Final Post (Reflection)

Posted on May 1, 2018 by alcottastr2110

Image result for observable universe

The Observable Universe (Thus Far)

I learned quite a bit this semester and it definitely changes the way in which I look at the universe. Coming into the course I could name the planets of our Solar System and that is about it, so I basically had no previous astronomical knowledge. For the most part I found the course very interesting, though I am admittedly not particularly interested in some of the particular details as to how certain objects form. I did find it very interesting however, to learn about the different characteristics of other worlds and simply how much more there is to learn. My eyes were opened to the sheer scope of the universe and how insignificant our Solar System is compared to it. As a result, I find myself thinking a lot more about other worlds and the possibility of alien life. Before I would say I didn’t really believe in alien life, but that is simply because my knowledge was so limited. As far as I knew, Mars was the only world we knew of with the possibility of life. I had no idea about places such as Europa or Titan. Now I feel like there has to be at least some form of life on a place like Europa in which there is likely an enormous ocean. It is hard to imagine any sort of ocean that would be completely absent of life. I also had no idea how many other habitable planets existed outside of our Solar System. I think the likelihood of alien life was really put into perspective for me when we all used the Drake Equation in class. Although I probably still fell more on the pessimistic side, I found myself thinking more and more about how unlikely it seems for us to be the only world containing life. I definitely want to pay more attention to future astronomical discoveries going forward and I find myself increasingly excited about the idea of learning about the physical characteristics of other Earth-like worlds as our technology gets better.

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The Fermi Paradox and the Great Filter

Posted on May 1, 2018 by stellarastronomy1995

The claim that because we have yet to interact with intelligent life beyond Earth, extra-terrestrial life therefore does not exist, is as unsubstantiated as an observer claiming the oceans are verifiably devoid of life as evidenced by the sixty seconds in which he/she glanced at the water’s surface from shore. If our galaxy were teeming with life however, is it not safe to assume that evidence of this abundance of life would present itself rather clearly to the casual observer? Given the ten thousand million year old age of the galaxy, would not one out of the many civilizations that have potentially come to be in this time have spread to the viable star systems, their existence even being obtrusive into human observations?

Enrico Fermi suggested just this. Given the time aliens have had to populate our galaxy, they should have done so already. Enter: The Great Filter (this is a great video explaining the general premise and its implications).

Great-Filter1
Rough illustration representing The Great Filter timeline visually

The Great Filter suggests that, the reason there has been no contact with advanced civilizations is for one of two reasons. Both explanations utilize the idea of a ‘great filter,’ or evolutionary hurdle that any civilization looking to advance past a certain point must overcome, and that rarely, if ever, does this happen. The thought process breaks down in two ways: either 1) we are a unique civilization in that humanity has crossed the filter and as a result are the most (or one of the most) advanced civilizations in the galaxy, or 2) we, among most or all other civilizations currently in existence in the galaxy, have yet to reach the filter, at which point we will face some insurmountable crisis that will in all odds most likely mean the end for humanity. These explanations solve the Fermi Paradox by suggesting that, yes, there were, are, and will be vast civilizations that populate our galaxy, but that inevitably, they reach a point in their advancement at which time they are wiped out, either through self-annihilation or external causes. Therefore, while there are countless civilizations out there, either none of them will advance to the point where they can communicate with us, or we will face our end as a species before we develop much farther.

The plausibility of the Great Filter leaves one with an existential dread in the recognition that our future as a species is bound for one of two paths: if we have yet to cross the filter, humanity is in all probability careening towards certain death. The alternative, while favorable in that we survive, leaves us in the far lonelier position as the only civilization likely to sufficiently advance to the point of traveling the stars.

Kurzgesagt_Great_Filter-1024x576

Featured image is a screenshot from the referenced video by Kurzgesagt

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Bringing Colonialism to Space

Posted on May 1, 2018 by Jeanie Zeng

“I’m certain success is one of the possible outcomes for establishing a self sustaining Mars colony, in fact a growing Mars colony. I’m certain that it’s possible.”  –Elon Musk

“I believe that the long-term future of the human race must be in space.”  –Stephen Hawking

“We want to go to space to save the Earth.”  –Jeff Bezos

Image result for space colonization cartoon
New world space colony

There’s a lot of hype about extraterrestrial colonization. Many of the biggest names in tech, science, and business have either personally invested in or attested to the importance of intergalactic expansion.

