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What with all of the excitement in the world, it is easy to lose sight of the bigger picture…and of good things which are still happening during these troubled times. This morning at 7:50 a.m. EDT, NASA launched an Atlas V-541 rocket from Cape Canaveral Space Launch Complex 41. On board the rocket is a Martian lander containing the most sophisticated Martian rover yet “Perseverance” along with its robotic helicopter sidekick “Ingenuity.”
Artist’s Conception of Perseverance and Ingenuity on Mars
If the mission continues to go according to plan, the lander will reach Mars in February 2021. Coincidentally, Mars will be crowded that month, since a Chinese orbiter & lander, and a UAE orbiter are also slated to arrive. After much trial-and-error, I have faith in NASA’s sky crane landing system but it will be most interesting to see if the Chinese rover can “stick the landing”or if it is eaten by the ghosts of Mars (I hope not: humankind needs the Chinese data too, and NASA needs some competition to keep the creative juices and the congressional funding flowing).
The ultimate destination of the Mars 2020 mission is the Jezero Crater, a nearly circular crater 49 km (30 miles) in diameter. The ancient crater is now partially filled with sediments–including a fan delta of ancient clays. It is believed that if evidence of ancient life is to be found anywhere on Mars this is as likely a place as any to discover the ancient fossils.
Jezero Crater
Perseverance has onboard a 4.8 kilograms (11 lb) pellet of plutonium dioxide which will provide the vehicle (and the miniature helicopter) with abundant energy for traveling, communicating with orbiters/Earth, assaying rocks, and operating a core drill for gathering geological samples of ancient Martian rock. Additionally the rover will conduct material experiments concerning the potential toxicity of Martian dust and the production of pure oxygen from Martian atmospheric CO2. Perhaps most excitingly, the rover will also carefully organize and cache the precious samples it gathers in preparation for a future retrieval mission. Such a mission would involve landing, building and launching a Mars ascent vehicle from the Martian surface up to our proposed next generation Mars orbiter which would then load the samples on am Earthbound craft. So the Mars 2020 mission is a tremendous step towards discovering whether life ever gained a toehold on Mars AND towards building next-generation space faring capabilities (for the dull and incurious earthcentric crowd that always decries space exploration–as though Earth is located somewhere other than space!– it should be noted that such engineering breakthroughs generally confer military, technological, and economic supremacy here).
Also, special thanks to our brilliant Norwegian, Spanish, French, and Italian friends!
So best wishes for the entire armada which has left our planet this month headed for Mars, but particular good wishes to Perseverance and Ingenuity! Let’s hope we can discover some perveverance here to make it all the way to February 2021 (right now that sounds like it might as well be some HG Wells date in the impossible future).
In 2016 the Japanese Space Agency launched a quarter-of-a-billion dollar x-ray observatory named Hitomi into Earth orbit. The craft’s mission was to study extremely energetic processes at the far reaches of the universe. It was hoped that the data Hitomi provided would allow astronomers to understand how the large scale structures of the universe came into being (how galactic superclusters form, for example). The satellite initially worked perfectly, but, within 38 Earth days, the spacecraft was lost: a failure of attitude control sent it into an uncontrolled spin which caused critical structural elements to break apart.
The full story of what destroyed Hitomi is perhaps of greater immediate interest to living beings on Earth than how the meta-structures the universe came into being. When everything went wrong for the ill-fated space observatory it was passing over the southern part of the Atlantic ocean. For spacefarers, this region of the Van Allen Belt is analogous to what the Bermuda Triangle or the Namib Skeleton Coast is for sailors: it is a haunted and dangerous stretch of space. Astronauts who travel through it report strange phantasmagorical dots and streaks in their vision, even when they close their eyes. The Hubble Space Telescope does not make observations when it passes over the south Atlantic. Controllers turn off its delicate systems. The region is known to the world’s space agencies as “the South Atlantic Anomaly.” Hitomi was not its first victim–it is surmised that the South Atlantic Anomaly was responsible for the failures of the Globalstar network satellites way back in aught seven.
The existence of the South Atlantic Anomaly was known long before that. It was discovered in 1958 by Explorer 1, the first American satellite (which was equipped with a Geiger counter). Perhaps the Soviets would have discovered the anomaly by means of Sputnik, but, because the Cold War made scientific cooperation difficult, Australia did not hand over Sputnik data to the Soviets until later. Suffice to say, the South Atlantic Anomaly is an anomaly in the Van Allen Belt, the torus-shaped field of charged particles which are held in place by the magnetic field of Earth. Earth’s magnetosphere is important. Billions of years ago, Mars and Venus seem to have been exceedingly Earthlike, with water oceans and convivial atmospheres. But neither Mars nor Venus has a magnetosphere and their oceans have perished and their atmospheres have changed into monstrous things….although we don’t know exactly what happened on either of our neighboring planets (and the present priorities here on Earth are to make Michel Dell and Howard Schultz as rich as possible at everyone else’s expense, not, you know, to understand what planetary scale forces could make worlds uninhabitable).
Um, at any rate, the magnetic field of Earth is created by the mysterious processes beneath our feet at the center of the planet. The Earth’s inner core is believed to have two layers: an outer core of molten iron and heavy metals and an inner core of solid iron nickel alloy. The inner core is about 70% of the volume of the moon and it is nearly as hot as the surface of the sun with an estimated temperature of (5,430 °C) or 9806 °F, but the molten outer core is only as hot as the surface of an orange star (2,730–4,230 °C; 4,940–7,640 °F). Within the outer core, eddy currents form in the superheated metal. The complex relationship between these currents, the spinning planet, and the two core layers creates a geodynamo which produces the planet’s magnetosphere which in turn captures the particles which make up the Van Allen Belts. However, the eddy currents cause the magnetic poles to invert every few hundred thousand years (we are currently overdue for such a flip). The South Atlantic Anomaly is a manifestation of the “weather” in the molten outer core of Earth–a prelude to the magnetic polar flip. First generation spacecraft used solid state components and had big ungainly robust circuitry. Additionally they were hardened against radiation. Some of today’s craft make use of delicate & elaborate microcircuitry which is prone to failure when struck by esoteric radiation particles. This is how what happens far beneath our feet influences what happens to craft in outer space.
M-type asteroids are high albedo (i.e shiny) asteroids made partially or mostly of metal. Of all of M-type asteroids currently known in the solar system, 16 Psyche is the most massive. It is a hunk of iron and nickel (and other heavy metals?) which has a diameter of 250 kilometers. Psyche orbits the sun between Mars and Jupiter and is believed to be the exposed core of a planet approximately the size of Mars which was obliterated by a catastrophic impact. The asteroid is named after the intrepid mortal who found love and ultimately apotheosis in an “Eyes Wide Shut” type Greek myth of great suspense, horror, and beauty.
Are you curious to know more about 16 Psyche based on this description? I certainly hope you are, because NASA has just announced future missions for the 2020s and 16 Psyche is on the list. As currently conceived, the Psyche exploration mission will send a robot probe powered by solar electric propulsion out to the obliterated core to examine the planetoid. The probe will be equipped with a magnetometer and a gamma-ray spectrometer to find out more about the composition and history of the enigmatic relic.
Of course other long term aspects of the mission are of interest as well. Although we have not yet mastered nuclear fusion, safe comprehensive control of such boundless energy is probably only 20 years or so away [winky icon]. What if humankind had sophisticated manufacturing robots and near infinite energy? In such circumstances 8 million cubic kilometers of steel might come in very handy indeed. So far the good news keeps rolling in for 2017. This Psyche mission can’t happen fast enough for my taste.
ferrebeekeeper 