Off to Mars — to stay

Could it make sense to take a one-way trip to Mars? This notion has been floating around for years, but it got some recent press when Drs. Schulze-Makuch and Davies published a paper titled “To Boldly Go: A One-Way Human Mission to Mars.” Their thesis is that this might be the solution to several of the barriers to a crewed mission, providing among other benefits a major reduction in mission cost (up to 80% reduction, which is pretty dramatic!). This can only be accomplished by shifting our perspective on what such a mission is: not a there-and-back-again jaunt like a trip to the Moon, but the establishment of a sustained presence on Mars, paving the way for future colonists and expeditions. Schulze-Makuch and Davies declare that:

“… to attain it would require not only major international cooperation, but a return to the exploration spirit and risk-taking ethos of the great period of Earth exploration, from Columbus to Amundsen, but which has nowadays been replaced with a culture of safety and political correctness.”

The initial reaction to a one-way trip concept is often one that assumes that the humans involved would immediately expire at the end of their mission. “One-way” sounds like “suicide”. But it’s not more of a “suicide” than inhabiting Earth, which is just as much of an ultimate death sentence — we just don’t think of it that way. Well supplied and informed, an expedition to Mars could survive for a long time, albeit in a harsh and demanding environment. They might not live as long as they would on Earth — or they might live longer; no one’s going to get hit by a car on Mars! And just think of the amazing accomplishments this group of 21st-century pioneers would attain, in technology and in science, and also in poetry and psychology: making Mars a human location, not just a light in the sky.

This short paper is definitely worth reading to see how Schulze-Makush and Davies set out the arguments for, and the conceptual design of, such a one-way mission. I was heartened to see their clear statement that “No base on the Moon is needed to launch a one-way human mission to Mars.” This is true of any mission to Mars, but has become somewhat lost in the various Constellation program discussions.

If there really were an opportunity to volunteer for a one-way mission to Mars, where you’d live out your days in a “cave-centered biosphere”, exploring and discovering and serving as a pathfinder for future advances — I’d sign up in a heartbeat. It’s difficult to think of any more important and meaningful goal to which I could devote my life here on Earth. (I know some, or all, of you will disagree with me on this, which neither offends nor dissuades me in the least. :) )

Curiosity Cam questions

On a tip from my officemate, today I checked out the live camera feed from the clean room next door where our next Mars rover, the Mars Science Laboratory (or MSL), is being tested. MSL doesn’t launch until next fall, but they’re busy putting it through its paces right now to ensure that all of the instruments work as expected. It’s in a clean room so that we can minimize the amount of terrestrial biota it picks up prior to launch. We’d hate to inadvertently inject our own life into the pristine Martian environment — especially if we then detected it and thought it could be Martian!

As I write this, at 10:30 p.m., a technician in his bunny suit is walking around the rover, tinkering with connections and still hard at work. The video is dubbed “Curiosity Cam” because it is alliterative and because MSL acquired the name “Curiosity” as the result of a naming competition (I prefer simple old MSL).

But earlier today when I tuned in, JPL was also offering a live chat to accompany the video. Two anonymous folks in our newsroom were fielding any and all questions posed by anyone who dropped in. At first glance it seemed a bit dull — but then I started reading the comments and quickly became sucked in. How can you help but want to answer the questions of the curious public? Here are some excerpts. (Note that people who connected but didn’t log in via twitter or facebook, including me, were assigned generic “ustreamer” ids.)

The most common question (which maybe you have as well) is what the flashing blue light means. I thought it was probably just a visual signal that testing was in progress… but learned from the chat that instead it means that power is flowing to the rover.

ustreamer-43285: i’ve had 2 questions answered by jpl…this is awesome.
ustreamer-61986: i want to work for NASA!!!
ustreamer-01212: me too
Giati: me 3
ustreamer-25131: me 4
ustreamer-59789: Hell yeah, just no way im as smart as these guys. Awesome]
ustreamer-75761: yep nasa beats all other space agencys by a mile

Not a kilometer?

The two JPLers officially answering questions were named NASAJPL and NASAJPL-1. I was repeatedly impressed with how they fielded all sorts of questions, with a polite and informative tone, no matter the question.

ustreamer-33518: i hope this rover doesnt get stuck do you have a system to stop that happening?
NASAJPL: 33518, the rover’s six 20-inch wheels are designed to help maneuver out of such a situation.

