And now for something completely different as the Monty Python crew liked to say. I usually try to be as accurate as I can in these posts. I welcome any feedback that will help me correct mistakes. However, sometimes you encounter what seems to be a really far out idea but a scientist is offering evidence for that idea. I just couldn’t resist mentioning the proposal that there were several huge devastating nuclear explosions on Mars that heavily impacted the surface of that planet.
      Dr. John Bradenburg is a senior propulsion scientist at Orbital Technologies Corporation. In a recent interview, he stated that, “The Martian surface is covered with a thin layer of radioactive substances including uranium, thorium and radioactive potassium — and this pattern radiates from a hot spot [on Mars]… A nuclear explosion could have sent debris all around the planet,” he said. “Maps of gamma rays on Mars show a big red spot that seems like a radiating debris pattern … on the opposite side of the planet there is another red spot.”
      Bradenburg is suggesting that there was a natural nuclear explosion on Mars that was equivalent to a terraton of TNT in the northern part of the Mare Acidalium region of Mars where there is a lot of radioactivity. The explosion would have thrown up the radio-isotopes which have been detected by gamma ray spectrometry. Xenon 129 is present in the Martian atmosphere. This isotope has been seen on Earth where there was a nuclear explosion or meltdown.
        Skeptics say that the evidence presented by Bradenburg is ambiguous and could be accounted for by natural non-nuclear processes that took millions of years. Even if there was a natural nuclear explosion in the remote past on Mars, researching it would not take precedence over many of the current Mars projects such as the search for life.
       In response, Bradenburg says that he has talked to defense specialists who agree with him that there is evidence on Mars for a massive nuclear explosion. He points out that there was a natural nuclear reactor on Earth. About two billion years ago, a water soaked uranium rich ore deposit in Gabon, Africa actually started a self-sustaining nuclear reaction.
       Critics point out that any such enormous nuclear explosion on Mars would leave huge craters that should be visible today. Bradenburg says that the craters from a two hundred million year old explosion could have been completely filled with sand in the intervening years. On the other hand, if the explosion occurred above the ground like the Tunguska event in Russia about, a huge crater may not have been created.
      Currently, Bradenburg is leaving the question of what could have caused such an explosion open. In the past, he has suggested that there could have been an ancient civilization on Mars that was responsible for the big nuclear explosions. Needless to say, this idea did not find a great deal of support even among scientists who say that Bradenburg has raised some valid questions about Martian surface radioactivity. While the idea of intelligent life on Mars has been popular in fiction, there has been no solid evidence found of any life on Mars beyond the possibility of microbes.

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         I have been  blogging about Mars lately. Mars is the planet most likely to be visited by astronauts. The human race has been fascinated by Mars for over a hundred and fifty years. There were plans after we landed on the Moon in 1969 to continue on with visits to Mars in the coming decades. For political reasons, these ambitious plans were dropped and forty five years have passed since the Moon landing and there has been no visit to Mars. Now Mars is on the table again with NASA plans to send astronauts to Mars in the coming decades. With the advent of private companies developing their own launch systems and plans to exploit space, the urge to visit Mars has spread to the private sector.
        One of the barriers to visiting Mars is the projected length of the trip to and from Mars. With conventional engines and spacecraft, just traveling to Mars will take nine months. The astronauts will have to wait a year for the return trip which will take another nine months. Questions of fuel, supplies, psychological stress, and radiation damage make such an expedition very difficult and expensive. If the time required to get to Mars and back could be shortened significantly, the trip would be cheaper, safer and more likely to succeed. There are private companies working on spaceship engines that hold the promise of getting us to Mars much more quickly.
        The Ad Astra Rocket company in Texas is currently working on the Vasimr plasma engine. The company held a successful test of a prototype 2013. Now NASA is considering the use of the Vasimr engine for a Mars expedition. During the next three years, NASA will provide about ten million dollars to the AAR to get the engine “almost ready for space.” This phase will end with a one hundred hour continuous firing of the AAR VX-200-SS prototype. There have been more than ten thousand successful firings of AAR engines so far but these were all short firings. Continuous firing will be necessary for use in space missions.
        Plasma engines function by creating a ionized gas which is then accelerated by electromagnetic fields to propel the vehicle. There are many different designs for plasma engines. Very little fuel is required for a plasma engine. Water is a possible fuel. While the actual motive force of a plasma engine is weak, it can fire continuously for long periods and build up high acceleration over time. It is estimated that a Vasimr type engine could take a spacecraft to Mars in 39 days.
        With respect to such public-private project NASA has said, “Commercial partners were selected for their technical ability to mature key technologies and their commitment to the potential applications both for government and private sector uses.” and “This work ultimately will inform the strategy to move human presence further into the solar system.” There are three projects in progress, including Vasimr, to develop electric propulsion systems in the fifty to three hundred kilowatt range for space missions. Current NASA plasma propulsions systems function with less than five kilowatts. 

