Life Held Home

On February 22, 2017, all eyes turned to TRAPPIST-1.

And then squinted a lot. Because this star, you can’t see it. It likes about 40 light years away in the constellation Aquarius.

The water-bearer. Remember that.

Because orbiting TRAPPIST-1, NASA has identified 7 planets, three of which may be warm enough to be home to liquid water.

The planets orbit in a tight group around their star, all well within a circle representing the orbit of the planet Mercury, in a clumpy, resonant configuration similar to that of the Galilean moons of Jupiter.

And I’m not surprised at all.

And worlds without number have I created; and I also created them for mine own purpose; and by the Son I created them, which is mine Only Begotten.

Moses 1:33

We know there are worlds out there. That some have been found is exciting. But not surprising.

And yet so distant.

Who can visit them? No one, not form our solar system. Not with our present technology, not with our present lifespans. We haven’t been back to Earth’s own Moon for more than 50 years, and it lies a mere 248,000 miles away. The fastest objects ever created – the Voyager and Pioneer Probes, along with New Horizons – are barely beyond the orbit of Pluto, or barely beyond the shock wave that marks the beginning of interstellar space.

We are no closer to these planets than were our ancestors, starting up at the lights in the sky and watching them dance.

And it does not make me melancholy. Because they are not ours to have.

Nor are our planets for others, perhaps looking up at our distant star, much bigger than theirs. They may imagine life in a hostile solar system, where the light and energy put out by our star is so much more intense than theirs. Maybe they look at that third, possibly the fourth planet, as places where water and life may exist.

But they, too, never will visit. All life is held home by the vastness of the spaces between the stars.

An Eclipse on Mars

So. Something else for the Hermit of Iapetus to see, ponder, get freaked out by.

Dare Mighty Things

The Hermit of Iapetus is going to have to know this kind of stuff. He's going to have to know how to dare mighty things, and completely on his own as well, because there's no one there to help him out if he gets stuck.

. . . Only the Planets Are Big

This NASA photo is in the public domain. The large white-rayed crater is Debussy. Note to the west another crater, with much smaller black rays.

Space is small; only the planets are big.

Robert Kleinman, fictional spacefarer in Arthur C. Clarke’s “Imperial Earth”

I think Robert Kleinman would agree that Mercury is looking pretty big.

This is, of course, the first photo taken of Mercury from NASA’s Messenger probe, which entered orbit of the planet on March 17.

Why is this exciting? Well, I’ve been caught up with NASA’s exploration of our solar system since the days of Pioneer 11 when I was a kid. I used to draw elaborate charts of the paths of Pioneer and the Voyager spacecrafts, indicating how old I would be when the probes reached the outer planets.

I was a geek, yessir.

Still am. I’m still convinced I’ll be able to walk on the moon as a space tourist before I die. How that will happen, I don’t know. But I maintain faith it will, even if I have to get an old space suit, a lawn chair, some scuba gear and an awful lot of helium-filled weather balloons.

Arsenic-Based Life? Just Add Water.

Barely a week after announcing the discovery of a bacteria from California’s Mono Lake a group of NASA-funded and –associated scientists insist incorporate arsenic compounds, rather than phosphorous compounds, into their DNA and other cell structures – thus broadening our view of conditions conducive to life – others in the field are shaking their fingers at the science.

Read it here at Slate.com.

To sum up: The scientists Slate spoke to don’t deny that arsenic-based life could exist, they merely challenge what they call sloppy methodology in the NASA experiments that don’t take into account that arsenic is much more prone than phosphorous to dissolve in water – leaving arsenic-based DNA in tatters, rather than the chunks the scientists identified – along with the fact that some of the salts fed to the bacteria were “contaminated” with phosphorous, thus not eliminating the possibility that the bugs merely “eked out” an existence on the available phosphorous rather than substituting the arsenic.

I don’t pretend to understand the intricacies of the science, but I’ve always loved a good flim-flam story, especially when those accused of the flim-flammery retreat rather than address the criticism. Rosie Redfield, a microbiology researcher at the University of British Columbia and one of the experts quoted by Slate does what I assume is an admirable job of taking apart NASA’s research here. Another explanation of the phosphorous/arsenic in water trick can be found here, written by Harvard microbiologist Alex Bradley (I found this one a bit more accessible to my layman brain).

