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For my culminating post, I want to reflect on how my perspective on space and the future of astronomy has changed over the course of Astronomy 201. Firstly, everything I learned in this course, from gravity and planetary formation to stars and habitable zones, has given me a fundamental and scientifically realistic understanding of space and our galaxy. I think we all grow up with some part of us pondering the dark vastness of space, and how it relates to the human condition. This class allowed me to take those essential, soulful curiosities and put them into concrete terms. As much as this concreteness has solidified my understanding of mankind’s astronomical world, I still view the universe as an inescapable enigma.

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Thinking about the future of astronomy for this post brings me to an interesting understanding of astronomy’s immediate importance for our civilization. I think that having a sense of the physical processes that shape our universe, and being aware of our surroundings in space (including potential dangers and possible benefits), are absolutely essential knowledge for the continuance and well being of our peoples.  For example, the ability to detect and avoid collisions with interstellar objects in an Armageddon-type scenario is no longer the sole product of Hollywood’s special effects. Although these types of events are rare, I am grateful that astronomy and technology have made us less helpless in the realm of space. More realistic, however, is our potential need for resources on other planets, or even colonization off of Earth. This point leads me to the more biological concept of Malthusian catastrophe and the idea that Earth, despite our best technological efforts, cannot indefinitely support our exponentially growing population. Although there are many ways we could lessen population strain on our planet (our negative environmental impact could arguably be included as strain), it is difficult to argue that such changes can or will be effectively pursued by Earth’s population before catastrophic occurrence. I strongly believe that astronomy is one of the few sciences that might be able to save us from catastrophe, and it may be the most promising.

Fermi’s paradox, Fermi’s question, the Great Silence, and Silentium Universi are all names ascribed to one of the most fundamental questions of astronomy: “Where is everybody?” It is a question based in rationality, because in the search for extraterrestrial life the numbers just don’t seem to add up. With enough probes and some decent rocket technology, it is theorized that the Milky Way Galaxy could be explored in at least 4 million years. Sure, 4 million years seems like a long time for our young and galactically dinky civilization, but our galaxy is more than 10 billion years old and technological advancement is an exponential phenomenon.

Scientists have considered a variety of possible explanations for the paradox of Silentium Universi. The first of these solutions is that aliens are here. They came and left leaving evidence behind, or they are us and humans are actual descendants of ancient alien civilizations, or aliens are actually keeping us in a well designed zoo of sorts. The second solution is that aliens exist but we have not yet communicated. It is possible that we do not know how to communicate properly, that it is only a matter of time before we do communicate, that we are being purposely avoided, or that civilizations simply do not last long enough to ably cross-communicate. The third solution is more pessimistic, and theorizes that life simply does not exist elsewhere, or that the genesis of life is extremely rare. It is difficult to conclusively say which solution is most likely, as we have little understanding of the processes that develop intelligent life.

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The search for extrasolar planets and potential for alien life is one of the hottest topics in modern science. As such, I thought it would be interesting to discuss the place that some scientists say is most likely to alien host life.

Enceladus seems to be at the top of everyone’s list for alien host planets. This small moon of Saturn is called the most promising bet for life for several reasons. Its surface is icy, but scientists believe there may be water beneath the surface ice. Also, the moon seems to have a boiling core of molten rock, helping to heat the moon to warmer temperatures that can help give rise to life. The most attractive characteristic of Enceladus is the geysers of frozen water spewing from its southern hemisphere. If there is life on Enceladus, these geysers may be continuously gushing life into space, making it easier for scientists to grab potential samples.

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Scientists have located what they believe to be the first direct observation of a planet forming in its stellar womb of gas and dust. Using ESO’s Very Large Telescope, Sascha Quanz and an international team of scientists has been studying the young star HD 100546 and its surrounding gas. They were surprised when they spotted a protoplanet, about 10 times further out than the Earth is from the sun, still being formed. The discovery is exciting for several reasons. Firstly, the youthful planet and its star are relatively nearby to earth at 335 light-years away. But even more importantly, “if [the] discovery is indeed a forming planet, then for the first time scientists will be able to study the planet formation process and the interaction of a forming planet and its natal environment empirically at a very early stage.” Current understanding of protoplanet formation relies heavily on mathematically based theories and computer models. Scientists note that the results of the study require follow-up observations to confirm the existence of a protoplanet.

The greatest barrier to human exploration of space is undoubtedly the vast distances and time lengths required to travel from one stellar body to the next. This post will outline some potential modes of interstellar propulsion:

Magnetoplasmadynamic (MPD) Thrusters

As described by NASA, MPD thrusters are the most powerful form of electromagnetic propulsion. They use charged particles from ionized gas as fuel (xenon, lithium, neon), feed them into an acceleration chamber and out a nozzle to produce thrusts of up to 200,000 MPH. Unfortunately, these thrusters require hundreds of kilowatts to generate acceleration, requiring power generation on the scale of nuclear power plants.

