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Congratulations!!! You must be so psyched! I assume you’ll be applying to astronomy PhD’s? What’s your research interest?

Space force. Oh boy

This is probably a worthy lesson in the intractability of basic tenets of physics…

I was honored yesterday to speak at my class’s commencement. Probably time to start thinking about what’s next 🤓

What’s shakin’ on Mars?

Thanks to geodesic studies into the way Mars wobbles (nutation - feel free to send questions if you want to know more about this), it seems like NASA’s figured out that Mars actually has a liquid core! This is exciting but how on Mars could we possibly learn more?

Seismology.

On Earth, most earthquakes are the result of tectonic plates moving around. They are a physical manifestation of the internal planetary energy seeking a way out. On Mars there are no tectonic plates. This is a fascinating and broad subject within planetary geology but the fact doesn’t mean Mars is without its own seismic activity: volcanoes also produce quakes.

On Earth, seismic activity around volcanoes can be seen as a precursor to volcanic activity. Interestingly enough, this could also be true on our red neighbor:

(Image credit: E. Hauber, P. Brozˆz, F. Jagert, P. Jodlowski, T. Platz, Very recent and wide-spread basaltic volcanism on Mars, Geophys. Res. Lett. 38, L10201 (2011))

The dark green dots on the image above indicate what Hauber et al. (2011) believe to be very new terrain on Mars. Less than 100 million years old. If both this and NASA’s conclusion regarding a fluid interior are true: Mars may not have erupted its last yet. Both of these things would seem to indicate a current stockpile of internal energy.

What’s more? Methane has been detected numerous times. Since methane breaks down very quickly, this means there is something on Mars currently producing methane. It’s probably worth noting that one way it’s created (geologically) is when underground water mixes with olivine rock. It can then emerge from volcanic activity.

In a few months NASA will be launching the InSight mission. The landing zone is Elysium Planitia, an extensive volcanic region.

It’s possible when NASA takes the Red Planet’s pulse, they will find a planet full of geological life. If so, this could also indicate a powerful way to investigate the interior of the planet in the future. In the plots I made at the top you can see Earth and Mars next to each other. I tried to scale them relative to each other. On Mars you can see that we have an idea of what’s under the crust, but until we actually go and start detecting seismic activity, we won’t know.

Who cares you say? Well you should: if Mars is still geologically active it could shed light on why Mars lost its magnetic field, (most of) its atmosphere, any oceans it may have had and therefore its potential habitability. Furthermore, learning these things will give us a powerful new way of thinking about terrestrial planets, how they evolve and what it might be like on other worlds far from us in other star systems.

3D Cave Scanning: Prospects

Remember that scene from Prometheus where the two flying probes are sent into the halls, laser scanners flashing every which way?

That’s a real thing now… well sort of.

The European Space Agency has a program called PANGAEA which is aimed at developing geology training programs for astronauts. As a part of this program a new technology was recently deployed and tested in Spain’s extensive La Cueva de Los Verdes lava tube. It’s actually a pair of technolpogies called the “Prgasus Backpack” and the “Leica BLK360″.

The Pegasus Backpack is a wearable “3D mapper”. This is something that could be used to map out street views similar to the Google Street View. What makes it so cool though is that the backpack doesn’t require a satellite connection, enabling it for use inside places with poor connectivity.

The Leica BLK360 is a LIDAR camera (Laser Imaging, Detection and Ranging). What LIDAR does is it shoots out a beam of laser light and thanks to the speed of light, is able to get an extremely accurate measurement of the distance from the camera the laser beam hit something and bounced back to the LIDAR camera. The camera detects this bounce back and does it again many more times, putting together a scan of the surrounding space: essentially an image of the room you’re in (or for many spacecraft, of the topographic features of the planetary surface below it). 

When combined, as researchers with PANGAEA did, they were able to go deep inside the La Cueva de Los Verdes lava tube, away from both satellite connections and light, and create a detailed, 3D map of the entire lava tube.

Here is a fly through:

(The lava tube has a total length of about 8 km and detail goes all the way down to a few centimeters in resolution)

Why is this important? As exploration of the Solar System continues on places like the Moon and Mars (Venus too if I could have my way), we find evidence of dynamic geologies that could take research below the ground. The Moon, Mars and Venus all have lava tubes. This new method could enable detailed exploration of subsurface locations on many of these worlds like how they formed.