What I appreciate about the approach the critics are taking is that they’re not saying, “Oh no. Arsenic-based life can’ exist.” Because they’re scientists, they want to look at the evidence before they reach any conclusions. What they are saying is that the methodology used in the NASA paper doesn’t prove that these Mono Lake bacteria are arsenic-based life forms. Bradley sums it up pretty well by saying that even in the absence of esoteric biochemical processes which could keep arsenic-based DNA from dissolving in water:

In the absence of biochemistry, pure chemistry takes over: any arsenate-DNA would have been quickly hydrolyzed in the water, breaking down into fragments of small size. Alternatively, phosphate-DNA would not hydrolyze quickly, and large-sized fragments might be recoverable.

Slate’s story is worth reading for the explanation of the science, as well as to see how quick some scientists are to announce Earth-shattering news and then equally as quick to hide behind peer-review procedurals when their science is called into question. Carl Zimmer, writing for slate, quotes Jonathan Eisen of UC-Davis as saying:

If they say they will not address the responses except in journals, that is absurd. They carried out science by press release and press conference. Whether they were right or not in their claims, they are now hypocritical if they say that the only response should be in the scientific literature.

It does seem odd to me to use the penny press to announce your news, then scurry behind the peer-review structure when the critics come out – and you knew the critics would come. So I’ll be watching this with much interest.

Arsenic-Munching Bugs

Photo courtesy NASA

So it’s bacteria that metabolize poison.

And not on Mars, Rhea, or Titan, but teeming – some of them with tentacles so they can teem more efficiently – in California’s Mono Lake.

What’s significant is that this is more than bacteria using arsenic compounds instead of water in photosynthesis, this is bacteria using arsenic rather than phosphorous to build themselves.

Phosphorous, per Science Daily, is one of the building blocks of DNA and RNA. Arsenic, which is chemically similar to phosphate, is toxic to some life forms because it takes the place of phosphorous. Apparently, these bacteria have learned to adapt to that substitution.

Sez Science Daily:

“The idea of alternative biochemistries for life is common in science fiction,” said Carl Pilcher, director of the NASA Astrobiology Institute at the agency's Ames Research Center in Moffett Field, Calif. “Until now a life form using arsenic as a building block was only theoretical, but now we know such life exists in Mono Lake.”

Plenty damn cool. Kinda Andromeda Strain cool and creepy as well, and certainly fodder for new science fiction stories waiting to be written: They came! They farted! We all died of arsenic poisoning!

Now scientists can consider celestial bodies where arsenic is plentiful as potential cradles of life, not necessarily clouds of doom for life. What Jeff Goldblum’s character in Jurassic park says, indeed, is true: Life finds a way.

And why is that really shocking? Frankly, I expect there to be life on other worlds. In this infinite universe of ours, our puny planet – and our incomplete understanding of the conditions conducive to life – cant’ be the summum bonum of all that’s out there. It’s nice to know that we’ve got a different set of conditions to consider.

For Fear of Little Men

This photo is in the public domain.

I’m looking forward to NASA’s “astrobiology” press conference tomorrow.

Not that I’m expecting them to announce the discovery of little green men. Or the discovery of life in any way, shape, or form. Given the skepticism and cautions that abound in the full spectrum that surrounds the search for extraterrestrial life, I don’t expect them to make such an announcement without having ET or some esoteric plant to show off as well.

What I do expect is that they’ll announce the discovery of arsenate and arsenite compounds on either Mars or either of Saturn’s moons Rhea or Titan. This is exciting not only because it gives Agatha Christiesque murder mystery writers a truly unique murder weapon, but because of recent discoveries on Earth of bacteria that use arsenite rather than water in the photosynthetic process.

In other words, they won’t announce the discovery of life, but the possibility that conditions conducive for some type of life as we understand it on Earth exists elsewhere in the solar system.

Or, perhaps, they’ll announce that at “9 am, Eastern Standard Time, the United Nations Building – whissssh – will vanish. Hahahahahah.” But that’s a bit too Dreyfussesque, isn’t it?