HW #7 Tim Clark

1.         There are a couple different aspects of life and evolution that could help explain the Fermi Paradox. As I allude to in the second question, I think it is a bit naïve to assume and expect other evolved races or civilizations to 1. Communicate at all outside their world, and 2. Communicate the ways we do or the ways we expect them to. We see in our modern world that there are intelligent indigenous tribes that do not and have no motivation to communicate with other planets in or outside of our galaxy. Also our race’s evolutionary process has led us to believe that radio waves, pulsating lasers, and other things are the best way to communicate with other civilizations. It is shortsighted to think that because we use these means, other completely foreign and alien races would do the same.

                Human civilizations have been traced back to 6,000 years old. Meaning the lifespan of our communicable race is not even 10,000 years old. That is a blip in the life span of the universe. That said in the 6,000 years we have existed, we have had thousands of natural disasters, plagues, and been hit by dozens of asteroids a year. These events have killed millions of people over the course of our existence. A different magnitude in some of these events or slightly bigger asteroids could have devastated the human race and potentially could have sent us into existence. I say this to say that even though we have survived we in our industrialization have increased global warming and based on prediction could have brought the survivability of Earth to 0 even in the next 1000 years. That said the life span of other intelligent life could be just as small as ours which could be 7,000 years or so. We are going to be forced to invent solutions to solve global warming and increased energy needs or will die. I feel like most civilizations will come to this breaking point and because we are (and assume they are) flawed beings, we could fail. With the possibility of the life spans being shortened it could bring on the assumption that the alien race would not be able to produce communicable data in the life span they have.

                 Lastly on this point I think the time frame of evolution is something that we have overlooked and assumed is universal throughout the universe. We live in a setting where time is determined by the astronomical occurrences of our Earth rotating on its axis and also its revolution around our star. Our concept of time is built on these variables, but it can easily be inferred that little to know habitable planets that could have life would have the same quantities for time. That said I think the evolutionary process in which intelligent life is created cannot be assumed to be the same time period because time is relative to the existence and ecosystem you live in. As we have pointed out also colder climates would inherently take a longer period of time for anything to happen just because of the fact that molecules and atoms are moving slower. That said combined with the idea that life spans of races are probably too short to establish communicable means and be able to travel to us, then it is highly improbable that intelligent life exists beyond our own and if it does then it is totally possible it is communicating in a way we cannot understand or that they can’t understand us.

2.   Based on the Drake equation, I would be considered somewhat of a pessimist, and that is ok with me because I am. I think I am being generous when I say that there  are .0037 communicable civilizations in our galaxy. By extension this would mean I am inferring that there are 740,000,000 possible communicable civilizations in the universe(.0037*200,000,000,000 [# of galaxies in the universe]). In my opinion this number should be lower. I say this because the original drake equation ne was defined as the number of planets that were in the habitable zone not what the above states “are suitable for life.” Because of this and the mission of Kepler the now known quantity for that variable is 10%. Habitable zone primarily references the temperature of the planet based on the stars luminosity, size, and distance the planet is from the star. The fact of the matter is that there are some key variables that are left out when ne is defined as planets in the habitable zone, which would decrease the quantity of ne from 10%. Some variables that are not taken into account are whether or not the planet has a magnetic field, an atmosphere, the chemical composition needed for life, and the presence of water, methane, carbon, silicon, or other necessary molecules or atomic ingredients. Because of that I believe that the quantity for ne would be drastically lower, I would say a fraction of 1% of the planets of the planets in a system would be in the solar system AND would have all these necessary characteristics. When I changed the ne quantity to .0005 the number of communicable civilization in our galaxy would be 1.9e-05. Therefore I am guessing there could be 3,800,000 potential communicable civilizations in the universe. Although I am still skeptical of that number, it seems closer to reality in my opinion.  