One individual, 59789, was really taken with speculations about the upcoming astrobiology-related press conference on Thursday. The link he/she posted certainly falls into the “speculation” genre. I couldn’t resist chiming in to help out.

ustreamer-59789: Not at all. Thursday meetng will put that to rest. Nasa revealing they found biological life on Titan
ustreamer-59789: http://current.com/technology/92832052_story-of-the-century-nasa-may-announce-thursday-to-have-found-life-on-saturns-moon-titan.htm
NASAJPL-1: There are a lot of rumors about the Thursday briefing. It will NOT be an announcment of finding extraterrestrial life.
ustreamer-69544 (Me): There is a lot more to the field of astrobiology than just finding current life — we want to know about conditions conducive to life, and all of the chemistry involved, too.
NASAJPL-1: Repeat: it will NOT announce the finding of life on Titan. It’s too bad people out there are trying to get attention by running false stories.
NASAJPL-1: 69544 That is correct!

Then the questions started getting more and more interesting:

ustreamer-75761: wish ion drives were being used it would be a whole lot faster then currnent tech
ustreamer-69544 (Me): 75761, ion drives accelerate much more slowly than chemical rockets. They are good for very long trips but not for trips to Mars.
ustreamer-49140: 69544 … I understand that. But it’s still bewildering, with all our tech we have to send a FLEET of probs to mars to find out if theres life there. Surely it can be done with a single probe ?
ustreamer-69544 (Me): 49140, no one knows how to search the whole planet with a single spacecraft. But we learn more from each one sent!
ustreamer-49140: 69544. I agree, but we shouldent have to travel ALL over mars in an effort to find life. Just as someone sending a probe to earth would find life no matter where the probe landed.
ustreamer-69544 (Me): 49140, if life were as prevalent on Mars as it is on the Earth, you’re right, we would already have found it!

… and even relevant to geology!

ustreamer-02837: is it believed the lanscape on mars was created by water?
ustreamer-69544 (Me): 02837, the Martian surface has been shaped by ancient water, and aeons of wind, and episodes of volcanism.

ustreamer-77218: Earth is much bigger than Mars, but about 70 % of the Earthen surface is covered by water. On Mars there is 0 % covered. How much land compared to earth is it on Mars?
ustreamer-69544 (Me): 77218, great question! In fact the land surface on Mars is quite close to the land (non-ocean) area of the Earth.
ustreamer-77218: Thank’s “US-69544”. =) And Moon? about half of Mars?
ustreamer-69544 (Me): 77218, it looks like the Moon’s surface area is about 1/5 that of Mars.

(Actually, my quick math was a bit off — it’s between 1/4 and 1/5 that of Mars.)

After a while I started to wonder if NASAJPL and NASAJPL-1 would realize that I too was at JPL… and then I decided to get back to some real work. But wouldn’t it be fun to be the JPL expert fielding these questions?

No surfing on Titan

The discovery of lakes on Titan in 2006 has fueled many imaginations and also inspired a lot of questions. One of those questions was presented today at the Lunar and Planetary Science Conference (LPSC) by Ralph Lorenz. We’ve observed that these lakes are filled with liquid hydrocarbons (such as methane), so of course they are a bit different from the lakes we find on Earth. But one curiosity is that in all of our observations, we’ve never seen any evidence of waves in these lakes.

We observe lakes on Titan using radar, to penetrate through its thick atmosphere. Radar returns are sensitive to surface roughness, so waves on lakes (among other things) usually show up quite clearly. (We use this on Earth, too; see ocean features observed by Seasat.) But so far, all of our images of Titan lakes have turned out to be entirely flat and glassy: dark surfaces rather than bright ruffled ones.

Why is this? We know there are lakes and we know there are winds, so why no waves? Scientists have attacked this problem by measuring the minimum wind speed needed to kick up waves for (water) lakes on Earth (1-2 m/s) and then adjusting it for Titan’s thicker atmosphere (down to 0.5-1 m/s). Global Climate Models (GCMs) for Titan do suggest that surface winds get above this level during the local summer. Unfortunately, right now it is winter in the south, and there’s where the largest lake (Ontario Lacus) is located. Summer won’t come again until after the Cassini spacecraft’s current Equinox mission ends; the subsequent seven-year Solstice mission might have better luck.

But there could be another reason for the lack of lakes as well. Spectrographic observations of Ontario Lacus suggest that it contains not only ethane and methane but also a lot of dissolved solids (propane and others). These “tarry dregs” would likely increase the lake’s viscosity, making it even harder to ruffle.

Ultimately, until we splashdown into the lake itself, we may not know exactly why the surface stays so calm. Mission concepts such as the Titan Mare Explorer and the Titan Submersible Explorer are designed to do just that.