Mars, in particular, has received a significant amount of attention. It’s one of the closest bodies in the Solar System to Earth, contains water (although not liquid, as far as we know), and its atmosphere isn’t completely toxic to humans like Venus’s. High-profile companies and organizations like SpaceX and Mars One have already declared their extremely public intentions to establish a colony on Mars.

But what about the life on Mars that potentially exists there already? Scientists have not gathered enough conclusive evidence to determine whether or not life is present on the planet. If habitat-establishing technology, much less humans, were to traverse the world, it’s possible that we may contaminate and possibly even destroy the life forms that previously called the planet home.

It was for this very reason that the Cassini spacecraft was deliberately crashed into Saturn. NASA scientists used Cassini’s last bit of energy to intentionally enter into Saturn’s orbit and crash into the planet. The risk of Cassini drifting into and potentially contaminating one of Saturn’s potentially life-bearing moons was too great. Even at the peak of our excitement at exploring these unknown worlds, we recognized the importance of preserving other life forms and environments. In the same way that we have endangered species and protected area zones on Earth, these extraterrestrial bodies may also require our attention and deliberate conservation.

It’s a very humans-first mentality to decide to colonize a planet just because we can. And while the very notion of prioritizing the human race as a species seems obvious now with the microbial life forms we will most likely encounter, it will become an inherently more complex moral question down the road if and when we run into more evolved forms of life. After all, if we, ourselves, take this approach, we can also expect that another intergalactic species may feel justified in using this approach on us.

Image result for war of the worlds
An alien species colonizing a new world
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Life on the ISS

Posted on May 1, 2018 by Taylor Matalon

The construction and operation of the International Space Station is a crowning paragon of human achievement. Though it is such a grand and awe-inspiring system, I am often curious about the smaller, tedious details regarding life on the station for the astronauts and cosmonauts. I looked up some youtube videos and found some rather amusing and interesting facets. First, they sleep in sleeping bags that are secured to a wall, yet there’s no way to “lie down.” When the astronauts fall asleep, their arms rise above their heads and their bodies could be floating in the middle of their bunk. Brushing teeth is also interesting; water must be squeezed directly onto the toothbrush, and toothpaste and applied and then just swallowed (where else would it go?). Most of the inhabitants’ water supply comes from recycled pee (which is a rather sustainable closed-loop system). There is also workout equipment to make sure that the inhabitants do not lose their muscle and bone density from the weightlessness. They have a treadmill, a bike, and a lifting station. They are allowed personal items, such as action figures or guitars. Canadian astronaut Chris Hadfield even performed a cover of “Space Oddity” from the station!

 

Image result for chris hadfield space oddity

 

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MEET the home of E.T.?

Posted on May 1, 2018 by Jeanie Zeng

Liquid water, energy and organic material.

According to NASA’s director of planetary science, James Green, these are the major criteria needed for life to form.

Green and the rest of his NASA colleagues have also identified four extraterrestrial worlds in our Solar System that hold particular potential for the possibility of life. These worlds encompass one or more of the criteria that Green outlines is necessary for life.

Image result for mars europa titan enceladus
Worlds in the Solar System that are most likely to have life

Mars

The ancient riverbeds and deltas that have been found on Mars’s surface suggest that the trigger for life may have occurred sometime in the planet’s past. Although the only form of water on Mars currently are the polar ice caps, scientists believe that temperatures in the past may have been warm enough to allow for liquid water and thus, the development of microbial life. There’s even some evidence that the planet’s crust might contain traces of organic compounds.

Europa

While the surface of this moon of Jupiter is covered in ice, not liquid water, the lack of craters indicate that the ice is being smoothed over throughout time. Scientists think this could be due to a liquid water ocean underneath the surface. Further evidence can be found in the fractures of the surface ice and the liquid water jet streams shooting from holes in the ice, suggesting that there may be volcanic or tectonic activity. The heat generated from this activity may be just enough to support non-photosynthesizing life in the same way that geothermal vents on Earth’s ocean floor do.