Another reason I believe that the number of communicable civilization in the universe is more philosophical. I think the nature of evolution for different civilizations cannot be defined as ours is. I think it is naïve to think that other civilizations that would most likely be incredibly more different than ours would have/want/desire communicibilily. We as modern humans are wired in a certain way to expand, grow, evolve, question things, and ultimately make life easier for ourselves. I do not think that we can assume the motivational makeup for other creatures would be the same and result in the same technologies and idealistics that we have. Even we as humans don’t always evolve to the same capacity. There are millions of indigenous peoples still across the world making up nearly 1/5 of the different people groups across the world and their desire and motivations are not to use and apply technology in communicating to one another or aliens. They have a different set of idealistic ideologies that are not like the modern civilization’s citizen. I am generalizing yes, but the point is that their evolutionary process did not see profit in the need to assimilate into a culture that would be able to communicate with other plants. Based on these examples we see on Earth, I think it would be easy to understand that even if there were intelligent life, their motivational makeup could have nothing to do with communicating with beings beyond their own world. We cannot say their ideologies would be the same or even close to the same as our own because their physical, chemical, and social norms would be based on an environment that is completely different from our own. That said I would decrease “fraction of planets with intelligent life that develop a technological phase during which there is capability for and interest in interstellar communication,” variable down to .0001. My number for life in the universe would decrease to 3,800. I am most comfortable with these inputs.

 3.            If I were to make a message for the stars I would base practically everything on it to what Stephen Hawking said about extraterrestrial life. His viewpoints about ET life were paralleled with those of when Europeans colonized the Americas. He said that we as humans would be as the Native Americans and would had vastly less technology to defend themselves when the Europeans conquered. Hawking said this is what it could and probably would be like if there was an alien race advanced enough to get from where they are to Earth. With that foundational belief I would design my message, and nothing I would put in the message would give 100% to our race as humans, our location in the galaxy, our ecosystem, nor even the location at which we transmit our signal.

                Firstly, instead of describing the human anatomy and the physical pros and cons, I would strategically put illustrations and characteristics of dolphins instead of humans. I would do this for two reasons. The first is that I would not want the advanced civilization interpreting and analyzing this to understand the anatomy of humans with our weaknesses being able to be extrapolated from the designs. Looking at our anatomy they could understand the fragility of our existence and understand the weakness of our soft and smooth exterior seeing we don’t have a thick outer shell. Also we look wimpy (compared even to animals on Earth like gorillas, elephants, and lions). Secondly if we gave the interpretation that we were dolphins and not humans the ET’s could extrapolate we live in and are limited to water, yet again undermining us and being underprepared if they ever came. Also I would exaggerate the size of the dolphin described for intimidation purposes.

                When describing the location of where we are in the universe, I WOULD NOT give them our direct location. I would give them coordinates to a surrounding star or galaxy that is somewhat easily observable by us. What I imagine this would do would 1. Not let them know exactly where we are (!), and 2. Would let us observe their ships or communications or weapons if that’s what they did, from safeish distance. This would potentially give us insight on the nature of the alien race, and plan accordingly for future encounters.

                Going along with this idea of misleading the alien race of our location I would transmit the signal (I was thinking we would use the pulsating laser) from a different source than Earth. We talked last lecture about sending laser equipment to Mars to fire back at Earth. What I would suggest would be similar, but much farther away. I would have a satellite or rocket launch well outside of our solar system, and them fire the signal laser at the satellite that would then transmit the information outward into the universe from its location, which is always changing, getting further and further away from us.  

HW #7

1) What would be your best guess as to the solution to the Fermi Paradox, and why?

The Fermi Paradox brings about the conflict of the naivety if thinking humankind is overtly special and the fact the we haven't found any other intelligent civilizations to disprove that idea.There are many possible theories that I believe all play a part in the solution to this paradox. I think it would be rather rash to say that any one reason was the answer. The universe has existed for nearly 14 billion years, leaving lots of time for civilizations to come and go before we would ever even begin to dream of their existence. We have no way of knowing if there have been other advanced civilizations in the past or if there are currently civilizations simply too far away to feasibly be able to even detect at this time. It's not entirely unreasonable to think about the possibility of an intelligent civilization that developed and died out. It's still unclear as to what the life span of a civilization is. There have been many eras on Earth where the global ecosystem was destroyed, the Great Dying of the Permian Era is just one example of that. Humans are consuming energy at an alarmingly increasing rate, which will bring about our extinction if we are unable to find sustainable solutions. Although there's no way to truly know, I think it's safe to assume that other civilizations would face similar threats. Some may be able to overcome them, but others could die out. Since we have never expanded to a galactic civilization, we don't really know what it takes to accomplish such a feat. It's possible that our estimations for how many civilizations with Von Neumann there should be are far too high. Currently, all we can do is speculate as to what the solution could be.

https://en.wikipedia.org/wiki/Permian%E2%80%93Triassic_extinction_event

2) What would be your best estimate of the number of intelligent civilizations in the Galaxy and why? What about the entire Universe?

