Tag Archives: exobiology

Can versus Should

The topic of directed panspermia found its way into a recent issue of The Economist:  Colonizing the Galaxy is Hard. Why Not Send Bacteria Instead?

The concept, apparently being discussed by “a number of scientists”, involves jump starting evolution on exoplanets by seeding them with terrestrial bacteria.  With human interstellar travel likely centuries away, the proposal is to send tiny probes–containing microscopic passengers–in the near term.  These could be propelled using solar sails and Earth based lasers, along the lines of what is proposed for use in NASA’s Starlight (also known as “DEEP-IN”) program.

The article presents valid objections to this idea, including the worry of contaminating worlds were life might have arisen independently.

However I see a more practical reason for opposing such efforts.    Directed panspermia of this nature is being discussed because it is all we have the potential to do near term.  But technological advances over the next two centuries are likely to expand our capabilities greatly, including the ability to send larger, more capable exploratory craft and perhaps even human crews.  Sending smaller craft now, at best, provides a head start of a couple of centuries on an evolutionary process that is likely to take hundreds of millions or even billions of years to produce anything significant, assuming conditions are ideal.  That hardly seems worth the effort or risk.

When it comes to seeding life in distant solar systems, the sensible thing to do is to wait until we can do it responsibly.  Just because we can do it in the next few years, doesn’t mean we should.

Mars Sample Return on the Cheap?

I recently attended a presentation about the BoldlyGo Institute, hosted by the Rice University Space Institute.  BoldlyGo is a “non-governmental, non-profit organization founded to address highly compelling scientific questions through new approaches to developing space science missions while engaging the global community in the quest.”  As presenters Dr. Laurie Leshin (Worcester Polytechnic President) and Dr. Jon Morse (BoldlyGo CEO) put it, they are trying to fill the science and exploration gap resulting from stagnant NASA funding.

Their first proposed mission, surprisingly, is a Mars sample return mission.  Sound too ambitious?   Maybe not.  I’ve posted about the welcome reset of expectations for Humans-to-Mars, with a shift to focusing on a Mars flyby as the initial near-term goal.   Similarly, BoldlyGo’s SCIM mission (“Sample Collection to Investigate Mars”) is a fresh alternative to the standard sample return missions that have never gotten off the drawing board.

With a baseline launch opportunity in August 2020, SCIM performs a daring high-speed atmospheric pass down to below 40 km altitude timed to coincide with seasonal Martian dust storms, collecting thousands of Martian dust particles from the atmosphere. After the sample collection pass at Mars, the spacecraft returns directly to Earth, where its precious, sterilized samples descend by parachute to the ground.

While the sample size will be small, it is anticipated that the particles collected will be representative of the ubiquitous Martian dust, and that back on Earth the dust can be subject to intense examination not foreseeable on a near-term robotic mission.  For the relatively low price of perhaps $300 million, that’s a lot of scientific bank for the buck.

Before There Was Oxygen

Scientists examining ancient rocks from Western Australia have announced the discovery of fossils of sulfur-loving bacteria from nearly 3.5 billion years ago.  The significance is that there was not much oxygen on Earth back then, and this type of life could have flourished elsewhere in the solar system in the past, or even today.

Tubular microfossils. CREDIT: David Wacey

Readers of In the Shadow of Ares will recognize a clear parallel to an important discovery in the novel.  This is precisely what we had in mind.

Awfully convenient to have human scientists on the ground to know what rocks to examine.   I look forward to the day when we have boots on Mars and can answer some truly provocative questions.

Still, there are plenty of fantastic reasons for going that have nothing to do with science.

Are We Alone?

Dr. Richard B. Hoover of NASA’s Marshall Space Flight Center claims to have found proof of alien life.  In a study published Friday in the Journal of Cosmology, Hoover says that fossils found in a very rare CI1 carbonaceous chondrite meteorite are conclusive evidence of alien bacterial life.

This is hardly the first such claim, and echoes studies involving the Allan Hills 84001 Martian meteorite that have prompted debate that has been ongoing since 1996.  This time NASA came out quickly and indicated that there was no support from other researchers for Hoover’s claims.

Hoover’s study was previously made available for peer review, and those comments are supposed to be published soon, so I’ll withhold judgement for now.  Of course, if you’re interested in how the discovery of living alien microbial life might play out, check out In the Shadow of Ares.

UPDATE:  NASA Watch questions several aspects of Richard Hoover and his paper, including whether or not he is a doctor of anything.  Oops.

Life Imitates Art: Portable DNA Sequencers

FuturePundit points to a NYT article describing something very similar to a piece of technology readers might recognize from the Oasis scene of In the Shadow of AresTaking DNA Sequencing to the Masses:

Dr. Rothberg is the founder of Ion Torrent, which last month began selling a sequencer it calls the Personal Genome Machine. While most sequencers cost hundreds of thousands of dollars and are at least the size of small refrigerators, this machine sells for just under $50,000 and is the size of a largish desktop printer.

While not intended for the general public, the machine could expand the use of DNA sequencing from specialized centers to smaller university and industrial labs, and into hospitals and doctors’ offices, helping make DNA sequencing a standard part of medical practice…

Rather than culturing a bug to identify what is infecting a patient, for instance, a hospital might determine its DNA sequence. Massachusetts General Hospital is already sequencing 130 genes from patient tumor samples, looking for mutations that might predict which drugs will work best. It has won an Ion Torrent machine in a contest and hopes to put it to that use…

While most experts agree that sequencing will become commonplace in medicine, some say they think Dr. Rothberg is overselling his machine. Like the early Apple II of Mr. Jobs, it is too puny for many tasks, including sequencing the entire genome of a person…

Dr. Rothberg acknowledged that the existing model was good for sequencing a virus or bacterium or a handful of genes, and indicated that future models would be more powerful.

Indeed. Just imagine what forty more years of technological evolution might do to this device, in terms of cost, power, speed, and size.