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Wednesday, February 4, 2015

A BETTER WAY TO SEARCH FOR EXTRASOLAR PLANETS

Forty three years ago I used a tunable dye laser to catalyze/sterilize E. coli for my PhD Dissertation.  Three years later I worked for the NASA Ames Research Center on a project to design instruments to detect extrasolar planets.

Unfortunately, they had only a microwave interferometer in mind and passed on a concept I had advanced with Charles Townes (left, with his maser, and  right, my tunable laser) of the University of California at Berkeley to use the optical spectrum to not only find planets around other starts, but, as importantly, determine the atmospheric composition.  I again bring this subject up because last week Charles Townes passed away, and, coincidentally, a University of Hawaii researcher reported the day following that he had found three earth-like planets.  You will better understand my exasperation about this field after I provide some details.

This will be one of my more arcane and scientific postings ever, but I feel compelled to first point out that NASA astrophysicists and their kind are realistic about funding and their mission.  They feel uncomfortable and avoid any relationship with the looney tunes associated with flying saucers.  Similarly, their budgets are tiny, and the notion of trillion dollar Man on Mars efforts are beyond the pale.  Thus, while Carl Sagan's CONTACT (this is the entire 4 hr 39 minute audio book read by Jodie Foster) might be supportable, anything like Instellar and Star Wars are equally unrealistic, for while, yes, there are possible wormholes and so forth, the energy and technology required are beyond comprehension.

In some ways I was there at the beginning of the search for extrasolar planets (let me just called this SFEP) in the early 1970's.  Of course the modern search for extraterrestrial intelligence (SETI) began earlier in 1959 with the paper by Philip Morrison (right) and Giuseppe Cocconi, suggesting the microwave spectrum where signals might well be coming in from advanced civilians.  Cornell's Frank Drake actually performed Project Ozma (from Wizard of Oz--the field tends to get fanciful) in 1960 using a radio telescope in West Virginia to examine Tau Ceti and Epsilon Eridani, selecting 1.420 gigahertz as the frequency of opportunity, known as the water  hole, near where the hydrogen and hydroxyl  radicals have spectral lines (hint:  hydrogen plus hydroxyl equal water).  Of course he failed, but that is an entirely different pathway to actually doing something real.

Drake's (left) contention in those days was that it will be difficult to convince anyone to spend any money on SETI if our solar system had the only planets in the Universe.  So we needed to find a planet, call it an exoplanet or extrasolar planet, orbiting around any star somewhere in outer space.  Thus, NASA brought to the Ames Research Center in the Summer of 1976 20 faculty members from across the nation to design that first instrument to find that potential exoplanet.
For the reason that this group was headed by Jack Billingham and Barney Oliver (above in later life), who had previously run Project Cyclops, our team was commanded to design a microwave interferometer, which I didn't think was the ideal "telescope" for this particular application.  So they allowed me to find another option.  It was a grand summer of living in a Stanford married student apartment across the street from my freshman dormitory, golfing at the Palo Alto Muni, taking a wine-tasting course at night, watching the 1976 Olympics emanating from Montreal and, by the way, traipsing around northern California collecting info and talking to experts about an innovative way to find the first extrasolar planet.

I had just read a Science article by Charles Townes that planetary atmospheres lased.  He was already a hero of mine for he had won a Nobel Prize in 1964 and with his brother in law, Arthur Schawlow, who had come to Stanford University when I was junior there, had invented the laser, the instrument I used to conduct my PhD research.  So off I drove to Berkeley to meet with Professor Townes, who concurred with me that it might be possible to track the specific wavelengths of lasing extrasolar planets--we should be able to track planets circling stars at various discrete frequencies dependent on the atmospheric composition--thus also determining the life quality potential.  He said he would work with me on this project.  This a photo of Townes (above on the left) and Schawlow latter in life.  Alas, NASA ignored all our proposals, with a statement that the Hubble Telescope would soon fly to accomplish this task.

However, it took another 14 years for the Hubble to attain orbit in 1990 and the first confirmation of an extrasolar planet did not come until 1992.  But what confounds me is that NASA took a brute force technic called transit.  There are various ways to do this, some a lot more elegant.  All the Hubble did was watch stars that changed light intensity because a planet was reducing the light on passage across the star.  That's it.  The good news is that it has probably three more years of life yet.  While you keep seeing a tab of $1.5 billion, $10 billion is closer to the truth as the money spent on Hubble.