If I were to estimate the number of intelligent civilizations in the Galaxy I would utilize the Drake Equation, partly because that's the only method I know and partly because it seems logical to do so. While it isn't perfect, there are many factors we don't have exact numbers for yet, the basis of the equation is a reasonable concept. There are some variables however, that we do know, such as the rate of star formation, stars with planetary systems, and how many of those planets are within the habitable zone. For there to be an intelligent civilization though, there must first be life to start with. So we would start with plugging in all of the known variables and then fill in reasonable estimates for the unknown ones. We know that at the given rate rate of star formation and the fraction of good stars that have planetary systems is approximately 100 billion and 1 out of every 10 planets in those systems sit in the habitable zone. We are working towards eventually being able to determine which planets have the possible basis for life (as we know it) and how many there are. Currently, I would guess that out of the ~10 billion planets in habitable zones, 1 in 50 of them fulfill the requirements for life. That leaves 200 million planets as possible homes to other forms of life, but now we have to take into account how many living species develop intelligence. There have been several dominant species on Earth throughout the planet's history, only a few of which developed into what we would call intelligent species. I estimate that .1% of species develop into an intelligent species, but then that still leaves the question of how many intelligent species have the communication technology to receive and send signals for detection. While dolphins are generally accepted as an intelligent species, they do not have the advanced intelligence to develop galactic communication technology. So this number gets smaller still, and I would say that only .1% of intelligent species develop communications technology. That leaves a hypothetical 20,000 planets in our galaxy that could harbor civilizations advanced enough to seek communication with other civilizations. This estimation is for only one galaxy, the number is obviously much larger when you take into account the entire universe. As of October of this year, it is estimated that there are at least 1 to 2 trillion galaxies in the universe. For simplicity's sake I'll just multiply the estimated number of civilizations in our galaxy by the number of galaxies in the universe, giving us a possible 2x1016 advanced civilizations trying to communicate.

https://www.spacetelescope.org/news/heic1620/

3) If you were to design a message to the stars, what would you put in it and why?

If I were to send a message into space for other civilizations to pick up, it would be similar to what the Voyager spacecraft carried, and I would most definitely include music. Music is one of the best ways to convey feeling, culture, and beliefs when there is no common language. Specifically, I would include "Jupiter" from Gustav Holst's orchestral suite The Planets. It's a beautiful piece that includes many different styles, though I'm partially biased because my high school's alma mater uses part of it. I think it's important to include something conveying the core of humanity, such as music, but I would also include pictures of people from all over the world making facial expressions of the basic emotions like happiness, sadness, and anger. I would also include samples of dirt and plants and rocks to give other civilizations an idea of the composition of our planet and the structure of our life forms. The Pioneer missions included a plaque depicting human anatomy, the hyperfine transition of neutral hydrogen, and our solar system including the trajectory of Pioneer 10. I would definitely include the depiction of hydrogen and our solar system. In particular I think showing which way the spacecraft went in regards to our solar system is important because that would give any possible civilization an idea of where to send a return signal, assuming they are peaceful.

https://en.wikipedia.org/wiki/Pioneer_10
https://en.wikipedia.org/wiki/Voyager_program

Homework #6

Ch9Q38: Lesson for Life: Considering everything we’ve learned about the possible habitability of Jovian moons, make a list of what you think are the three most important lessons that apply to the search for life in other solar systems. Describe the importance of each lesson clearly, and conclude by summarizing how the study of Jovian moons as changed our perspective about life in the Universe.

     1.) Tidal Force can heat far away moons - When we search for life we initially look to planets that have an atmosphere and are in the "goldilocks zone" so that water can be liquid; however, the tidal forces evident in the relation Jovian Planets and there moons can mimic the same conditions for the temperate zone. Meaning we can find life in more places than previously expected.

