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Space Flounder.jpg

I am still working away at my flatfish project.  Here are four recent drawings/mixed media works which I made.  The flounder above is a cosmic flounder and represents humankind’s aspirations for the stars.  The mathematicians and engineers (here represented as ancient Egyptians) do their best with the tools and calculations they have available, but the universe is so vast.  The flounder represents all Earth life waiting to be lifted to the heavens.  As they struggle, insouciant aliens fly by waving.  The combination of ancient and modern elements make one think of the biblical ark (which is represented in the next picture. The flounder is, of course, a watery beast and is unmoved by divine wrath, although it does look a bit appalled at the inundation.

ark

Next is a picture of a crude and vigorous flatfish made out of thick lines.  The fish swims by a Viking long hall as seabirds wheel about in the sky, but thanks to some trick of the world (or perhaps the artist’s whimsy) a coati is raiding the pumpkins and fruiting vines. Is this scene unfolding in the old world or the new?

coati

Finally, there is a scene of a medieval styleeremitic  brother who has forgotten his scriptures and is now contemplating the life-giving sun.   A saintly duck and a far-flying swallow look kindly on his devotions, but the monk’s cat seems unmoved by his devotion.  Crystals hint that religious fervor is becoming convoluted by the vagaries and appetites of the modern world, which can be witnessed all around the verdant turbot.  Yet the fish and its inhabitants maintain a solemn and studious otherworldliness.  Whatever this mysterious devotion is, it is represented in each of these 4 fish, but the viewer will have to devote some time and thought of their own in order to elucidate the subject of this devout zeal. 

monastic

An artist's rendition of NASA's MESSENGER spacecraft

Yesterday NASA’s spacecraft MESSENGER entered orbit around Mercury, the least explored of the Solar system’s rocky inner planets.  This is the first time a spacecraft has been in orbit around Mercury and it represents a tremendous engineering achievement. Since gravity becomes more intense the closer one comes to the sun, Messenger had to slingshot back and forth among the inner planets for some time in order to accomplish the tricky feat. The spacecraft had to undertake a 4.9 billion mile (about 7.9-billion kilometer) journey to enter orbit around the closest planet to the sun. Of course that hefty mileage only is equal to 0.00083 light years!

Having survived the grueling trip, the spaceship must now carry out its mission in the blistering bath of solar radiation.  To survive next to the star, Messenger is equipped with a large sun visor which prevents the little craft from frying like a quail egg.

NO! The Messenger spacecraft is not an old lady playing golf!

Messenger will try to determine the planet’s mineralogical composition and learn about its geological history (the surface of Mercury is reckoned to be one of the oldest in the solar system).  The robot probe will fully map Mercury and analyze the planet’s composition.  Like Earth (but unlike Mars and Venus) Mercury has an internal magnetic field.  Additionally, the tiny world is incredibly dense. In order to learn more about the planet’s core Messenger will measure the extent to which the planet wobbles on its rotational axis.  Studying the partially molten interior of Mercury should provide clues about how the planet formed which will help us better understand the creation of all planets (especially in conjunction with the flood of data regarding exoplanets which we are beginning to receive).

Since the craft will be trying to learn the secrets of Mercury’s molten interior, it is worth reflecting on the deity whom the planet is named after.   Although he was worshipped as a messenger, a herald, and a god of commerce, the Greco Roman god Hermes/Mercury was also quietly worshipped as a god of the underworld. The Greeks and Romans regarded him as a psychopomp who guided souls down to Hades with his magical staff. Because (like the somewhat similar African traveling god Eshu) Hermes was able to go anywhere at will he was one of the only entities in the Greco Roman pantheon free to enter and leave the underworld.

Although we are not capable like Mercury of going everywhere at our whim, I think it is a tremendous accomplishment to navigate a robot spacecraft into broiling orbit around the innermost planet.  That we are using the craft to learn the secrets of the fiery underworld of the swift planet seems like a fitting tribute to the god who was slayer of Argus, giver of charms, messenger, schemer, luck bringer, and patron of travelers and wayfarers (even those voyaging to their last end or to places the ancients could never dream of).

Electromagnetic radiation exerts pressure on physical matter.  The more the radiation is reflected from the surface it strikes, the greater the pressure–so sunlight presses harder on a mirror than on, say, an ostrich with the same surface area.  I’m not going to dwell on the physics underlying this fact (although I will provide a link), but rather on the remarkable ramifications.  Contingent on the amount of radiation, this force is rather weak. However, taken in aggregate, across a large surface, light (or any form of EM radiation) can move an object.  Hence…solar sails!

IKAROS (image from JAXA)Much in the manner that wind pushes a sailboat through water, light can push an object through space. Although using such a sail for space travel was demonstrated to be feasible in the laboratory, the great national space programs—NASA, Russia, ESA, and China—have never successfully tested a solar sail in interplanetary space (despite several failed attempts). However, this year on May 21st the Japan Aerospace Exploration Agency (JAXA) successfully launched the IKAROS solar sail.  IKAROS stands for “Interplanetary Kite-craft Accelerated by Radiation Of the Sun”–an acronym which somehow is both unwieldy and an allusion to a badly botched aerospace venture (JAXA can be forgiven for the awkward name however thanks to the success of the mission). IKAROS is a square sail with a diagonal diameter of 20 meters.  It is made of polymer 7.5-micrometres thick.  A solar array is embedded in the sail to supply the craft’s power needs.  To provide attitude control, the sail also contains LCD panels with adjustable reflectivity.  Various sensors, dust counters and controls are located on different parts of the craft.

IKAROS Mission Plan (JAXA)

IKAROS deployed its sails when it was approximately 4.8 million miles from Earth (smoothly deploying a delicate lattice of sails in the grim void of outer space has been a major obstacle to this sort of mission in the past). The spacecraft is currently somewhere between Earth and Venus.  When it reaches the cloud planet, it will embark on a three year trip around the sun.

To follow up its success JAXA is planning to launce a 50 meter solar sail to the asteroid belt and Jupiter sometime late in the decade.  Other space agencies have taken note and are now playing catch-up with the Japanese.  NASA has plans for several solar sail missions in the coming years (provided poor national leadership does not botch the plans or scrub the funding). Since rocket fuel is heavy (and therefore a major sorce of missin costs), solar sailing technology has interested space agencies and space exploration enthusiasts for some time.  The Planetary Society, an international group dedicated to space exploration, has long advocated solar sails as a revolutionary step forward in space travel. In fact, the Planetary Society chartered a submarine launched Russian rocket to deploy its own solar sail into space but the mission sadly failed when the rocket malfunctioned.  Fortunately, the society has regained its old maniacal chutzpah and is launching a new solar sail mission (additionally, and even more importantly, it continues to lobby national governments for additional space funding)  

JAXA's next solar sail mission will apparently look like throwing a shuriken into an asteroid. Awesome!

In the near future, solar sails might be used for interplanetary missions or for de-orbiting old satellites and space debris (this latter task is growing in importance as humankind fills up near earth orbit with junk).  Hybrid drives which utilize solar sails and solar powered ion drives in tandem are also on the drawing board. In the farther future, who knows?  So far this is the only possible option for interstellar travel which utilizes technology humankind currently possesses (well, aside from ridiculous nuclear fission designs).  It has been proposed that giant space lasers could be used in tandem with the sun to accelerate probes to nearby stars.  Unfortunately such lofty prospects are still science fiction at present.

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