Black Hole Systems

Posted on May 4, 2022 by evang914

Stars are capable of being pulled into the orbit of black holes due to their incredible mass. As the stars begin to orbit the black hole, mass from the star is pulled towards the black hole in the form of gas from the star’s atmosphere. NASA believes that the black hole collects the mass as either a steady stream of gas flowing from the star to the black hole or from the star’s stellar wind being consumed by the black hole. The collected gas creates the swirling accretion disk of the black hole that glows in visible, ultraviolet, and x-ray light. Astronomers can use this light to understand the strength of the gravitational field and the mass of the object acting on the star, allowing them to make determinations about the existence of black holes.

NASA recently released a video visualization that displays 22 of these confirmed binary black hole systems in the Milky Way and Large Magellanic Cloud, a neighboring galaxy 160,000 light-years away. Some stars have an orbital period as low as a few hours, while others orbit a black hole 15x more massive than the sun. The teardrop-shaped excess from the stars represents the parasitic nature of the black hole stealing mass from its companion star. All systems shown are X-Ray binary systems, meaning that as the mass is falling from the star to the black hole, it releases gravitational potential energy in the form of X-Rays.

via NASA Goddard

Source: Gizmodo, Astronomy.com, Wikipedia

Posted in Class | Tagged , , | Comments Off on Black Hole Systems

The Myths of the Fermi Paradox

Posted on May 4, 2022 by evang914
Enrico Fermi, via Smithsonian Magazine

For decades, the Fermi Paradox has been cited as evidence that if other intelligent life existed out there in our universe they would have inevitably made their way to Earth by now as a part of interstellar exploration or colonization. The paradox is named for Enrico Fermi, the Nobel Prize-winning physicist credited with building the first nuclear reactor. The myth of the Fermi Paradox begins with Fermi himself; he had never made such a claim that aliens do not exist, nor published any materials about extraterrestrial life.

The story goes that at a lunch looking at a New Yorker cartoon of flying saucers in 1950, Fermi commented “Where is everybody?” in reference to the lack of cited alien ships. The discussion at that point turned towards the feasibility of interstellar space travel, with Fermi concluding its existence to be unlikely. He did not question the potential for ET life, however. Astronomer Michael Hart in the 1970s first jumped to the conclusion that if aliens aren’t here, then they aren’t anywhere. His argument was that if smart aliens existed they would inevitably colonize the milky way, but since they haven’t, we must be alone. Fermi’s question regarding the feasibility of interstellar travel mistakenly became engraved with the sentiment, and Hart’s leap of logic has been questioned many times by others.

The other myth of the Fermi Paradox is that it is even a paradox. Logical contradictions do not exist between the statements extraterrestrial life might exist elsewhere and extraterrestrial life does not exist on Earth. Regardless, Fermi’s Paradox has been cited as evidence against the funding of SETI projects. In 1981 a Senator from Wisconsin cited it as a reason for killing NASA’s SETI project. Although it was restarted for a few years, in 1993 it was killed again, and as of 2016, no new programs searching for life have been given government funds.

Source: Scientific American

Posted in Class | Tagged , , | Comments Off on The Myths of the Fermi Paradox

The Future of Space: Defense and Exploration

Posted on May 3, 2022 by Brian
The crew of the recent Axiom Space private mission to the ISS, another example of the private sector expanding into space travel

Our recent studies of impacts and life in the universe have made me consider the future of astronomy and space travel. The incessant threat of a catastrophic impact means that there will always be a focus on impactor defense here on Earth, and humanity’s natural urge for expansion and exploration will surely result in future innovation in space travel. In my opinion, two recent news stories about space and science have given us insight into what the future holds: constant interaction between space agencies, politics, militaries, and the private sector.

The first news story reports on a 2014 meteor that was suspected to be of interstellar origin. Researchers had relied on sensitive data from US military missile-detection satellites, however, and it was impossible to verify their claims without compromising classified US intelligence capabilities. In April, though, the US Space Command released a memo seemingly confirming that the meteor was an interstellar object. While this conclusion is still up for debate, I found it fascinating that the US military has unique access to such important astronomical data. Looking to the future, the article mentions that NASA and the US Space Force have agreed to collaborate on the issue of planetary defense. As Earth continues to build out its impactor defense capabilities and systems, it will be fascinating to see how these agencies interact and create a plan to save Earth from a potential threat.

The second story, about crowding on the ISS, reveals more about the intersection of space travel, politics, and the private sector. Fueled by innovations by SpaceX, space travel has become cheaper and more common, pushing our older infrastructure like the ISS to its limits. In the near future, Boeing’s Starliner spacecraft will be rotated into use alongside SpaceX rockets by NASA, signaling even more growth in the business of space travel. Space travel has also become more accessible to amateur astronauts: one group on the ISS at the time was a private trip run by Axiom Space. Furthermore, the United States and Russia renewed their agreement to jointly administer the ISS, showing how cooperation in space can transcend political tension on Earth. As space travel becomes more frequent and transitions into a joint private-public venture in the near future, I will be watching to see how cosmic priorities align with or compete with terrestrial objectives.

We are living in an incredibly active time of progress both for Earth-focused astronomy and space exploration, and if humanity wants to achieve its lofty goals on both fronts, there will need to be significant interaction between space programs, private businesses, the armed forces, and politics.

Posted in Class, Public Policy, Space Travel | Tagged , , | Comments Off on The Future of Space: Defense and Exploration

Fermi Paradox Answered?! (not clickbait)

Posted on May 3, 2022 by alexbawa

After hastily copy pasting “Fermi Paradox” into my search bar when I saw it was a potential topic for blogging, the results I found gave me an exciting opportunity. Understanding why we haven’t detected aliens seemed right up the alley of Kurzgesagt, a youtube channel that specializes in the intersection of physics and philosophy. Luckily for me, the channel had not one, but two videos on the subject.

