Wednesday, October 9, 2024

61 of 100: Nasa's Europa Clipper mission (and a poem by Ada Limón)

I am stealing wholesale an email I received today, about a project that is fascinating, and that incorporates a beautiful poem. Here's the intro (modestly adjusted by me):

As part of her stint as US poet laureate, Ada Limón wrote “In Praise of Mystery: A Poem for Europa,” dedicated to NASA’s Europa Clipper mission. She debuted the poem on June 1, 2023, to kick off the NASA “Message in a Bottle” campaign, which invited people around the world to sign their names to the poem. The poem has been engraved on the Clipper, along with participants' names that were etched onto microchips mounted on the spacecraft. Together, the poem and names will travel 1.8 billion miles on Europa Clipper’s voyage to the Jupiter system.   

One point eight billion miles, people!

The Clipper is scheduled to launch tomorrow, October 10, at 12:31 p.m., on a SpaceX Falcon Heavy rocket from Launch Complex 39A at NASA's Kennedy Space Center in Florida (assuming Hurricane Milton doesn't interfere). Beyond Earth, Jupiter's moon Europa is considered one of the solar system's most promising potentially habitable environments.

Here is the poem. It moves me to tears, truly. I've included a bit more on the science of the mission at the end of this post.

In Praise of Mystery: A Poem for Europa

by Ada Limón

Arching under the night sky inky
with black expansiveness, we point
to the planets we know, we

pin quick wishes on stars. From earth,
we read the sky as if it is an unerring book
of the universe, expert and evident.

Still, there are mysteries below our sky:
the whale song, the songbird singing
its call in the bough of a wind-shaken tree.

We are creatures of constant awe,
curious at beauty, at leaf and blossom,
at grief and pleasure, sun and shadow.

And it is not darkness that unites us,
not the cold distance of space, but
the offering of water, each drop of rain,

each rivulet, each pulse, each vein.
O second moon, we, too, are made
of water, of vast and beckoning seas.

We, too, are made of wonders, of great
and ordinary loves, of small invisible worlds,
of a need to call out through the dark. 

 

What will Europa Clipper do?

Europa Clipper’s main science goal is to determine whether there are places below the surface of Jupiter’s icy moon Europa that could support life. [Ed.: Jupiter has 95 or more moons, by the way, three of which—Europa, Ganymede, and Callisto—are icy. In April 2023 the European Space Agency launched its own spacecraft, the Jupiter Icy Moons Explorer, or Juice, to study these three, especially the latter two.]

The mission’s three main science objectives are to understand the nature of the ice shell and the ocean beneath it, along with the moon’s composition and geology. The mission’s detailed exploration of Europa will help scientists better understand the astrobiological potential for habitable worlds beyond our planet.

NASA's Europa Clipper spacecraft will perform dozens of close flybys of Jupiter’s moon Europa, gathering detailed measurements to investigate the moon. The spacecraft, in orbit around Jupiter, will make nearly 50 flybys of Europa at closest-approach altitudes as low as 16 miles (25 km) above the surface, soaring over a different location during each flyby to scan nearly the entire moon.

Designed for Jupiter’s tough radiation environment

Because Europa is bathed in radiation trapped in Jupiter's magnetic field, Europa Clipper's payload and other electronics will be enclosed in a thick-walled vault. This strategy of armoring up to go to Jupiter with a radiation vault was developed and successfully used for the first time by NASA’s Juno spacecraft. The vault walls—made of titanium and aluminum—will act as a radiation shield against most of the high-energy atomic particles, dramatically slowing down degradation of the spacecraft's electronics.

Life beyond Earth

Europa shows strong evidence for an ocean of liquid water beneath its icy crust. Beyond Earth, Europa is considered one of the most promising places where we might find currently habitable environments in our solar system. Europa Clipper will determine whether there are places below Europa’s surface that could support life.

The spacecraft's payload will include cameras and spectrometers to produce high-resolution images and composition maps of Europa's surface and thin atmosphere, an ice-penetrating radar to search for subsurface water, and a magnetometer and gravity measurements to unlock clues about its ocean and deep interior. The spacecraft will also carry a thermal instrument to pinpoint locations of warmer ice and perhaps recent eruptions of water, and instruments to measure the composition of tiny particles in the moon's thin atmosphere and surrounding space environment. 