     2.) Water is not the only liquid medium - Water is the liquid medium of our planet and therefore when in search for life we look for water as the liquid medium; however, methane and ethane, with there lower freezing temperatures, are liquid at much colder temperatures compared to space. This does mean chemical reactions are slower and the life would not be life as we know it, but it does mean that there are more places to search for life

     3.) Moons are very diverse - When we think of moons we look to our own moon as an example, a dead chunk of rock that could never support life as we know it, but moons can be very diverse as shown by Europa's and Ganymede's oceans.

Ch10Q48: Habitable Moons: As we’ll discuss in Chapter 11, some of the newly discovered exoplanets are Jupiter-like in size but are located at Earth-like distances from Sun-like stars. These planets are unlikely to be habitable themselves. Could they have moons with habitable surfaces? Explain.

     Yes, if they have an atmosphere and the combination of their current location and the tidal force is roughly equal to a planet lying in the temperate zone it would be habitable.

Ch11Q44: Explaining the Doppler Method: Explain how the Doppler method works in terms an elementary school child would understand. It may help to use an analogy to explain the difficulty of direct detection and the general phenomenon of the Doppler shift.

The Doppler Method is used by seeing how much a star wobbles back and forth. If it wobbles so much we can assume that a planet is tugging on it through gravity. Imagine a father swing a child around. The father moves back and forth as his son is pulling on him while in the air, even though the father is much bigger than the son.

Homework #6

CH9 Q41:

                If the oceans are made of water as we suspect then yes, we could definitely find some dissolved O2 in Europa’s ocean. As explained in the book, as high energy particles from the sun slam into water molecules on Europa they can cause chemical reactions which can alter the chemical composition creating oxygen in the oceans. Therefore, theoretically if we could transport fish from Earth to Europa they could potentially survive. It would have to be fish that can withstand extreme cold (which some can). Other forms of life that could survive on Europa would probably be more primitive forms of life that are single celled such as bacteria. We could find hypothetically aerobic and anaerobic forms of bacteria on Europa since there could be a presence of O2 on the moon. Multicellular organisms, although portrayed in the movie, more than probably do not exist on Europa if life does exist there.

CH10 Q50:

                The evidence that human activity can be summarized by the chart you (prof. Plavchan) presented in class. It showed the progression of natural occurrences on our Earth including volcanism, the El Nino effect, increased Sun activity and more, and how that has been predicted to effect temperature. Then CO2 increase in the atmosphere was presented which has been proven to have increased since the beginning of the industrial period on Earth. The effect of all the natural occurrences would have projected temperatures to have risen but only a degree or so more. This is not what actual temperature reading show. When the addition of the increase CO2 effect was added to the projections with the natural occurrences we see that the projections are accurate with the actual temperature increases being experienced on Earth concluding the deciding factor is CO2 increase in the atmosphere which has been shown to be caused by human activity. Simply put we need to limit our CO2 output throughout all mankind. This can be done following 2 ideas. The first is by creating a way in which to trap and/or chemically alter the CO2 emitted in the atmosphere. Underground basins have been given as a suggestion of a place to store the CO2. The second route is to limit and decrease the amount of CO2 emitted. This is tough because we as humans are becoming increasingly dependent on CO2 emitting fuel sources. Alternate avenues of energy are the solution for the train of thinking.

CH11 Q45:

                The transit method is a strategy in finding and identifying planets revolving around other stars than our sun. What we do is we take instruments that measure the light signature coming from other stars. The light that comes from a star is relatively constant. However, whenever a planet revolves in front of the star we see a dip in the light signature that we measure. This only works on planets that revolve in between its star and our visibility from Earth. If a planet’s revolution does not pass between its star and our visibility from Earth, we cannot use the transit method to find the planet. 