Vasimr engine.jpg

         Every major mature industry has a trade association. These associations hold conventions, publish newsletters, carry out lobbying for the industry and carry out research projects. Now there is a Space Trade Association for  the commercialization of space.
         The STA was formed by three people who had worked together with Planetary Resources, Inc. on a Kickstarter project. There are already companies and other groups working on the creation of space industry but these three decided that what was needed was a group “based on specific models describing technological, economic revolutions – how they impact the industrial system, change the economy, alter our social structures and create a new world.”
         They have identified five previous “Ages” of techno-economic revolution and they consider the coming age of space exploitation which they call the Space and Solar Age as the sixth such revolution. The founders of the STA say that each of the previous such revolutions went through a defined sequence of stages, each with ” their own specific needs and impacts.” Their goal is to ascertain what stage the space revolution is at and to apply their energies in providing what is needed and anticipating what impacts will result. Their analysis suggests that the new Space Age is in what they call the gestation phase. They believe that each revolution is preceded by such a stage and that this period will last about twenty years until some high-profile event that publicizes the arrival of the new Age.
      The STA has identified Seattle, Washington as one of the places that will be a hub for the coming Space Age. Seattle is a world leader in the two main enabling industries for the Space Age, aerospace and information technology. In addition, Seattle has robust competitors in wireless technologies and biotechnologies. The University of Washington in Seattle is one of the biggest research universities in the country. There are about eighty thousand people within twenty miles of downtown Seattle that are working in or supporting the main industrial sectors that will contribute to space exploitation. The STA wants to take advantage of the opportunities that are and will be present in Seattle in the coming decades. “We  want to take the innovation in the space industries already happening in the Seattle area and help focus it, permitting novel change to occur more easily. We want to reduce the informational frictions that can slow down the rate of change needed for a new techno-economic Age to begin.”
       The STA plans on having monthly meetings in the Seattle area with people connected to space industry in order to establish a stronger network between these people. They believe that this can help to shorten the time and reduce the confusion in the gestation period for the Space Age. STA will also have quarterly social events with invited speakers. They intend to work with local organizations to help new projects get started and funded.
       I appreciate the enthusiasm and intentions of the STA. As commercial products are either manufactured or mined in space, an industry trade association could play an important role in facilitating the emergence of a robust space industry.
Seattle aerospace workforce:

Seattle aerospace workforce.jpg

         The National Aeronautics and Space Administration is a U.S.  government agency charged with responsibility for civilian space programs and research in aeronautics and aerospace. NASA was established in 1958 by President Eisenhower. Most U.S. space exploration has been carried out by NASA including the Apollo Moon landing, the Skylab space station and the Space Shuttle program. It is currently participating in the International Space Station project along with other nations. One of the main purposes of NASA is foster a better understanding of the Earth through the Earth Observing System. NASA also researches the sun and other planets, moons, comets and asteroids with unmanned probes.
         The EOS consists of a variety of satellites launched into orbit around the Earth starting in 1997 to carry out extended observations of the Earth’s land surface, biosphere, atmosphere and oceans. EOS is the main part of the NASA Earth Sciences Enterprise. The purpose of ESE is “to develop a scientific understanding of the Earth system and its response to natural and human-induced changes to enable improved prediction of climate, weather, and natural hazards for present and future generations”. NASA’s EOS has been providing information about the causes and effects of global climate change since the program began.
        As a U.S. government agency, the U.S. Congress exercises oversight through committees in the House and Senate. The U.S. House Committee on Science, Space and Technology in the House and the United States Senate Committee on Commerce, Science, and Transportation in the Senate carry out NASA oversight and budget approval. The NASA budget reached a peak with the Apollo Moon mission at about one percent of the federal budget. Today, the budget is about one half of one percent of the federal budget.
       With last November’s national election, the control of the U.S. Senate passed into the hands of the Republicans. A junior senator with no special knowledge of science and technology named Ted Cruz was appointed to be the head of the Senate committee. The Republican party’s position on global climate change is to deny that it even exists. At a recent hearing, the head of NASA was called before the Senate committee. Chairman Cruz asked why NASA was spending time studying global climate change when its mission had to do with space exploration. The head of NASA had to explain that NASA’s mission was both to explore space beyond the Earth and to use Earth orbiting satellites to gather important information about what was happening on the Earth. In frustration, he pointed out that if the rise in sea level that is predicted to accompany continuing global warming drowned Cape Kennedy, NASA would be out of business.
        I find it appalling that the head of a Senate committee was either ignorant of the important work that NASA satellites did in studying the Earth or was simply pandering to the Republican disbelief in global climate change. Somehow, the Republican party seems to think that if they ignore a problem, it will go away. Unfortunately, that is not the way the world works.
Earth Observing System Satellites:

NASA Earth Observing Satellites Chart.jpg

         Mars has inspired generations of writers. Shortly after the Italian astronomer Schiaparelli first wrote about seeing “channels” or “canals” on the Martian surface in 1877. From 1880 on, writers were inspired by the idea of ancient dying civilizations on a parched planet. There were stories of trips to Mars and visits by Martians. In 1898, H.G. Wells published the “War of the Worlds” about an invasion of Earth by Martians in huge war machines.
       The Martian stories continued into the Twentieth Century. In 1912, Edgar Rice Burroughs began publishing his Martian stories about an American soldier being transported to a Mars populated by different antagonistic races battling for resources on a dying planet. He continued publishing Mars stories for decades and inspired many imitators.
      Many books, short stories, comics, cartoons and movies about Mars were produced up to the 1960s. Many different alien races, technologies, motivations and activities were envisioned. Mars fascinated humanity because it was possible that life could have evolved there. It was conceivable that people could actually visit Mars and, perhaps, even live there. Many stories were written about human colonies on Mars.
      Then, beginning in 1965 with Mariner and Viking probes flying by Mars returned pictures that were at odds with the popular understanding of Mars. In 1971, the U.S. Mariner 9 probe to Mars became the first spacecraft to orbit another planet. When detailed photos of the Martian surface were received from Mariner 9, it radically changed our understanding of Mars. There were no channels or canals. It turned out that the networks of lines seen by astronomers in the past were an illusion. There was only a scarred, frigid, desiccated world of craters, deserts, volcanoes, and canyons. There were no signs of any civilization or, indeed, life itself.
       Following the realization of how hostile Mars really was, the fiction produced after the Mariner revelations became more focused on human expeditions and colonization attempts. The concept of “terraforming” became popular in fiction as humanity attempted to radically alter the Martian environment to be more friendly to unprotected human beings. Often stories would include plots about Martian colonists trying to exert their independence from Earth authorities.
       Although Mars turned out to be a very hostile place for humanity, human fascination with Mars has endured, partly driven by all the fictional accounts during the Twentieth Century. It had been hoped that, following the landing on the Moon in 1969, human exploration of Mars would soon follow. However, interest and investment in space exploration and human expeditions to Mars waned. Only recently has interest in manned Martian mission risen again. One of the most interesting developments has been the efforts of a private company to enlist colonists for a one way trip to Mars to establish a colony. I will discuss this project in a future blog post.
Original cover of an Edgar Rice Burroughs Mars novel:

John Carter of Mars.jpg

         Last week, I gave a general description of Mars and a brief history. Human fascination with Mars led to many attempts to send probes across interplanetary space to conduct a close examination of Mars and send pictures back to Earth. Interplanetary exploration is very complex and difficult. It is estimated that as many as two thirds of the space probes sent to Mars either never made to Mars or failed to return any information to Earth. Some probes did arrive and sent back pictures of the Martian surface.
        In 1964, NASA launched two identical Mars probes called Mariner 3 and Mariner 4. Mariner 3 failed on launch but Mariner 4 launched successfully and, after a seven month journey, transmitted pictures of the Martian landscape as it flew past Mars. The images returned by Mariner 4 were the first close up pictures of another planet ever taken by the human race. More Mariners were sent to Mars, some failed and some succeeded. Mariner 9 was the first probe to achieve orbit around Mars. Detailed pictures of Mars and information about surface conditions were sent back to Earth by the Mariner Series.
        The Soviet Union began sending probes to Mars in the early 1970s. They sent a series of probes and actually landed two probes on the surface. One crash-landed and the other landed softly but only sent a few seconds of data transmissions. During the 1970s, the Soviets continued to send probes to Mars with partial success.
       NASA launched two probes called Viking 1 and Viking 2 to Mars in 1975. The primary purpose of the Viking probes was to search for signs of life in the Martian atmosphere and to examine Martian weather, Marquakes and the Martian magnetic field. There were indications that there might be life on Mars but the findings were ambiguous and continued to be studied upto the present. Many detailed images of the Martian surface were returned  by the Viking probes.
      NASA had attempted to launch a Martian orbital surveyor probe to provide detailed images of the whole planet in 1992 but the launch failed. Another mission was implemented which resulted in the Mars Global Surveyor mission achieving orbit around Mars in September of 1997. The MGS carried out orbital maneuvers and then settled into a circular orbit for its main mission in 1999. The MGS carried out observations of the entire planetary surface, the whole atmosphere, and even penetrated beneath Martian surface. The MGS returned more information about Mars that all the prior probes combined.
        The NASA Mars Pathfinder mission landed a base station and a rover on the Martian surface in 1997. The small robotic vehicle was called the Sojourner. It was the first successful landing of a mobile research vehicle on Mars. In addition to conducting scientific experiments on the Martian surface, Sojourner also allowed NASA to test a number of engineering designs for Martian landings.
         NASA and the space agencies of other countries continued to launch Martian probes and our knowledge of Mars has continued to increase. Landers have roved around the Martian terrain, taking samples and carrying out experiments. Most of the information returned by NASA probes have been archived and made available to the public.
Image of the Martian surface with color indicating elevation:

Mars Topo map.jpg

       

         I have blogged about U.S. and Indian space missions that have sent probes to Mars. Mars has fascinated the human race for centuries. First as a star representing a god in mythology and then as a planet close to the size and orbit of Earth. Mars is fourth planet from the Sun and the second smallest in the Solar System, only Mercury is smaller. It is roughly one and a half times further from the Sun than the Earth and consequently gets considerably less solar energy from the Sun. It has about half the radius of the Earth and its gravity is about one third that of the Earth. Because of the small size and low gravity, it only has a thin atmosphere of carbon dioxide with traces of other gases that is about one percent of the density of the Earth’s atmosphere. There are no bodies of liquid water on the surface of Mars so it has as much land surface area as the Earth. Its surface temperature averages about eighty degrees below zero Fahrenheit. Its year is about twice an Earth year and its day is close to the twenty four hour day of Earth.
        In 1877, an Italian astronomer named Giovanni Schiaparelli thought that he saw lines on the Martian surface which he called “canali.” This can be translated as canal, channel, ditch, trough, gully, etc. The English press chose to translate the word as canal. Subsequently, other observers saw lines as well but their maps did not match. An American named Percival Lowell dedicated his life to astronomy in 1894 after amassing a fortune. He built the Lowell Observatory in Flagstaff, Arizona. He spent a great deal of time studying Mars and trying to observe the canals that everyone was talking about. He drew many detailed maps and speculated that Mars had an ancient civilization that had built the canal system when surface water became scarce. These ideas fueled the imagination of writers who published novels about Mars and ancient civilizations.
       With the development of better telescopes and the coming of the space age, the canals were found to be optical illusions. Close images of Mars from space probes showed a desolate surface littered with craters and covered with sand. No evidence of any artificial structures has been observed to date, although some people believed that they saw buildings and monuments in the Cydonia region. Although surface water has not been observed on Mars, many surface structures suggest that at one time there were substantial bodies of water on the surface.
       Of all the planets in the Solar System other than Earth, Mars is the most accessible to human beings. Venus is very close to the Earth in size and composition but is locked in a super greenhouse status with a very dense and acidic atmosphere. Mercury is too close to the sun and has no atmosphere. There has been talk of manned expeditions to Mars since the dawn of the space age. In future articles, I will talk about some of those plans.
Schiaparelli drawings of Martian canali:

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      Titan is the largest moon of Saturn. It is also the only natural satellite of a planet in our solar system that has a dense atmosphere. It is also the only natural satellite where large stable bodies of liquid have been found on the surface. Titan is the second largest moon in the solar system. It is larger than the planet Mercury and fifty percent larger than the Earth’s Moon. Titan is primarily composed of water ice and rocky material. The atmosphere is largely nitrogen. The atmosphere is one and a half times as dense as the atmosphere of the Earth although the gravity is only fourteen percent of Earth’s gravity. The temperature is around two hundred and ninety degrees below zero on the Fahrenheit scale. Voyager and Cassini probes flew by Titan and the Huygens probe landed on the planet in 2004.
       There are three hydrocarbon polar seas on Titan with a composition similar to liquid natural gas. The largest, Kraken Mare, covers over one hundred and fifty thousand square miles. The estimates of the maximum depth of Kraken Mare vary between five hundred and one thousand feet. Saturn causes tides which result in complex shorelines with deposits of evaporated material.
        NASA recently held the 2015 NASA Institute for Advanced Concepts Symposium at Cocoa Beach, Florida. At the Symposium, NASA engineers presented a report on the Titan Submarine Phase I concept design. The report discusses a possible mission to Titan where the robot submarine would explore the polar seas of liquid hydrocarbons. The Titan sub would weigh a ton and use electrical propulsion for a ninety day mission covering over twelve hundred miles. The sub would have to be delivered to the surface of Titan by a lifting body that could survive atmospheric entry. The sub would be able to travel at about two miles per hour.
        Sending an orbiter with the sub to relay information to Earth would be cost prohibitive. Instead, the sub has a large dorsal fin with a planar phased-array antenna to send information to Earth. It would surface for sixteen hours a day to send data. Because of uncertainty about the density variations in the hydrocarbon liquid, the ballast tank system is still under development. Problems with atmospheric density and temperature means that instead of using air pressure to manage the ballast tanks, some sort of piston system will have to be built to force liquid in and out of the tank.
        NASA has not presented details about the purpose of the Titan sub mission but it will probably include a full set of research goals. The sub will probably study the structure and composition of the liquid hydrocarbons. Sediment from the bottom of the sea will probably be a target. Since Titan has so many organic chemicals, the sub might look for possible precursors to life on Earth.
Artist’s concept of Titan submarine:

NASA Titan Submarine.jpg

         It is estimated that there are about a half a million pieces of space junk orbiting the Earth. This junk includes ” spent rocket stages, old satellites, and fragments from disintegration, erosion, and collisions.” Space launches have to pass though this layer of junk. Some of the junk is orbiting in the same orbits of satellites and poses a threat of collision. Most of the space junk consists of small particles that are less than one centimeter in size. About three hundred thousand particles are between one and five centimeters in size. There are amost twenty thousand particles bigger than five centimeters that are currently being tracked.
        The damage caused to satellites by the smallest particles consists on erosive weathering like being sandblasted. Bigger pieces of junk can cause serious damage. There is a density of space junk called the Kessler syndrome beyond which interaction of pieces of space junk produce more particles than natural processes remove which would result in a run-away chain reaction. If this happens, human access to space could be severely limited. A number of companies have designed systems to remove space junk from orbit.
        The European Space Agency has proposed the e.DeOrbit mission in 2014. This particular mission would find pieces of space junk between five hundred and six hundred miles up that are in a polar orbit. There have been proposals for a variety of “capture mechanisms” including nets, harpoons, robotic arms and robotic tentacles.
        A Swiss Space Systems demonstration spacecraft called the CleanSpace One is slated for launch in 2018 from the back of a modified Airbus A300 jumbo jet. Upon launch, the CleanSpace One would rendezvous with a decommissioned SwissCube nanosatellite and then move the satellite out of orbit.
        The Japanese Aerospace Exploration Agency has designed an electrodynamic tether. When attached to a satellite, the tether would interact with the Earth’s magnetic field to impose a drag on the satellite, bringing it lower into the Earth’s atmosphere where it will burn up. The system is supposed to be tested in 2015.
         Texas A&M University has proposed the Sling-Sat Space Sweeper which would rendezvous with a piece of space junk and sling it toward the Earth to burn up in the atmosphere. Gaining momentum lost from the captured junk, the SSS would sail off to find another piece to remove from orbit.
         The United Kingdom has a proposal for using the drag of a solar sail to slow a satellite and drop it from orbit. It was supposed to be tested in 2011 but the design was not finished. Work continues on the project using experience from a nanosatellite that launched in February of 2013.
        Raytheon BBN Technologies in the U.S. has suggested a method for junk elimination they call Space Debris Elimination. This system would use bursts of air in the upper atmosphere to decelerate pieces of space junk in low Earth orbit. The bursts could be delivered by high altitude balloon or high altitude planes.
        Star Technologies and Research, Inc. proposes a solar powered system called the ElectroDynamic Debris Eliminator that would consist of a string of nanosatellites connected by a electrically conducting metallic tape that could be up to two miles long. It would knock space debris down as it passes through the Earth’s magnetic field and generates voltage. They claim it can clear all large pieces of space junk in low-Earth orbit in twelve years.
        Whatever system or combinations of systems are chosen and implemented to clear orbiting space junk, this is a project that should be carried out as soon as possible to avoid the Kessler syndrome.

Orbiting Space Junk.jpg

         I write a blog on nuclear issues at www.nucleotidings.com. One of the things I have covered on that blog is research on thermonuclear fusion. There are a number of different companies working on fusion reactors which will produce power by fusing lighter elements into heavier elements. There are several elements that are being considered by researchers to fuel their reactors. Hydrogen, deuterium, tritium and helium-3. Hydrogen is abundant on Earth. Deuterium or hydrogen with a neutron in the nucleus is present in terrestrial water in a ratio of about one atom of deuterium for every thousand atoms of normal hydrogen. Tritium is very rare on Earth. It is produced naturally by the action of cosmic rays on hydrogen in the atmosphere. It is also produced certain nuclear processes intentionally or as a by-product of other useful nuclear processes.
         Helium-3 is produced when tritium decays and it is extensively used for medical imaging as well as a potential fusion fuel. Helium-3 is not radioactive and, if a fusion reactor could be developed that would use helium-3 as a fuel, there would be no creation of radioactive waste or danger of serious radiation leaks.  Like tritium, helium-3 is very rare on Earth. However, millions of years of bombardment of the lunar regalith by the solar wind has produced helium-3 on the Moon’s surface. It is estimated that there may be as many as a million tons of helium-3 on the Moon. One ton of helium-3 contains energy equivalent to fifty million barrels of crude oil.
        China has a huge population and a growing economy. It currently burns great quantities of fossil fuels and has ambitions to build hundreds of conventional nuclear power plant. However, those two sources of energy will not be able to sustain China in the coming decades so they are exploring other sources of energy such as solar, wind and fusion. China also has an ambitious space program. They are very interested in creating a permanent manned base on the Moon. They plan to send astronauts to the Moon by the 2020s.
        If helium-3 burning fusion reactors can be developed and if China can establish a mining base on the Moon, China will have all the energy it needs without fossil fuels or conventional nuclear reactors. Given the climate problems caused by fossil fuel emissions and the decreasing supply on Earth, new sources of energy will be very valuable. If China manages to mine helium-3 on the Moon and return it to the Earth, China could sell helium-3 to the rest of the world. This would give China a huge advantage in international trade and great political influence. Other major space powers would have to respond with lunar mining operations of their own. There could be a new Moon race with helium-3 as the prize.
       There are international treaties that say that countries and companies are not allowed to own parts of astronomical bodies without permission of other nations and sharing what they obtain from astronomical bodies with other nations. Ultimately, the old treaties will be updated or ignored in a race to commercialize space. Hopefully these disagreements can be settled diplomatically and will not result in militarization of the Moon.
Artist’s concept of lunar helium mining:

H3 lunar mine.png