It’s also worth noting that if something like a lunar base were ever created, the lava tubes on the Moon would present a stable, radiation-protected region that could be used to house astronauts.

(Image & video credit: Vigea – Tommaso Santagata and ESA respectively) 

Rest in peace Professor Hawking. You’ve been an inspiration to us all. Your writing is what originally brought me into science. I don’t think I’m alone 

The Value of Mars Exploration

(An unedited reflection on science and my time studying it)

The value of Mars exploration is great, but perhaps also elusive. The “red planet” holds 4-billion years of geological history to explore, the surface of which is yet to be scratched. In order to appreciate the value of exploring Mars however, you need somewhat of a historical perspective. Some of the most groundbreaking advances in technology (and therefore quality of life) were not the result of predetermined intent. Almost every discovery made, has been a surprise. Therefore the value of exploring Mars, is in its own right a mystery. This question can be approached in terms of potential; It is entirely obvious that a place as large and old as Mars has an intriguing set of clues to fundamentally important questions: why do planets evolve differently from the Earth, how did Mars lose its atmosphere, was there ever running water on the surface of Mars, and are we alone? So in a sense we can assign value to exploring Mars based on the questions we intend to explicitly explore. Even this won’t do full justice to the actual value that would come from exploring Mars, for this assumes that we know what questions to ask. The safest way to appreciate the significance of exploring this place is to look back and see how scientific exploration has always turned out.

It is somewhat ironic that in order to justify science, historical evidence needs to be recalled. The nature of scientific inquiry is most often serendipitous. For example, when Isaac Newton sought to explain how it was that planets moved throughout the Solar System, he invented calculus. In doing this Newton almost certainly didn’t expect to also invent a branch of mathematics that empowered humanity to create computers, robotics, and even fly supersonic jets across the sky. Yet in a sense, these are all distant relatives of astronomy thanks to their common origin in calculus. This example, although dramatic, has a thread of truth that runs through the entire history of science. Even in cases of profound theoretical prediction, like the prediction of the Higgs Boson, discovery is still inevitable both in the sense that a theory is never complete in its prediction, but also in the sense that scientific consensus will not be reached until after a discovery and so this still represents a collective epiphany.

The value of exploring Mars is just the next piece in this thread of serendipitous adventure. Qualifying this exploration on the word “why” radically devalues the magnitude of our ignorance of that world, and of the amount of exploration it would require to “conquer” it; For to explore Mars, we must explore our own potential in ways that have never been done before. We have to explore the ways space affects us biologically, we need to explore our potential to look at what is currently impossible, and engineer the impossibility away. Martian exploration provides us with so many challenges that the value of the exploration is only partially about the planet itself. Is the point of weightlifting to make a heavy object inhabit space a few feet higher than before? The value of exploring Mars is obviously encompassed in all the mystery hidden away in the 4-billion year history of the Red Planet, but there is more: the value of exploring Mars is in all the ways it’s currently difficult, and how those things no longer will be afterwords. In a sense, a post-Mars humanity will have grown in all the ways where now Mars exploration challenges us (i.e. a lot). Exploring Mars, means radically empowering humanity. It is important to therefore look at where problems arise that make Martian exploration difficult, for the solving of such problems is therefore the minimum boundary on the value of exploring Mars.

By defining the values of such work in this way, we inevitably draw our appreciation for the benefits in terms of what the costs are. Space exploration in this sense is an investment in ourselves. So therefore in order to really narrow down how to value the exploration of Mars, we need to first explore how this endeavor is costly. There are obviously many ways in which something like this is expensive, most not defined explicitly in terms of financial cost; For example: there could be physical costs, political costs, and even spiritual costs etc. Finally it is critical to understand that just as the true values of science are often serendipitous in nature, so too can the costs be unexpected. Therefore the following suggestions are meant as the minimum ways in which such a voyage may cost humanity.