Homework #5

1. For a few of the most important past, present, or future robotic missions to the solar system, describe their targets, types, and mission highlights.
     Mars Opportunity Rover:
                                             -Target: Mars
                                             -Type: Rover
                                             -Highlights: Proved that at one point there was enough water to sustain                                                                      microbial life on mars

Voyager 1
                                             -Target: Jupiter, Saturn
                                             -Type: Flyby
                                             -Highlights: Launched during a special planetary lineup that only                                                           happens once every 176 years. Also, is carrying a time capsule of earth                                                 history
Europa Mission
                                              -Target: Europa
                                             -Type: Orbiter
                                             -Highlights: Has not launched yet but will study to see if Europa can                                                       support life
 2. What is the potential significance of atmospheric methane to the search for life on Mars? Are there other explanations for the methane?
     On Earth most Methane is accounted for by biological processes. However, it could just be that the Mars Rover experienced a local spike in methane that lay dormant under the martian surface.

 3. Describe the evidence for subsurface oceans on Ganymede and Callisto. What are the prospects for life on these worlds?
     Changing amounts of electrical currents beneath the surface of Callisto and Ganymede can point to a liquid ocean under their surfaces. If there was life on this world it would be very primordial due to the fact that chemical reactions are slower in colder climates.

HW #5

1. What happened to the gas that made up the much thicker atmosphere in the distant past, and what happened to the abundant water? What role did Mars’ small size play in these changes?

Most of the gas and water on Mars was stripped away due to solar ejections from our sun. Mars' small size and weak gravity meant that it didn't have enough gravitational pull to keep its atmoshpere from being stripped away.

2. What is synchronous rotation, and why is it so common among the Jovian moons? 

A synchronous rotation is when a moon's, or other body's, rotational speed matches it's orbit. The same of the moon would always face in towards its planet. Jovian planets are the largest in our solar system, and synchronous rotations occure with very massive objects that have a strong pull, making its moons fit into those todal forces. 

3.What are redox reactions? Give a couple of examples. 

Redox reactions, or reduction-oxidation reactions, are chemical reactions where electrons are transfered between atoms, a change in their oxidation state. Wood burning is an example of a redox reaction; carbon transfers electrons to the oxygen in the air. Combustion is a quick example, but this can occur over longer periods of time as well. The oxidation of iron, or rusting, is another example of a redox reaction where the electrons are transfered from the iron to the oxygen. 

HW #5

1. Briefly summarize the evidence from little over a century ago, both real and imagined that led to widespread belief in a Martian civilization.
   1. It was theorized that the surface of mars had canals that spanned the entire planet; someone even mapped the theorized canals from the polar ice caps interconnecting across the surface.
   2. Mars was approximately the same size as Earth and had about the same day length making people believe it was similar enough to host life as well.

 

1. Summarize the scientific pros and cons of sending humans to Mars. What other considerations are likely to play a role in decisions about such missions?
   1. Cons:
      1.  It is very dangerous!
      2. It would cost a lot more because we would have to provide life support vehicles as well as food and water and other things humans need to survive.
      3. For what we are looking for and the technology we have (if we were to compare cost to the benefit) it is much more efficient and safer to send robots to Mars for exploration right now.
   2. Pros:
      1. To infinity and beyond! It would be the greatest feat in human history going farther and exploring things we have never before.
      2. We could legitimately explore and experiment with Mars habitation and colonization.
      3. If life were to ever need to leave Earth we could have a tested plan for Mars.
      4. It would be easier to bring back and study Martian rocks if we were sending a manned mission.
          

3. Could Triton be habitable? Briefly discuss the possibility of finding habitable moons around Uranus or Neptune.
1. Yes. Although we as humans and astrobiologists have an understanding of what it takes to host and have life, we still cannot say with certainty that there is no life that can inhabit a moon like Triton. It might look completely foreign compared to life as we know it with different metabolite mechanisms and alternate sources of energy, but we cannot say it cannot happen.  So yes it could. If life were similar to ours it would have to be subsurface life closer to the hotter cores of the planet, and would most likely not be complex life forms but simple single celled organisms.
2. It is again a possibility life would have to be either quite different from how we know it here on Earth, or it would have to be insulated and protected by some feature of the moons. Again subsurface life would be most likely because of the intense low temperatures. I would said the possibility is there but the probability is low.