Enceladus

Like Europa, Enceladus is of high interest to scientists for its potential undersurface ocean. This moon of Saturn also is covered in ice but the layer is slightly thinner. More promisingly, we have detected plumes of salty water vapor shooting from Enceladus’s south pole. In the vapor we have detected organic molecules, including carbon, nitrogen, and oxygen. The vapor plumes suggest a more powerful force at work, such as a liquid ocean. Additionally, the ejection and return of the plumes hint at the possibility of a water cycle that could circulate organic molecules over time.

Titan

Titan is extremely similar to Earth. The largest moon of Saturn has a similar surface pressure, atmospheric nitrogen composition, and geological features. It even has a chemically active atmosphere that is especially important for protecting life from extreme radiation. Instead of oxygen, Titan has an abundance of methane and ethane. Scientists think that it is possible that some organisms may have evolved to live in a hydrocarbon medium like that of Titan. There’s even a possibility that the abundant methane is due to life itself.

 

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The “Archaeological-Form” of the Drake Equation

Posted on May 1, 2018 by alcottastr2110

 

Drake equation U of Rochester

The Revised Equation

 

The Drake Equation is a very useful tool to speculate on one of the most intriguing questions of all time: are there other intelligent lifeforms out there in the universe? The equation helps to predict the odds of the existence of other civilizations. It is all still speculation, but recently two professors at the University of Rochester made some tweaks to the equation in order to show the low probability of us being the only civilizations in the universe. Adam Frank (one of the professors) mentions that we shouldn’t be necessarily trying to figure out if other intelligent lifeforms exist now, but rather if they have ever existed. Of course considering this makes the odds of other life much more likely. Frank estimates with his equation that if humanity is the only civilization to have ever developed in the universe, then the odds of a civilization developing on a habitable planet would be around 1 in 10 billion trillion. This is an unbelievably small number and it certainly makes an interesting case that people should operate under the assumption that we can’t be the only civilization to ever inhabit this universe. If their equation is used to only consider the odds of a civilization developing in the Milky Way, the odds of us being the only one is about 1 in 60 billion, another very small number. I find this very interesting to think about and it is truly amazing how unlikely it really is for us to be the only civilization in the universe ever. However, although it is exciting to talk about, I’m not sure all this speculation does much good at the moment. I’m much more interested in simply finding life of any sort somewhere else in the universe. Talking about the low probability of us being the only intelligent lifeforms seems like it is almost assuming that there are for sure at least some sort of unintelligent lifeforms out there. I understand that statistically it is not a ridiculous assumption to make, but we haven’t found life of any sort yet. That being said, it is still awesome to think about, it just feels like some might be getting a little ahead of themselves, we should just focus on any form of life first in my opinion.

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The “Archaeological-Form” of the Drake Equation

Posted on May 1, 2018 by alcottastr2110

 

Drake equation U of Rochester

The Revised Equation

 

The Drake Equation is a very useful tool to speculate on one of the most intriguing questions of all time: are there other intelligent lifeforms out there in the universe? The equation helps to predict the odds of the existence of other civilizations. It is all still speculation, but recently two professors at the University of Rochester made some tweaks to the equation in order to show the low probability of us being the only civilizations in the universe. Adam Frank (one of the professors) mentions that we shouldn’t be necessarily trying to figure out if other intelligent lifeforms exist now, but rather if they have ever existed. Of course considering this makes the odds of other life much more likely. Frank estimates with his equation that if humanity is the only civilization to have ever developed in the universe, then the odds of a civilization developing on a habitable planet would be around 1 in 10 billion trillion. This is an unbelievably small number and it certainly makes an interesting case that people should operate under the assumption that we can’t be the only civilization to ever inhabit this universe. If their equation is used to only consider the odds of a civilization developing in the Milky Way, the odds of us being the only one is about 1 in 60 billion, another very small number. I find this very interesting to think about and it is truly amazing how unlikely it really is for us to be the only civilization in the universe ever. However, although it is exciting to talk about, I’m not sure all this speculation does much good at the moment. I’m much more interested in simply finding life of any sort somewhere else in the universe. Talking about the low probability of us being the only intelligent lifeforms seems like it is almost assuming that there are for sure at least some sort of unintelligent lifeforms out there. I understand that statistically it is not a ridiculous assumption to make, but we haven’t found life of any sort yet. That being said, it is still awesome to think about, it just feels like some might be getting a little ahead of themselves, we should just focus on any form of life first in my opinion.