It makes sense to begin with the most obvious way in which a voyage to Mars will cost us: financially. A trip to Mars in any aspect will incur exorbitant expenditure on behalf of the peoples and governments sponsoring such a voyage. A common saying is that for every pound launched into orbit it costs “$10,000”. This may not be exactly accurate but it captures the point. Every aspect of space exploration is tremendously costly and this begins with the fact that to even get to space, massive amounts of money need to be put into a launch vehicle. This is true for Mars too. There are numerous ways to make the journey, whether by a Cycler orbit, a Hohmann Transfer or through some other method not yet clear to us. For each, here will be a cost. For example, in order to get to Mars by using a Hohmann Transfer you need enough fuel to not simply get your astronauts and supplies into space, but to stretch your orbital trajectory so that it goes from Earth to Mars where you then use more fuel to slow down. The amount of fuel to do this is tremendous. Furthermore, since this method means simply orbiting your way into a Martian gravity well, you are only going to move so fast. Therefore a crew must be able to survive in space for that long. When you think about how every pound launched into orbit is that much more of an expense, and how much food you eat in a few months: it’s obvious as to why the cost rises quickly.

So obvious is it that a voyage to the Red Planet would cost a lot of money, that the case hardly needs to be made. Focus therefore should be on the ways that costs could surprise us. For example, if there are long-term consequences of being in microgravity for extended lengths of time we aren’t yet aware of. This is something that we may have figured out but until the experiment is actually done, we just won’t know for sure. Furthermore, it is clear that if something were to go wrong and lives were lost  because of this mission(s), politicians could easily face consequences. Just like war efforts, grand explorations missions may be tied to the identity of a single politician for whatever reason. This was obviously the case with President John F. Kennedy thanks to his “We will go to the Moon” speech. If something were to go wrong then a highly visible exploration effort could become a prime target for political fodder. The Apollo missions are generally regarded as success stories but even so when Kennedy’s old political opponent Richard Nixon ascended to the Presidency, NASA found itself ordered to dismantle the Apollo missions and begin focusing on the construction of the Space Shuttle – often regarded as a retreat from NASA’s ambitious human missions.

Due to the volatile nature of politics, NASA may be forced to change their approach halfway through a directive: should we go straight to Mars or should we go to the Moon first? One administration may want one thing and another a different one. This constant changing of direction could not only force NASA to spend money on things that have already been accomplished in different ways, but it could repeatedly drive away potential contract bidders. Less options will almost certainly result in not having the most favorable option at least once, and therefore drive up costs. A private contractor cannot be expected to always bear the brunt of political misfortunes on behalf of a government agency.

This potential for these costs to be unexpectedly driven up is representative of the risks taken by the private sector. When a contract is set to outlast an officeholder the contractor is taking a gamble that the next officeholder will continue honoring said contract. The risks of space missions paying off are therefore economically uncertain. Since budgets are points of intense debate (and partisanship) in Congress, whether or not a company will get paid on time (or at all) depends on the year. The relationship extends to taxpayers: NASA missions have historically contributed wonderful spinoff technologies that have helped drive the economy and society overall.

The space program for example, has contributed many cornerstone advancements of the modern world: whether it’s communications satellites, CATScan technology or smoke detectors. Without a doubt the world would be a dramatically different place today if it weren’t for these things. Hindsight makes it clear the scientific investments that led to such technological achievements were wise ones. It should be emphasized that this payoff wasn’t and still isn’t clear beforehand. Many such advancements however were the result of risks that  astronauts faced on their missions led to humanity radically pushing its boundaries to specifically find solutions for those astronauts.

With this in mind it’s clear that there is a duality to the risk-payoff nature of a mission to Mars. Like previous astronauts, Martian explorers would face a list of known risks (and likely numerous unclear ones). It will take tremendous effort on the part of scientists and engineers to solve the numerous problems people would face on their way to Mars, but if these problems are solved, the technical payoff would reverberate back to Earth. This is an inevitable benefit of the space program. Simply by understanding the physical risks inherent to astronauts it’s possible to begin inferring the sorts of benefit Earth would reap by their solving; For example one solution being worked on at the EVA laboratory at MIT is the BioSuit. This suit utilizes a system of small springs built into the suit to provide pressure to the body, rather than an astronaut suiting up inside a balloon. Professor (and previous Deputy Administrator of NASA) Dava Newman is working on this concept. She says that there is potential for such a spacesuit to help both victims of cerebral palsy and strokes:

