rosetta as the “sexiest” mission. “She’s sexy, but I never said she was easy.”

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We debated many aspects of this on astronomers’ official and unofficial social media, and for the most part, our community is very unhappy about this. You may say that we should focus on the science, and who cares about what this scientist wears or says when he’s excited about his mission’s success. But we have been working really hard to increase diversity in STEM fields and to achieve gender equality in science. Many aspects to working in the current scientific establishment are not particularly welcoming to women, and Matt Taylor’s shirt and poor choice of words are part of the problem. A few days later, Taylor made a heartfelt apology. As far as I know, ESA itself has not issued an official apology yet. The American Astronomical Society made a statement today (Wednesday) that “We wish to express our support for members of the community who rightly brought this issue to the fore, and we condemn the unreasonable attacks they experienced as a result, which caused deep distress in our community. We do appreciate the scientist’s sincere and unqualified apology.”

In any case, our focus is on the science and on this amazing scientific achievement. But Science is for everyone.

A Bad Week for Commercial Spaceflight

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.

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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.

Rosetta and the Comet

The title sounds like I’ll tell you a fable or short story or something. This is neither of those things, but it is quite a story! I’m not personally involved in the Rosetta mission, though I’ll do my best to tell you about it and what’s unique and exciting about this. (For you fellow astrophysicists reading this, if I’ve missed or misstated anything, please let me know.) And if you’d like more information and updates, I recommend looking at Emily Lakdawalla‘s blog posts on ESA and Phil Plait‘s blog on Slate. If you’re interested in the history and importance of comets (and about how “we’re made of starstuff”), check out Carl Sagan and Ann Druyan’s book, Comet.

Rosetta, the €1.3 billion flagship space probe (see below) of the European Space Agency (NASA’s European counterpart) has chosen to accept an ambitious mission: to chase down, intercept, and orbit a distant comet, and then send the lander Philae to “harpoon” itself to the surface and engage in a detailed analysis. Rosetta is obviously named after the Rosetta Stone in Egyptian history, and Philae is named after an island in the Nile. Rosetta and Philae are hip spacecraft: they even have their own Twitter accounts—@ESA_Rosetta and @Philae2014, respectively. They should be careful when examining the comet below its surface, because if it’s anything like Star Trek, they could find an ancient alien archive in the center! (Fans of the “Masks” episode will know what I’m talking about.)

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Comets are literally pretty cool. They’re clumps of ice, dust, and organic materials with tails that are hurtling through space. What is this comet Rosetta’s pursuing? It’s known as Comet 67P/Churyumov-Gerasimenko, named after a pair of Ukrainian astronomers who discovered it in 1969. 67P/C-G looks like a mere blob from a distance, but it’s 4km in diameter and lopsided with two barely-attached lobes that make it look like a rubber duck from certain angles. “It may be an object we call a contact binary which was created when two smaller comets merged after a low-velocity collision,” said mission scientist Matt Taylor, or it may have once been a spherical object that lost much of its volatile material after encounters with the sun. It also has plumes of dust and gas (from sublimated ices) erupting from the surface, which has a temperature of about -70 C. (The montage of images below are courtesy of ESA/Rosetta/NAVCAM/Emily Lakdawalla.)

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Comets tell us about our past, since they’re thought to have formed in the cold of the outer solar system 4.6 billion years ago. They also yield information about the formation of the solar system and about the role of comets in delivering water and organic material to Earth in its history—possibly influencing the origin of life here. Cometary impacts are known to have been much more common in the early solar system than today. There may be billions of these dirty snowballs (or icy dustballs) orbiting the sun, and thousands of them have been observed. Prior to Rosetta, three comets have been analyzed by space probes: Halley’s comet by ESA’s Giotto in 1986, Comet Wild 2 by NASA’s Stardust in 2004, and Comet Tempel 1 by NASA’s Deep Impact, which slammed into it in 2005. The diagram below (courtesy of ESA/Science journal) shows the orbits of Rosetta and 67P/C-G. The comet has been traveling at speeds up to 135,000 km/hr, and Rosetta had to use flybys of the Earth and Mars to maneuver onto the same orbital path. Rosetta will be the first mission ever to orbit and land on a comet, so this is really an historic moment in space exploration.

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On 11 November, Rosetta will be in a position to eject the Philae lander from only a couple kilometers away. Philae is 100 kg, box shaped with three legs and numerous instruments for experiments (see below), and was provided by the German Aerospace Research Institute (DLR). NASA scientists talk of the “7 minutes of terror” as the Curiosity rover descended to Mars, but Philae’s descent will take hours. Note that 67P is so small and gravity is so weak that the lander would likely bounce off, which is why it needs the harpoons as well as screws on the legs to bolt it to the surface. If the landing is successful—let’s cross our fingers that it is—it will perform many interesting experiments with its instruments. For example, CONSERT will use radio waves to construct a 3D model of the nucleus, Ptolemy will measure the abundance of water and heavy water, and COSAC will look for long-chain organic molecules and amino acids. COSAC will also detect the chirality of the molecules and maybe determine whether amino acids are always left-handed like the ones on Earth. (“Chirality” means “handedness”. I think the only other time I heard the term was for the spin statistics of spiral galaxies.)

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Let’s hope for Rosetta’s and Philae’s success! I’ll update you on this blog when I hear more information.

Extreme Space Weather Event #23072012

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)!

A less threatening solar storm on the Sun

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”

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.

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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.

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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.