Bussard Interstellar Ramjet

The Bussard Interstellar Ramjet propulsion system draws its fuel from space itself. Developed in 1960 by Dr. Robert Bussard, this “ramjet” uses an electromagnetic field to collect interstellar hydrogen, which is compressed in the craft’s cylinder shaped body and expelled as propellant for a fusion rocket. The speed of the craft is mostly dependent on the density of hydrogen in front of the vacuum-like Bussard Collector. Some estimate that the Bussard Ramjet could move at 77% the speed of light. (The EnterpriseD has two “Bussard Collectors” that were used as emergency fuel sources for the warp drive).

Solar Sail and Beamed Solar Sail

This technology is true to its name and very real. Solar sails use solar photons to push a hair-thin reflective carbon-fiber fabric in a fashion similar to using wind against sails to move across water. This technology has been successfully created by NASA and put to use by the Japanese. IKAROS, a Japanese solar sail, traveled to Venus in 2010, proving the technology for intrasolar missions. Solar sails to not need fuel, but are propelled via solar pressure or self-generated lasers. Because of its sail mechanics, this craft takes years to build up speed, but can reach velocities of 100,000 MPH and more. – Latest solar sail project from my hometown!

The US National Snow and Ice Data Center (NSIDC) based in Boulder, Colorado, has been taking images of our planet for 34 years, documenting climate changes and ice levels across the planet. Data from the past five years show ice levels to be lower than any previously document years. Changes in climate and ice levels for the year 2012 entirely surpassed expectations and thoroughly shocked many scientists and climatologists.

On August 26th, 2012, the NSIDC recorded record-breaking ice-melt levels. The ice had dropped to 4.1 million square kilometers in the Arctic. This ice covered 70,000 square kilometers less and occurred two weeks earlier than the previous record low in 2007. According to a report released by the NSIDC on September 9th, that figure dropped by another 14% to around 3.52 million square kilometers, evidence of a rapidly increasing melt rate. Some scientists agree that the observed drop in sea-ice coverage suggests that the Arctic could be seasonally ice-free as early as 2030 [1].

For scientists, Arctic ice is a fundamental indicator of climate change because of its sensitivity to warmth and the key role it plays in amplifying climate change. Water under the ice pack (known as the halocline) could be warming due to climate warming and ice melt. The warming could, in turn, melt sea-ice and the carbon-rich permafrost beneath costal waters, releasing large amounts of greenhouse gases into the atmosphere [2]. The release of long-stored greenhouse gases would likely contribute to a cascading effect of global warmth, trapping more heat from the sun, melting more ice, and thickening the atmosphere.

This scenario of melting ice and increasing warmth is frighteningly similar to the runaway greenhouse effect responsible for Venus’s (Earth’s “sister” planet) climate. On Earth, large amounts of carbon are trapped in ice, water, in the oceans and in materials such as surface minerals. On Venus, there is no water to dissolve and trap carbon, so it exists gaseously free in an atmosphere made up of 96% carbon dioxide. Climate warmth on Earth could potentially release a lot of its trapped carbon into gaseous carbon dioxide, contributing heavily to the greenhouse effect on Earth. In essence, climate warmth and ice melt will bring us closer to the atmospheric composition of Venus, which is often equated to hell.

– How will the little kids of the future ever believe in the wonder of Christmas, Santa Clause or claymation without an ice-covered North or South Pole?… & what about Mr. Snow Miser?

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On July 5, 2012, the world’s largest laser fired a record shattering shot that generated more power than the entire United States does at any given moment. The laser, located in Livermore, California, is housed in a building the size of three football fields dubbed the National Ignition Facility (photo above). The NIF laser is an extraordinary machine of precision. Each experimental shot requires the coordination of 60,000 control points including motorized mirrors and lenses, sensors, amplifiers, cameras and more, ultimately targeting a point about the size of a pencil eraser. 192 beams of optically amplified, electromagnetic radiation-emitting light, that all fire within a few trillionths of a second, combine to produce 500 terawatts of peak power and 1.85 megajoules of ultraviolet laser light.

