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Do you ever miss the 70s?  That time will never return (although stagflation and oil crunches might make an unexpected comeback from the weird devil’s brew of bad economic and geopolitical policies which we are experimenting with) however there is a more positive reminder of the age of disco in the very heavens themselves.  At present, there are three disco balls in orbit around Earth.  The first and most significant is actually a 70s artifact: LAGEOS (Laser Geodynamics Satellite) was launched from Vandenberg Air Force Base on May 4th 1976.  The 408 kilogram (900 pound) satellite has no electronic components ore even moving parts: it is a brass sphere studded with 426 jewel-like retroreflectors. 422 of these retroreflectors are made from fused silica glass (to reflect visible light), however the remaining 4 are germanium, for infrared experiments.

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Orbiting the entire planet every 225.70 minutes, LAGEOSl is a pretty stupendous piece of space art in its own right, however it was designed for a serious scientific purpose.  Lageos provides an orbiting laser ranging benchmark.  To quote space.com:

Over the past 40 years, NASA has used LAGEOS to measure the movement of Earth’s tectonic plates, detect irregularities in the rotation of the planet, weigh the Earth and track small shifts in its center of mass via tiny changes in the satellite’s orbit and distance from Earth.

Measurements made using LAGEOS have also been used to confirm Einstein’s general theory of relativity, since measurements made on this scale demonstrate a measurable “frame dragging effect” (which you are going to have to figure out with some help from your favorite physicist).  The satellite also illustrates the Yarkovsky effect, which explains how an object is heated by photons on one side will later emit that heat in a way which slows the object.  This latter effect will eventually cause LAGEOS’ orbit to deteriorate and bring it tumbling to Earth.  Scientists estimate this will happen 8.4 million years from now, so there is still time to contemplate this sphere.  Also there is a small time capsule on board to capture certain scientific truths and human ephemera for the long ages.

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LAGEOS was so useful and proved to be such a success that NASA launched an identical sister craft in 1992 (how did I miss all of these interesting events?).  This still leaves one disco ball satellite unaccounted for.  The final craft is “The Humanity Star” which serves no purpose other than being art.   Launched on January 21st of this year (2018), the humanity star is a regular polygonal solid with 65 triangular sides.  It is made of carbon fiber embedded with enormously reflective panels and is meant to be seen twinkling in the night sky to make humankind collectively reflect on our shared home, the Earth.  The Humanity Star orbits much lower than the LAGEOS satellites.  They are  5,900 kilometres (3,700 miles) from Earth’s surface, whereas the humanity star is only 283.4 kilometers (176.1 miles) away from the planet at its perigree.  It whips around the Earth every 90 minutes on a circumpolar orbit (which means it is visible from everywhere at some point.  You could look up where it is online and go out and find it with fieldglasses.  The object glimmers and shimmers in unusual ways, sometimes appearing as bright as Sirius (the brightest star save for the sun), but usually twinkling like barely visible stars.  The Humanity Star won’t last long—it is scheduled to fall into Earth’s gravity well and burn up in fall of this year, so check it out before it is gone.  The craft was controversial: some serious aerospace mavens objected to launching an object into orbit to serve no purpose other than art, yet, as an artist I am happy to know it is out there.  Maybe go look at it and let me know if it inspires you.

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Many people complain that the news is all bad.  That is not true at all, but good news is sometimes harder to quantify or follow than bad tidings—plus human progress tends to be incremental.  I bring this up because this week did feature a good news story—and Ferrebeekeeper has been following along (as best we can) for years. The nuclear scientists at the National Ignition Facility (a part of Lawrence Livermore National Laboratory) have been attempting to use a vast laser array to heat/compress a deuterium and tritium fuel pellet to the extreme conditions necessary for nuclear fusion.

The container for the nuclear fuel

The container for the nuclear fuel

Nuclear fusion involves compressing/heating the elementary particles which make up atoms until the atoms fuse into new atoms.  Such a process releases outrageous amounts of energy but it does not start easily–indeed so much energy is required to begin the reaction that “hot” fusion typically requires a star or a nuclear fission detonator.  These items are dangerous and alarming to have lying around so scientists have been attempting to find a more controlled method of fusing atoms together.

The NIF Target Chamber

The NIF Target Chamber

Earlier this week the science journal Nature published a paper which details how NIF scientists finally managed to produce more energy than was initially put into the fuel pellet (albeit not into the overall system).  This does not sound overwhelmingly exciting—yet it is farther than nuclear engineers have got in 50 years.  To quote the amazingly named head scientist, Omar Hurricane, “We’ve assembled that stick of dynamite and we’ve gotten the fuse to light…If we can get that fuse to burn all the way to the dynamite, it’s going to pack a wallop.”

Just dream what we could accomplish with such energy!

Just dream what we could accomplish with such energy!

Abundant safe energy from nuclear fusion would be an astonishingly transformative innovation for humankind.  Immediately our principle economic and environmental problems would be forever altered.  Additionally having such a cosmic wellspring of energy available would allow us to embark on engineering works of a vastly greater scale than any known so far.

Planetary Engineering!

Planetary Engineering!

So, it is not easy to do what has never been done before. In October of 2010, I wrote about the National Ignition Facility, a joint scientific project run by Lawrence Livermore National Laboratory in Livermore California.  The National Ignition Facility aims to recreate the heat and pressure of stars and hydrogen bombs on a microscopic controlled scale.   The project is ostensibly designed as a United States defense project to model the nation’s next generation nuclear arsenal without use of (treaty-prohibited) nuclear testing, but cognoscenti have long suspected that it is a way that our country can pursue fundamental energy and physics research despite the apathy (or outright animosity) of a do-nothing congress and politically divided citizenry.

One of four banks of giant capacitors which power the laser microburst

Unfortunately the facility experienced a series of setbacks, and the massive laser array did not deliver the promised energy output.  However, this month all that changed!  On July 5th the facility briefly powered up its 192 lasers to deliver a 1.85-megajoule blast that released more than 500 trillion watts of power. Although the laser beam was only active for a miniscule fraction of a second, during that brief time it was focusing a thousand times more energy than the rest of the entire United States was actively using.  Remember Doc Brown from “Back to the Future” shouting about “1.21 gigawatts!” and desperately running his hands through his hair? Well, a gigawatt is a billion watts.  This laser beam produced a 500 terrawatt blast–500 trillion watts.  So just imagine Doc shouting “1.21 gigawatts!” four hundred thousand plus times!

The successful test firing brings the NIF within tantalizing reach of their desired ignition breakthrough—the glorious moment when scientists flip a switch and create a controlled, contained fusion reaction.  Building such a “star in a jar” is the first step on a road to titanic engineering and energy-creation achievements which could reshape humanity’s place in the universe.

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