Homework #4

1.) Natural Selection is the process by which the members of a species with the best attributes live longer and reproduce more so that the species evolves
2.) Amino acids are organic compounds containing amine, carboxyl, and side chains. Handedness refers to how an amino acids are structured. Since almost all life is left-handed it gives further evidence to a common ancestry.
3.) A liquid medium is necessary for molecules to be transported for life to exist. Water is the best medium because it has a higher melting and boiling point than other mediums so chemical reactions happen faster. Other potential liquids are methane and ethane.

HW #4

1) Why is water so important for life on Earth? List the three major roles that water plays in metabolism.

A liquid of some kind is needed to allow organic chains and molecules to travel and interact. Water can get very warm, in contrast to other liquids on planets such as methane which is very cold in liquid form. Reactions happen faster in warmer temperatures than cold ones, allowing cellular respiration and other reactions to go quicker. Water also carries chemicals in and out of cells to ensure they get the nutrients they need.

 2) What do we mean by an “RNA World” and why do scientists suggest that such a world preceded the current “DNA World”?

The "RNA World"  was early in Earth's life when prokaryotes and other simple life forms were the only things inhabiting Earth. RNA was the original  genetic code, and its  simple design was easy to create. RNA was the precursor to the development of DNA. Eukaryotes, complex life, is based on DNA. At some point in the evolutionary chain, RNA found a way to pair up and replicate, and with replication came larger multicelled organisms.

 3) Summarize the three major environment requirements for life. Overall, what “litmus test” seems appropriate for constraining our search for habitable worlds, and why? 

One of the basic requirements of life are elements such as O, N, C, and H can combine in various ways to form larger organic molecules. Other requirements include energy and liquid water. Energy from sunlight works if the planet is close enough to the sun, and chemical energy is also another source of energy but needs atmosphere or liquid water. Liquid water is by far the most important requirement for life. It is a solvent that allows for molecules to move around and undergo reactions. A good "habitability test" would be to see how far away the planet is from its sun, in regards to the size of the sun. Since water plays such a vital role in all of the processes of life, we should look at planets that have the conditions for liquid water. There is the possibility to life based on something other than carbon, but water would still be  needed  to facilitate  transportation and movement within and between cells.

HW #4

1.       There are some similarities between the theory of gravity and the theory of evolution. For each theory they are at this point at commonly well proven theory. We see this based on the fact that through experimentation, we have seen repeated results time after time. This is analogous in each theory because we have empirical evidence that has been tested and proven for both gravity and evolution. There is another similarity between the two theories. They both have evolved (no pun intended) and changed over time. The theory of gravity’s modern day understanding started with observations traced back to Newton going through stages with Einstein and then progressing to the understanding we have of it today. Also both theories follow Occam’s Razor which is the idea that both theories are the simplest explanation for observations.

2.       The closest common ancestors appear to be single celled organisms, usually in the form of bacteria. By studying DNA sequences, we can see commonalities in the genome of species that prove a close relation. We can continue to do this, comparing and contrasting genomes between species. By doing this we can see the evolution's that genetics have gone through over time.

3.       We know the threat of impacts from meteorites and asteroids are real because we as humans have witnessed some of these impacts and the repercussions of them. One example of this is the fireball meteorite that exploded over a forest in Tunguska, Siberia. The energy released from the meteorites is estimated to been equivalent with 200 atomic bombs. We saw in WWII the destruction that just one atomic bomb can have. We have also seen the devastation a meteorite can have by witnessing the comet Shoemaker-Levy 9 slam into Jupiter in 1994. The explosion witnessed from Earth was approximately the same size as Earth. There have been more impacts from meteorites since then that have shown that there is definite possibility of devastating meteors striking Earth. 

Homework#3

     Sports are well-known for there use of superstition. This year Michael Phelps gained a bit of notoriety when we started cupping, and ancient form of Chinese blood-letting, in order to give him an edge in "letting out toxins and increasing performance." This practice has very little quality scientific evidence to support it and any studies done had a very low amount of test subjects and were very biased towards the practice. Most studies came out of of China which is notorious for biases towards in ancient medicinal practices. Any study done in a Western state with a large test pool has shown either no noticeable effects or even some negative effects in the form of anemia.