More info (LPSC 2-page abstracts, PDF):

LPSC: Past water on Mars, future landing sites, and Moon-mapping

Today was the first day of the Lunar and Planetary Science Conference in The Woodlands, TX (north of Houston). Here are three highlights from today’s sessions:


Ray Arvidson described sulfate-enriched sand observed by the Spirit rover (“still a rover, not a lander,” he insisted). The sulfates are interpreted as forming in a warm, moist environment created by the ancient volcanism in the area. There are several distinct layers, and the sulfates are found at the bottom, supporting a hypothesis that this area experienced periods of high obliquity (axial tilt) that caused this near-equatorial region to be much colder (and covered in snow).

“Thus while embedded on the side of Scamander crater Spirit has uncovered evidence for two timescales of water-related processes: formation of aqueous deposits associated with early volcanic activity and subsequent continuing redistribution of soluble species associated with orbitally-induced climatic change.”

Two-page abstract (PDF): “Recent Scientific Results from Spirit’s Observations of Sulfate Sands on the Side of Scamander Crater, Columbia Hills, Mars” by Ray Arvidson and the Athena Science Team

By the way, if you’re worried about Spirit, you can browse the latest Free Spirit news. Although it’s been declared a “stationary science platform”, chances are very good that when spring returns and there is more power available from its solar panels, the Spirit team will again see if they can extricate its wheels.


John Grotzinger provided an update on the upcoming Mars Science Laboratory (MSL) mission (due to launch in 2011) and what landing sites are most attractive in terms of searching for evidence of past life. MSL will be able to search for ancient biosignatures in terms of complex organic molecules, unusual isotope ratios, and unusual rock textures. (I was particularly interested in the last point, since it relates to my work on detecting structural biosignatures by analyzing rock textures.) The original four landing sites being considered are Holden Crater, Mawrth Vallis, Eberswalde Crater, and Gale Crater.

“While each site has its own particular strengths, they share in common two very important attributes: definitive evidence for the former presence of water as seen by either mineralogic or morphologic features (or both), and the presence of prominent stratigraphic sequences, hundreds to thousands of meters thick in some cases, suggestive of sedimentary rocks.”

On January 4, 2010, the MSL Landing Site Steering Committee voted to add two new candidates: Northeast Syrtis and East Margaritifer. Stay tuned for more news as they whittle these finalists down!

PDF: “Mars Science Laboratory, Preservation Potential of Biosignatures and Environmental Records, and the Attributes of Promising Landing Sites” by John Grotzinger


And finally, I also attended at least one non-Mars talk! Richard Vondrak gave an overview of the current status of the Lunar Reconnaissance Orbiter (LRO), which began its science observations last September. The goals of this mission are to identify safe landing sites, locate useful resources, measure the radiation environment, and test a Synthetic-Aperture Radar (SAR) device.

After a four-day cruise, LRO arrived at the Moon and settled into a commissioning orbit for three months. This highly elliptical orbit took it as low as 30 km above the south pole (periselene, its closest approach to the Moon) and out to 216 km away at aposelene. It then transitioned into a circular orbit (at an altitude of 50 km) for its 12-month nominal science mission. This orbit, interestingly, takes a lot of effort; if LRO does not periodically fire its thrusters to maintain it, the spacecraft will lose 15 km of altitude per month and shortly crash into the Moon. While that was an intentional activity for LCROSS, LRO would prefer to achieve a longer lifetime and even to win an extended mission.

The amount of data being returned by this mission is phenomenal. Due to its relative proximity and a dedicated ground station, LRO is able to return much more data than any Mars mission; in its first 3 months it collected 55 TB (to be released by the Planetary Data Service on March 15) and by the end of a year, it will have accumulated more than 140 TB. By that point it will have depleted its station-keeping fuel and then revert to an elliptical orbit. But no doubt it will still be eager to collect more data!

PDF: “The Lunar Reconnaissance Orbiter at the Midpoint of the Exploration Mission” by Vondrak, Keller, Chin, and Garvin


I also really enjoyed Ron Greeley’s Masursky lecture, titled “Shifting Sands: Planetary Atmosphere-Surface Interactions.” There are so many truly beautiful aeolian features on Mars!

Bilingual exoplanet coverage

Others in my French Translation class have chosen works of literature for their translation projects. Me? I chose a recent article announcing a terribly exciting discovery: the first rocky exoplanet! (As opposed to the “hot Jupiters” and other large gaseous planets.) I found this article on the radio-canada.ca website:

Une première exoplanète rocheuse
(16/9/2009)

Près de 15 ans après la découverte de la première exoplanète en 1995, des astrophysiciens européens ont annoncé avoir trouvé une toute première planète de type rocheuse autour d’une autre étoile que notre Soleil. L’exoplanète Corot 7b avait été observée en début d’année, mais sa composition n’avait pu être établie à ce moment. Sa constitution n’est pas l’unique particularité de Corot 7b. Elle est également la plus petite jamais découverte, avec un rayon équivalent à 1,8 fois celui de la Terre. De plus, c’est la planète la plus proche de son étoile. Elle en fait le tour en seulement 20 heures (correspondant à la durée de son année). Le spectrographe HARPS installé sur le télescope européen de 3,6 mètres de la Silla, au Chili, a également permis d’établir que sa masse correspondait à 4,8 fois celle de la Terre.