Sunday, October 6, 2024

Book Report: Lonesome Dove

16. Larry McMurtry, Lonesome Dove (1985) (10/5/24)

One day on the way home from doing trail work in the Ventana Wilderness, my companions and I got to talking about books. I'm not sure how Lonesome Dove came up, but the other two had read it and said it was great—maybe even one of the best books they'd ever read. Now, that's a mighty good recommendation. So I ordered it. And then, unusually for me, I picked it up and started to read, almost immediately. (Usually, the 857-page books get shelved and glare at me, making me feel guilty, for years on end.) I did have to put it down briefly for the last book I read, but for the last couple of months I've been immersed in Lonesome Dove. 

And man oh man, what a bookwhat a story—what a cast of characters. It definitely deserved its Pulitzer Prize.

What to say about it, really? The book is basically a road trip on horseback, surrounded by cows. It's a restlessness on the American frontier, a quest to satisfy a dream. One of the two Hat Creek head honchos, Augustus McCrae, is bigger than life (though I cannot picture Robert Duvall playing him in the TV series—for me, he was Sam Elliott all the way; though Duvall could easily be the other head honcho, Call... maybe I will adjust my take once I've seen the series, which I definitely intend to do... as for Tommy Lee Jones as Call, ditto, but again: I'll check it out, maybe it works). Though it does have the grace of a few women's stories as well. And Sheriff July Johnson's story. And the brief appearances of random other characters. So much life!

But it's a sad story. Although it begins in optimism and high spirits, it ends up, well, yes, sad. Sad in the way life can be sad, with its losses and missed opportunities and wrong turns and hardness. There is the satisfaction of actually finishing the drive of the cattle from Texas to Montana near the Canadian border and the establishment of a ranch. And some of the characters find their way to a place of stability and safety, at least, if not necessarily happiness. But there are so many lost opportunities, missed connections. So much loneliness.

I flagged the book like crazy. Here's a passage from chapter 2 (of 102), when the mood was playful and optimistic. The chapter begins by describing Woodrow Call's habit of seeking alone time:

Of course, real scouting skills were superfluous in a place as tame as Lonesome Dove, but Call still liked to get out at night, sniff the breeze and let the country talk. The country talked quiet; one human voice could drown it out, particularly if it was a voice as loud as Augustus McCrae's. Augustus was notorious all over Texas for the strength of his voice. On a still night he could be heard at least a mile, even if he was more or less whispering. Call did his best to get out of range of Augustus's voice so that he could relax and pay attention to other sounds. If nothing else, he might get a clue as to what weather was coming—not that there was much mystery about the weather around Lonesome Dove. If a man looked straight up at the stars he was apt to get dizzy, the night was so clear. Clouds were scarcer than cash money, and cash money was scarce enough. 

And here's a passage from chapter 92, a hundred pages from the end, featuring Gus's true love, Clara—though they were both too independent to be able to come together—and her helping hand, Cholo. Clara's husband has just died, after lying in a sort of coma for three months having been kicked in the head by a horse. And years earlier, she lost three sons to sickness, who continue to haunt her thoughts.

They sat quietly for a while, drinking coffee. Watching Clara, Cholo felt sad. He did not believe she had ever been happy. Always her eyes seemed to be looking for something that wasn't there. She might look pleased for a time, watching her daughters or watching some young horse, but then the rolling would start inside her again and the pleased look would give way to one that was sad.
     "What do you think happens when you die?" she asked, surprising him. Cholo shrugged. He had seen much death, but had not thought much about it. Time enough to think about it when it happened.
     "Not too much," he said. "You're just dead."
     "Maybe it ain't as big a change as we think," Clara said. "Maybe you just stay around near where you lived. Near your family or wherever you was happiest. Only you're just a spirit, and you don't have the troubles the living have."
     A minute later she shook her head, and stood up. "I guess that's silly," she said, and started back to the house.

I've got death on my mind lately anyway, and most of the deaths that happen in this book were, yes, sad—unnecessary, in a way, though of course the only "necessity" about death is that it happen, at some point. Many, or maybe all, of these deaths come from violence, whether natural—a swarming mass of cottonmouth snakes—or human-caused—being gunshot or lanced or arrowshot or hanged. You want to see the bad guys get their dues, but not the good, innocent ones. The ones still trying to figure out, understand, just what they really want from life.

This is apparently the third book in a tetralogy. I'm content to inhabit only this slice of that reality. I don't want to see any more death (McMurtry, in a 2010 preface to LD, indicates that a main character who ends up alive in this book does eventually meet his end, and honestly, I'd rather just remember him alive), and I don't need to experience the Texas Rangering past of Gus and Woodrow. This book gave me an entire world, and I am grateful, if sadly so, for that.