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The Great Filter

Posted on May 1, 2018 by Taylor Matalon

A lesser-known cousin of the Fermi Paradox is “The Great Filter.” The filter refers to a point in a species’ development that destroys most, if not all life. Essentially, the reason that the paradox exists must be because something is stopping other civilizations– all other civilizations. For us Earthlings, there are two possibilities: the filter is ahead of us; the filter is behind us. If the filter is behind us, then we have much to fear. We are going to face something that, so far, has destroyed all other lifeforms. If we were to discover plentiful alien life, then this would be even worse, confirming that we are not alone in our path to the filter. The better scenario is one in which we are past the Great Filter. This means that whatever challenge all other life has faced and failed, we prevailed. This could be the development of intelligence, the development of technology, anything. We may be the first civilization that defies the Fermi Paradox for other lifeforms. If we are past the filter, then we are the pioneers of technological advancement, and can hopefully help other species get past the filter as well.

 

Image result for the great filter

 

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Project Orion: Blasting Off to the Stars

Posted on May 1, 2018 by jacobfinesastroblog

In the late 1950’s and early 1960’s the US was in the midst of the cold war. At that point, the American space program had fallen far behind Soviet rocket technology. Desperate to upstage the Soviets, the US began to pour funding into seemingly crazy technological research. One of these projects being Project Orion.

orion

In essence, Project Orion aimed to blast a rocket into space by exploding nuclear bombs beneath the vessel.  Through the use of dense radiation shielding and shock distribution systems, the vessel would remain intact as it dropped a continuous flow of explosives behind it.  To this end, this type of rocket was theorized to be able to travel at a significant percentage (0.3-10%) of the speed of light. For this reason, the Project Orion was considered for use in long distance space travel.

 

Although a large scale nuclear blast propelled rocket could potentially function well on paper, a full scale design has never been tested due to several impracticalities. From an environmental standpoint, the launch of such a rocked would require the detonation of several nuclear warheads within the earth’s atmosphere. This would lead to localized radiation of the surrounding environment. From a engineering standpoint, the back plate of such a rocket would have to be able to withstand hundreds nuclear blasts while dampening the the shock of sudden acceleration. Historically, research into Project Orion was ceased after the Partial Test Ban of 1963, a measure to help ease tension in the cold war.

 

While a large scale nuclear propelled rocket has never been created, it remains to be one of the only propulsion systems capable of moving a sizable craft to significant fractions of the speed of light.

 

 

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Project Orion: Blasting Off to the Stars

Posted on May 1, 2018 by jacobfinesastroblog

In the late 1950’s and early 1960’s the US was in the midst of the cold war. At that point, the American space program had fallen far behind Soviet rocket technology. Desperate to upstage the Soviets, the US began to pour funding into seemingly crazy technological research. One of these projects being Project Orion.

orion

In essence, Project Orion aimed to blast a rocket into space by exploding nuclear bombs beneath the vessel.  Through the use of dense radiation shielding and shock distribution systems, the vessel would remain intact as it dropped a continuous flow of explosives behind it.  To this end, this type of rocket was theorized to be able to travel at a significant percentage (0.3-10%) of the speed of light. For this reason, the Project Orion was considered for use in long distance space travel.

 

Although a large scale nuclear blast propelled rocket could potentially function well on paper, a full scale design has never been tested due to several impracticalities. From an environmental standpoint, the launch of such a rocked would require the detonation of several nuclear warheads within the earth’s atmosphere. This would lead to localized radiation of the surrounding environment. From a engineering standpoint, the back plate of such a rocket would have to be able to withstand hundreds nuclear blasts while dampening the the shock of sudden acceleration. Historically, research into Project Orion was ceased after the Partial Test Ban of 1963, a measure to help ease tension in the cold war.

 

While a large scale nuclear propelled rocket has never been created, it remains to be one of the only propulsion systems capable of moving a sizable craft to significant fractions of the speed of light.

 

 

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