     It is thought that earlier in our solar systems life time there could have been more planets orbiting our sun that we have today. However, if these planets, and by extensions other planetoids, were to come  close enough to each other then by the Law of the Conservation of Gravity one of the planetoids could have sped up so much that it could have escaped our suns gravitational pull. This would have been extremely rare due to the large size of our universe and even our solar system. If we did discover a meteor from another solar system it could tell us what kind of materials are abundant in that solar system and even if that solar system have some of the necessary materials to support life as we know it

Homework #3

http://www.fxnewscall.com/ufo-sightings-2016-ireland-and-england-island-sightings/1955082/

# 59. The first problem with this article is that outside of a low quality photo there is no further empirical evidence that a UFO was seen or proven to have been in the sky that day. There is no other siting of the UFO except from this photographer reported which is means there is only one source of information. It is known in the Criminal Justice System that the worst kind of evidence to bring forward is eye witnesses. And if there is only one it makes the evidence that much weaker. Likewise, the evidence provided by the one source is subjective speculation information. According to him because the object is silver it must be metallic and therefore probably “scanned” a passage plan of its technology and copied it. On top of the fact it is an eyewitness, it is only one eyewitness, and on top of that he makes subjective assumptions with no real empirical evidence.

#51. The reason that the planets all formed in the motion they did and at the same time come down to two main concepts; the conservation of energy and the conservation of angular momentum. The nebular theory is the common understanding of the formation of the solar system. First we have a large cloud of gas that slowly start to collapse due to gravity. Based on the two concepts of conservation the cloud heats up and starts spinning as it contracts. Collisions between the particles in the cloud flatten the cloud into a disk. The Temperature is highest in the center and where the star forms. The other particles surrounding form the planets and continue the motion of the disk as the revolve around the central star. 

HW #3

Ch 2: #57: The Galileo Affair: In recent years, the Vatican has devoted a lot of resources to learning more about the trial of Galileo and understanding past actions of the Church in the Galileo case. Learn more about such studies, and write a short report about the current Vatican view of the case. 

Historically, the case of Galileo v. the Church has been one of the greatest controversies facing the Catholic Church. The Church has received much scrutiny over their conviction of Galileo and his heliocentric teachings. Charged with "heresy", Galileo lived the last 8 years of his life under house arrest, unable to share his theories on heliocentricity. Many people view this as the beginning of the separation of science and religion. People, mainly non-religious people, ridicule the Vatican for its outdated ruling. In recent years though, the Catholic Church has done further research into what really happened during the time of Galileo's trial. Much of the Vatican's defense for its past decision was that they simply wanted Galileo to teach heliocentrism as a theory to explain planetary motion and not directly challenge what was written in the scripture. 350 years later, Pope John Paul II removed the outdated ruling on Galileo's trial and had the Vatican formally embrace heliocentrism. In recounting the events of the actual trial however, the Catholic Church hold firm that they have always supported the sciences and that Galileo acted out of turn during and after the affair. They argue the fact that, at the time Galileo's claims did not answer the greatest evidence for geocentrism, the lack of  stellar parallax. The Church also points out that most people back then took a much more literal interpretation to the Bible, rather than the more metaphorical approaches we see today. Not only that, but in his book, Dialogue on the Two World Systems, Galileo ridiculed Pope Urban VIII who had been one of his few possible supporters. In the book, Galileo explains Urban VIII's views through the words of the character Simplicio, whose name can translate to "simpleton" in certain Italian dialects. While the Church has recognized its mistakes in regards to the Galileo affair, the Vatican also holds firm that given the circumstances, they made the right decision at the time.

Sources:
http://www.catholic.com/tracts/the-galileo-controversy
http://www.nytimes.com/1992/10/31/world/after-350-years-vatican-says-galileo-was-right-it-moves.html
http://www.history.com/this-day-in-history/galileo-is-convicted-of-heresy

Ch 3: #44: Our Cosmic Origin: Write two paragraphs summarizing why we could not be here if the Universe did not contain both stars and Galaxies.