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Funded by the National Nuclear Security Administration (NNSA), the NIF’s primary mission is to provide a better understanding of the physics behind nuclear reactions. However, this remarkable technology is also helping to conquer the physical barriers of scientific observation. The laser can generate temperatures of more than 100 million degrees and pressures more than 100 billion times Earth’s atmosphere. These conditions can potentially simulate the extreme states of matter found in the cores of planets, stars and other celestial objects, giving astronomers and physicist an unprecedented view of stellar mechanics. One hopeful goal for the NIF laser is to develop an understanding of fusion ignition, the point at which nuclear fusion (the process by which stars burn) becomes self-sustaining. Achieving laboratory fusion ignition would theoretically allow scientists to provide abundant and sustainable clean energy through nuclear fusion by converting mass into incredible amounts of energy. Experts still speculate on the timeline of such achievements, noting the technical challenges of putting star stuff in a container.

For more images and videos of the NIF laser, including a fascinating Ted Talk by Dr. Ed Moses, click the second photo above!

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Spectroscopy refers to the interactions between matter and light, or radiated energy, and the dispersion of an object’s light into its various wavelengths (i.e. colors). Dissecting an object’s light through spectroscopy helps modern astronomers determine the physical properties of stars. However, the study of light aids more than just astronomers in scientific battles today. New technology known as HINS-light (high-intensity narrow-spectrum) is utilizing nuances of spectroscopy to fight off highly resistant hospital bacteria that plague health systems nation wide. Developed at the University of Strathclyde in Glasgow, Scotland by a multidisciplinary team of experts, the HINS-light decontaminates the air and exposed surfaces with a light focused on a narrow band of visible-light at a 405 nm wavelength (violet). The new technology kills pathogens and is harmless to patients and staff, allowing for the continuous decontamination of hospital rooms. The HINS-light works by using its narrow spectrum of light to excite molecules within bacteria, which then release highly reactive chemicals that are lethal to the tiny prokaryotes. Clinical trials proved the current HINS-light system capable of reducing surface bacterial levels by 86%!

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  1. Tycho Brahe: Tycho’s primary contribution to astronomy is his collection of stellar and planetary observations. Accurate to within one arcminute, Tycho’s naked eye observations were unprecedented in quality. Tycho proved that comets lay in the realm of the heavens and sought to improve upon the current model of the solar system. Although Tycho never lived to completely fulfill his goal, his work lived on through Kepler who can be attributed with the discovery of elliptical orbits.
  2. Major Historical Events:
    1. 1585 – Under orders by Queen Elizabeth I, the British found Roanoke Colony on Roanoke Island, on the outer banks of North Carolina. The colony was a preliminary attempt to establish permanent colonization. The settlement is infamous for the disappearance of its inhabitants in 1590, which earned it the nickname “Lost Colony.”
    2. 1591 – Sir John Harington of Kelston creates the first flushing toilet. Harington introduces his invention in a book titled A New Discourse of a Stale Subject, Called The Metamorphosis of Ajax. The book not only proposes a new model of urban sanitation, but also provides a stage for needed social and political commentary.
  3. Sir Francis Bacon (1561-1626) was one of the most notable figures to have lived during the time of Tycho Brahe. Serving as the Attorney General and Lord Chancellor of England, Bacon is often considered the father of empiricism and the originator of the scientific method. He established the Baconian method – the idea of reasoning by deduction, or drawing conclusions from accumulating data – in his book Novum Organum.
  4. This period in history was incredibly interesting to review. The happenings during the 16th and 17th centuries seemed to be fundamental in creating the physical structure of our modern world. The cultivation of political theory through figures like Bacon and Elizabeth I, and the scientific fervor displayed by figures like Brahe and Kepler helped to prepare us for a global society. The exploration, colonization and scientific achievement created a more complete picture of our world and its solar system (heliocentric universe). The impact of scientific figures like Galileo Galilei and his contemporaries have shaped the path of modern science by challenging ideologies that had stood for centuries. Developments during this period reveal a time that was most fundamental in creating modern science.

Precession: The Great Year

As humans on Earth there are two celestial motions that affect us most obviously. Earths diurnal motion, its rotation on its axis responsible for day and night, and Earth’s revolution around the sun, determining our yearly cycles (winter, spring, blooming, hibernation, migration). A third and less obvious celestial motion is precession. Its time scale hides the immediate impact of precession, as the human being has a life span of one-360th of a roughly 24,000-year precession cycle.

In the book Hamlet’s Mill, Giorgio de Santilla, former professor of the history of science at MIT, and coauthor Dr. Hertha von Dechend, explain how ancient cultures viewed consciousness and history as a cyclical cycle. In contrast to our linear model of time, these cultures believed in a vast cycle of time that consists of the rising and falling of ages, and moves with the precession of the equinox. Santilla and Dechend show that more than thirty ancient cultures believed in this cycle that Plato called The Great Year.

In the hyperlink above, you can read about the thinking behind these precessional cycles and how a moving Solar System might provide a logical reason for The Great Year and alternating ages.