Even worse, in my mind, is that the replacement, the Kepler Telescope, only costing $600 million, which became operational in 2009, also used transit, a clearly obsolete technique.  Kepler lost its second gear in May of 2013, but some ingenious effort by scientists from the Ames Research Center has allowed the spacecraft to function for a short while longer.   I hate to say even worse, but the next telescope, the Transiting Exoplanet Survey Satellite, said to be a 2017 launch, will also use transit, but at least will only cost of $200 million.  Feel free to multiply that figure by any number from two to ten.  

But, ah, then, the biggie in 2018, the $8.9 billion (no, make that $10 billion+, for expenses reached $8.8 billion two years agoJames Webb Space Telescope with also a special spectrometer that should be able to analyze planetary atmospheres.  You know, this sounds suspiciously like the Townes-Takahashi Planetary Abstracting Trinterferometer.  But ah, no, because the Webb will only be able to do this for Jupiter-sized planets.  Then why bother???  And that cost was estimated in 2011.

The progress of SFEP:


Have you been counting the dollars?  Don't think NASA has been sleeping, for there are on drawing boards WFIRST, SALSO, OpTIIX and more.  Read the article.  These are mere billion dollar projects, but the James Webb only had a cost of $2.6 billion in 2009 and has jumped to past $10 billion today.  Hubble?  Original cost, $400 million.  Today? $10 billion.


Thus far, from zero in 1976 to zero in 1991 to perhaps 2000 exoplanet confirmations today, there must be ten times that number in the process being identified.  But NASA missed the point.  Frank Drake just wanted one to justify funding for SETI.  Sure, we need be more certain about where to look in the future for Earth-sized potential, but some reasonable logic can be used to argue that there must be intelligent life out there, many far more sophisticated than ours, having had a several billion year head start.


Above are the types of stars being explored.  While we are small compared to the really large ones, our Sun is, actually, brighter than 95% of all the stars.  Those M-types, the smallest, less than half our mass, make up 75% of all the stars up there.

So, to summarize, there are 100 octillion stars in our Universe, that's one followed by 29 zeros, and, perhaps 1 with 24 zeros planets. Something wrong with the logic here, for that means only one planet per 10,000 stars, but these come from two points of view.  Anyway, that's a whole lot of space, so let us for now limit our search just to our Milky Way Galaxy--remember, light takes 100,000 years just to cross from one end to the other--where one estimate is that we have about ten trillion planets.  Could Earth have been the only planet to gain intelligent life?

Which leads me to the article mentioned in the first paragraph about UH astronomer Andrew Howard, quoted to have discovered:

Three Earth-size planets — one possibly with liquid water on its surface — have been found around a distant star with help from the Keck Observatory on Mauna Kea.

What great astrophysics right?  Well, the science used to suggest water was an observance that one of these three is 1.5 the size of Earth, and occupies the so-called "Goldilocks Zone," where water could exist.  Did they detect water?  Nope, the star, EPIC 201, is 150 light years away.  This means that if there is life there, and we make contact, each call will involve a 300 year + wait.  Three hundred years ago was 1715.  George Washington, our first president, was not born until 1732,  The transit technique of course only provides the rough size and location of an extrasolar planet, not the atmosphere.  But the jaded would remark, so what, Planet Earth did it already.

The odds are overwhelming that gazillions of exoplanets have the potential for life-supporting ecosystems.  And many of them could be at least 8 billion years older than us.  Let's get on with capturing extraterrestrial intelligence messages.  Simple step one:  remove the congressional language preventing NASA from doing any SETI work.  Simple step two:  give a billion dollars a year each to NASA and the SETI Institute to re-initiate the effort suggested in CONTACT.


In a decade--after expending $20 billion, less than what has thus far been consumed with current-transit-connected telescopic attempts--review the reality of SETI.  If the weight of science leans in the direction of the Fermi Paradox or the Proxmire Golden Fleece Award, than abandon the effort for another century or millennium.  While the visions of an Encyclopedia Galactica streaming past Planet Earth to provide magical solutions for our needs are enticing, it is possible that we are the only semi-intelligent life in our Universe.

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