Vie impossible
La température dépasse 2000 degrés Celsius sur la face éclairée, puisqu’elle est située à seulement 2,5 millions de kilomètres de son étoile. L’astre pourrait avoir des océans de lave à sa surface. L’autre face, plongée dans la nuit, est glaciale, avec des températures qui plongent sous les -200 degrés Celsius. À titre de comparaison, la Terre tourne à 150 millions de kilomètres du Soleil.

En avril dernier, Gliese 581e avait été présentée comme la plus petite exoplanète. Les découvreurs de Corot 7b estiment que seule la masse de cette dernière est connue, ce qui n’est pas le cas pour Gliese 581e.

Even though my French Translation class is obviously in the humanities, I was a little surprised at some of the students’ reaction to this article — it clearly was perceived as a bit out of place! However, several people commented on how they learned a lot from it: some didn’t even know that we’d discovered exoplanets (!) and others did additional research, reporting (correctly) that we’ve discovered more than 300 of these bodies! So I guess it turned out to be an unexpected chance to sow a little science, and alert others to one of the most amazing advances we’ve made in the last couple of decades (in my humble opinion).

But without further ado, here is my translation:

The first rocky exoplanet

Nearly 15 years after the discovery of the first exoplanet in 1995, European astrophysicists announced that they have found the very first rocky exoplanet around a star other than our Sun. The exoplanet Corot 7b was observed at the beginning of the year, but its composition could not be established until now. Its composition is not Corot 7b’s only distinction. It is also the smallest ever discovered, with a radius equivalent to 1.8 times that of the Earth. Moreover, it is the planet closest to its own star. It orbits in only 20 hours (corresponding to the length of its year). The HARPS spectrograph installed on the 3.6-meter European telescope at La Silla [an observatory], in Chile, has also established that its mass corresponds to 4.8 times that of the Earth.

Life is impossible
Temperatures exceed 2000 degrees Celsius on the illuminated side, since the planet is located only 2.5 million km from its star. The planet* may have oceans of lava on its surface. The other side, plunged into night, is icy, with temperatures that drop to less than -200 degrees Celsius. For comparison, the Earth orbits at 150 million km from the Sun.

Last April, Gliese 581e was presented as the smallest exoplanet. The discoverers of Corot 7b consider mass to be [definitively] known only for Corot 7b, and not for Gliese 581e.

*The word “astre” is translated as “star”, but that makes no sense here; it should be “planet”.

I must say, that final sentence gave me the most trouble! Suggestions about other ways to phrase it are certainly welcome.

In class, we discussed my translation, and I received several suggestions about ways to improve it:

  • “à ce moment” should have been translated as “at that time” rather than “until now.”
  • Consider “duration of its year” rather than “length of its year.”
  • Consider breaking the final sentence of the first paragraph into two sentences, as it is rather unwieldy.
  • Consider changing “The other side, plunged into night” to simply “The dark side” (for clarity over poetry). I disliked “plunged” myself, because it sounds overly dramatic. If wishing to stick closer to the original, someone else suggested “The other side, immersed in night” (less sense of active motion).
  • Apparently “À titre de comparaison” is a stock phrase that means “By way of comparison,” although “For comparison” also works (is probably less formal, though).

After class, I checked how Babelfish and Google Translate rendered this text into English. The Babelfish version is heart-stoppingly bad, beginning with

“Nearly 15 years after the discovery of the first exoplanète in 1995, of the European astrophysicists announced to have found a very first planet of the rock type around d’ another star that our Sun.”

It’s not terrible that Babelfish doesn’t know the word “exoplanète”, but its inability to handle contractions throughout the article is really inexcusable, especially for French! Google Translate’s version is consistently better, but not perfect. The first sentence is rendered:

“Nearly 15 years after the discovery of the first exoplanet in 1995, the European astrophysicists have announced to have found a first-type rocky planet around a star other than our Sun,”

but it failed to catch the negation in the second:

“The COROT exoplanet 7b was observed earlier this year, but its composition had been established at this time.”

(Also humorous is its translation of “581e” as “581st” — subtle!)

I guess I am encouraged that there’s still a need for human translators!

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