“We have been working with colleagues at Children’s Hospital in Boston, Harvard’s Wyss Institute, Boston University, and Draper Laboratory to see if we can use our technology and engineering designs to help infants with brain damage that affects motor skills, children with cerebral palsy, and stroke victims, who typically lose motor skills on one side of their bodies. The idea is first to use BioSuit “sleeves” with builtin sensors on the legs to measure movements—to understand, for instance, how much motion and kicking by infants is typical and compare that with the limited kicking and motions of children with cerebral palsy. The next step—a big one—is to add actuators that can enhance and direct movement. In the case of cerebral palsy and stroke victims, that would be a way of giving back some of the lost motion. People with cerebral palsy expend a lot of energy moving and have stiffened muscles; our BioSuit technology and know-how could guide movement and enhance mobility to make it more efficient. And because the brains of newborns are still so plastic, enhancing the natural kicking of infants with potential motor problems from brain damage might actually reshape the motor programs and partly “heal” their brains.”¹

If true, it’s clear that there is incredible potential to help humans on Earth, even in the minutia of a mission to Mars. Although astronauts face personal risks on such missions, the risks of not undertaking missions like this in general span all of humanity. To not go to Mars is therefore a planetary risk, though it’s not explicitly clear how, and to what magnitude. If it were clear this would probably be a somewhat more common justification. To not go to Mars is to stunt human potential, especially in the intersection of biology and technology: a place where further understanding and capability have great potential to change lives.

It is therefore difficult to divorce the idea of sending astronauts to Mars from the risk of becoming uninvested in relevant scientific exploration. Space exploration is inspiring and motivating. Extraordinary efforts go into advancing space science and it requires such extraordinary efforts. Rare is it that such difficult problems attract swaths of young minds to the STEM fields. Space exploration however, is one such rallying point – perhaps the best. On several levels this is relevant: students who go work in space exploration that contributes civilization-wide spinoffs, students who go into STEM intending to work in space exploration (but maybe end up somewhere else), and students inspired by space exploration but don’t end up in the STEM fields. The first two groups contribute to the global infrastructure, technology and economy directly: one from whatever spinoffs result in the space program and the other by working directly on terrestrially-sourced problems. The third group may not directly contribute to technical achievements but would almost certainly provide the political support NASA and various science agencies need in order to attract public funding. This is all due to the technical and economic feedback loop that exciting exploration programs like a mission to Mars would result in. Were we to not go to Mars, this feedback loop would obviously shrink or die to some extent. This is a risk of not exploring Mars.

Considering all the different ways in which risks and benefits are intimately tied in space exploration, we can assume that by facing the risks of a mission to Mars, we stand to gain quite a lot. Nevertheless it is impossible to know exactly what benefits would come of it. Societies have never faced civilization-wide detriment for indulging the spirit of exploration (to my knowledge), however. It’s important to then really face the idea of whether or not a mission to Mars is truly justified. It will certainly take a lot of money and a lot of physical risk on the part of the astronauts. Fundamentally these are the prohibitive risks. Perhaps it would be useful in light of the benefits of scientific exploration to frame the question as “what are the risks of not exploring Mars?”

On the other hand greater risks are taken with far less scrutiny: is invading another country a risk? It’s almost certainly going to cost more money, more lives and have far more geopolitically divisive consequences than a mission to Mars. Realistically, there are many activities conducted by or on the behalf of governments and nations that incur damage to economies and lives than space exploration. Space exploration is one of the few things that can be done that will almost certainly benefit the global economy, infrastructure, quality of life, and unite disparate political groups. The risks are almost inscrutably small to the average person. The only consequential dangers are to the astronauts on the mission – and these people are almost unanimously hailed as heroes as they voluntarily put humanities best foot forward into the dark, bringing enlightenment back to us. It is clear that Martian exploration is justified.

This is a common perspective across the fields of science (though maybe not unanimous). The issue of whether or not space exploration is justified (and specifically a mission to Mars) seems to be more controversial to the “uninitiated” in the STEM fields. Assuming this to be true, it isn’t clear to me why. It could be true by definition if such people were in part brought into the Stem “fold” by being inspired by things like space exploration (being a part of that “feedback loop” mentioned above) or science fiction. Like parents, scientists often dote on their research, yet a new parent is hardly ever asked “what is a newborn baby good for?”. 