Stars and Galaxies are part of a cycle where clouds of gas collapse and condense to the point where they form into stars and planets. Specifically, stars are born when the cloud of dust and gas is dense enough and get hot enough to undergo nuclear fusion and create energy. Throughout their lives, stars burn through their fuel supply for nuclear fusion. When they eventually run out, the stars explode and send its materials back to the empty spaces in their Galaxy. This left over debris accumulates over time and eventually forms a new cloud of gas and dust which will turn into a new star or planet. The cycle of stars created in Galaxies also gives way to the creation of planets. Without stars and Galaxies, there would be no planets, which is a clear example as to why we couldn't be here without them.

If a star is big enough, it can carry out nuclear fusion to a further point than just He. Given high enough temperatures and pressures, nearing the ends of their lives, stars produce carbon, oxygen, silicon, neon and many other elements through nuclear fusion. Once the star dies, all of these elements get sent out into space where they collect to form new stars and planets. It's these processes that provided us with the many elements that developed not only our planet, but our life. As Carl Sagan said, we are "star stuff". Without Galaxies, we wouldn't have stars or planets, and without stars, we wouldn't have the basic building blocks of life.

Source:
Life in the Universe by Bennett and Shostak

HW #2 Question #5

     Scientists have observed what they believe to be ancient riverbed on mars from an area known as Arabia Terra. They used new information from NASA's Mar's Reconnaissance Orbiter to find said information. The MRO has a resolution of 6 meters per pixel as opposed to the last mission that had 100 meters per pixel.

     Throughout history as people have looked at other celestial bodies they have thought to have found places where there may be water. Like the man we learned about in class that saw channels of water on the moon. As technology increases, however, these observations are much more credible. Still the only way to definitively prove whether there was water in Arabia Terra or not is to send a mission to the planets surface to analyze, such a plan is in the works now.

http://www.astrobio.net/also-in-news/fossilised-rivers-suggest-warm-wet-ancient-mars/

http://mars.nasa.gov/mro/news/whatsnew/

HW 2: #3 Arsenic-life Bacterium

“‘Arsenic-life’ bacterium prefers phosphorus after all”, written by Daniel Cressey, discussed the debunking of a previous article posted in 2010. The article, “A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus”, written by Felisa Wolfe-Simon & others, claimed that one of the bacteria in Mono Lake in California, which is very high in arsenic, could metabolize without phosphate and instead use arsenate. After several subsequent articles, this theory was proven to be false, and organisms need phosphate to grow. Specifically, an article published in October of 2012, “The molecular basis of phosphate discrimination in arsenate-rich environments” by Mikael Elias & others, tested to see how these bacteria even differentiate between the two extremely similar molecules. Being from the same group on the periodic table, phosphorous and arsenic have practically identical electronegativities and Van der Waals radii.

This was the foundation for Wolfe-Simon’s article, but much of their results and findings were viewed subjectively because they wanted the outcome to be true. In the research done by Elias and his colleagues, they discovered that not only could these bacterial proteins differentiate between phosphate and arsenate, they did so through one key chemical bond. They all showed an extreme preference for phosphate, particularly the one bacterium that began this controversy which filtered in phosphate at levels of 4,500-fold the level of arsenate to phosphate. Arsenate was clearly still needed for these bacteria due to the lengths they went to in order to bond with all of the phosphates they could. However, some of the bacteria were able to bond with the arsenate after depleting the supply of phosphate, though the hydrogen bond was much weaker when the bacterium bonded with arsenate.

a. P. fluorescens PBP bound to phosphate has a more direct connection

b. P. fluorescens PBP bound to arsenate has an angled connection

Knowing that bonds could occur with arsenate when given no other option opens the door to the possibility that there may be life on other planets that survive without phosphate, or in fact use arsenate preferentially over phosphate. It would be interesting to test these, and other bacteria, in a pure arsenate solution, removing their ability to choose phosphate over arsenate.

Sources:

‘Arsenic-life’ bacterium prefers phosphorus after all: http://www.nature.com/news/arsenic-life-bacterium-prefers-phosphorus-after-all-1.11520

The molecular basis of phosphate discrimination in arsenate-rich environments: http://www.nature.com/nature/journal/v491/n7422/full/nature11517.html#supplementary-information

A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus: http://science.sciencemag.org/content/332/6034/1163.full

http://chemical-elements.findthedata.com/compare/6-69/Arsenic-vs-Phosphorus