Before starting my astronomy degree, I was a humanities student. Although intrigued and supportive of the space program, I approached problems in fundamentally different ways. I would ask “What’s possible?” in the context of modern technology. As a scientist (sort of) I find myself asking questions more akin to “How can this be made possible?”. I don’t know exactly why this perspective shift happened but it certainly occurred (probably gradually). As a longtime lover of science fiction, my core sympathies and hopes were always in entirely in favor of the space program. The change in perspective as I see it, is probably more fundamental. Among the scientists I’ve spoken to, if going to Mars were entirely up to then it would be only a question of how to make it happen. Science is fundamentally explorative in nature. Having trained my mind to rigorously indulge intellectual curiosity over the last four years has possibly promoted shift in perspective. After studying astronomy and physics I can now acknowledge that I do see the world differently than before. The mysteries are different, and mystery itself means something different. Mystery is no longer a wrench in the machine of the world, a source of impossibility, ignorance or magic. Mystery is now a target, a destination – the magic, in a sense, is still there. It is no longer the superstitious fear of walking a minefield but the magic of opening a gift, traveling to a new place, and in doing so uniting the universe I see with the internal growth from knowledge and experience.

(Top image credit: NASA

Image & quote source: Newman, D. (n.d.). Building the Future Spacesuit. Ask Magazine.)

Did you know the government of New Mexico still considers Pluto to be a planet? In fact March 13th is “Pluto Planet Day”! So mark your calendars, it’s coming up.

Gravitational Forecasting

On Earth the atmosphere accounts for roughly 1/1,000,000th of the mass of the planet (i.e. not much at all). On Jupiter however, it’s a different story.

The horizontal bands that cross Jupiter have long been known to be giant jet streams with forces going up to 100 times that of any hurricane on Earth. How similar are these atmospheric forces to those found on Earth? It turns out, probably pretty different.

Researchers from NASA’s Juno mission team (led by Professor Yohai Kaspi) have found that the gravity measurements from their spacecraft indicated a strangely deformed gravity field. In fact, they found that about 1% of Jupiter’s mass is in its extensive atmosphere. This means that a gravitationally detectable amount of mass is moving in these currents. The bands (which are visible with an 8″ or so telescope!) on Jupiter actually extend as far as 3,000 km below the surface. Impressive.

I admit to writing a rather “clickbaity” name for this post but who’s to say, perhaps some daring planetary scientists will try to come up with a system of weather forecasting based on gravitational anomalies? The future is now!

(Image credit: NASA/SWRI/MSSS/Gerald Eichstadt/Sean Doran)

I will definitely be watching the skies! This will be an exciting reentry to see.

New Astrophysical Object: The Synestia

There’s been quite a lot of debate going on regarding how exactly the Moon formed: most seem to agree that when a Mars-sized planetary object struck the Earth, somehow the debris thrown into space formed into the Moon.

There’s actually quite a bit of evidence this is true: chief of which are the similarities in isotopic ratios of various elements found in Apollo samples and terrestrial rocks. We don’t, however, have a good idea of what the chaotic Moon-formation time looked like. Researchers from Harvard (and UC Davis) have just proposed a new theoretical object, called a “synestia”.

The synestia would look “donut-like” in shape (as shown above). It would be made of rocky materials liquefied during a planetary collision. How does this work?

• An impact injects kinetic energy into a planetary body, increasing the planet’s temperature. If you think of this on a molecular level, the molecules are beginning to move faster. 
  
• Now, zooming back out, think about how a planet rotates: because this rotation is axial, an equator needs to be moving faster than the poles for the surface to be continuous. 
  

Now lets put those two things together: The material of the planet is moving faster due to an increased temperature, and the equatorial material is moving even faster.

Bingo. The velocity of the liquefied material at the equator, it turns out, actually begins to intersect with the velocity required of a basic Keplerian orbit!

This is a controversial problem with more traditional approaches to Moon-formation theories where most impact scenarios actually imply that there isn’t enough energy for debris to reach orbit around the Earth.

It’s from these synestias that it’s thought things like the Moon may have formed out of.

According to a model built by researchers Simon Lock and Professor Sarah Stewart, these objects exist during planetary collisions and can be potentially seen by astronomers. Synestias could potentially explain the great diversity of ring and satellite systems that exist: from the Moon the the lopsided rings of Neptune. This research is both promising and extremely exciting!

Learn more here

(Image credit: Sarah Stewart/UC Davis)

Incredible Infrared Image of the Central Molecular Zone

This is the central region of the Milky Way where the black Hole Sagittarius A* resides. The image was taken by the Spitzer Space Telescope.

(Image credit: Spitzer/NASA/CfA)