The Fermi Paradox questions why we haven’t detected any life outside of Earth, especially if the Cosmological Principle holds. Given that the universe is homogenous and infinite, it doesn’t make sense for Earth to be the only host of life. This provides two trains of thought: we are actually a special case, or we just aren’t equipped to detect other life that shares our time in the universe. Given that much of astronomy is built on our solar system not being the favorite child, I don’t buy too deeply into the former. The latter, however, sparks some exciting conversation.

Primarily, it’s possible that intelligent life has existed (a lot), but they died off before we were ready to have any chance of realizing they were there. The videos suggest that there are barriers that our society has yet to meet that may have killed off other civilizations.

Kurzgesagt visualization of civilization barriers

Given that these challenges likely follow advanced communication ability relatively quickly, the window for opportunity is slim. That being said, it’s also possible that we still don’t have the technology to communicate in the ways we need to, even if there are other inhabitants in our universe.

Posted in Universe | Tagged , , | Comments Off on Fermi Paradox Answered?! (not clickbait)

Extremophiles: The Deinococcus Radiodurans

Posted on May 3, 2022 by Sheila Chau

Extremophiles are organisms that live in extreme environments; these environments are usually under high pressure and temperature. These organisms use certain enzymes, ‘extremozymes’, that help them exist in such an intense environment.

Extremophiles were more prominent in the evolutionary history of the planet. They date back to more than 40 million years ago, and they continue to flourish in these intense environments.

The Deinococcus Radioduran

The most common extremophile is Deinococcus radiodurans. This is one of the most radiation-resistant organisms known. It can withstand the cold, acid, and dehydration, making it a polyextremophile. It can survive high levels of ionizing radiation. In the Guinness Book of World Records, it’s the strongest known bacterium in the world.

Posted in Class | Tagged , | Comments Off on Extremophiles: The Deinococcus Radiodurans

Fermi’s Paradox

Posted on May 3, 2022 by Sheila Chau

Fermi’s paradox is the paradox where is there is no clear evidence for extraterrestrial life. This paradox was named after physicist Enrico Fermi, who made the point that we hadn’t seen any extraterrestrials. Where is everybody else? The Fermi paradox has possible solutions that are split into 3 categories: we are alone; civilizations are common, but no one has colonized the galaxy; and galactic civilizations exist, but it has not been revealed to us yet.

The first solution is the scariest to me; I hate the idea that we are truly alone. It would make for our society to be an extreme accomplishment, but it would also make for a tragic future when our civilization collapses.

The second solution is also scary because it indicates less hope in our civilization achieving interstellar travel. What happened to other civilizations may happen to ours’. What does this mean for us?

The third solution is the most hopeful. This is also, personally, the solution is believe the most in. The universe is too vast and untravelled for there to only be us existing.

Where is everyone else?

Posted in Class | Tagged , , | Comments Off on Fermi’s Paradox

Where are all the Aliens? Natural and Self-Inflicted Explanations for the Fermi Paradox

Posted on May 3, 2022 by Brian
If climate change is a generic process that affects all highly developed civilizations, it could be one of the most compelling explanations of the Fermi Paradox

Broadly speaking, our views on the probability of extraterrestrial life have gotten more optimistic over time due to a long series of discoveries that have increased our estimates for the size of the universe, the frequency of planets, the frequency of liquid water on worlds, and the ability for life to thrive in extreme conditions. This only makes the Fermi paradox more paradoxical— where are all the aliens?

Our textbook groups solutions into three major categories: we are alone, civilizations exist but have not colonized the galaxy, and existing civilizations have not revealed themselves to us. I find category two to be the most compelling. It is hard for me to believe that there are no alien civilizations out there, and I find explanation three to be conspiratorial and far-fetched. I imagine that it is difficult for civilizations to last long enough to achieve interstellar capabilities, due to natural and self-inflicted processes. 

As the Wikipedia article for the Fermi paradox states, many natural extinction events have occurred on Earth, caused by volcanic eruptions, giant impacts, and maybe even gamma ray bursts. Although these events have been relatively infrequent on Earth, it would take far less than an existential-level threat to wipe out or significantly set back an otherwise “galactic” civilization. Perhaps this magnitude of natural event is frequent enough to limit the lifespans of galactic civilizations enough to prevent them from realizing their potential.

It is also possible that civilizations destroy themselves before they can colonize the Galaxy. Once a civilization discovers nuclear weapons—which is nearly if not necessarily a prerequisite for galactic capabilities—the odds of self-inflicted extinction rise several orders of magnitude. Combining both natural and self-inflicted processes, climate change is a particularly interesting aspect of this issue. A 2018 interview with astrophysicist Adam Frank explores the process of climate change as a symptom of the Anthropocene transition and views both through an astrobiological lens. Frank posits that perhaps every technologically developed, energy-dependent civilization drives significant change in their planet and its climate. While his initial theories did find steady states, where a civilization does not destroy its planet and itself, there is a real possibility that a galactic level civilization places a very restrictive time limit on itself through self-inflicted climate change and planetary transition.

As we progress through our own Anthropocene transition, we will undoubtedly learn more about potential lifespans for intelligent civilizations. Hopefully, humanity achieves one of Frank’s steady states and lasts long enough to make contact with other forms of life.

Posted in Aliens, Class | Tagged , , | Comments Off on Where are all the Aliens? Natural and Self-Inflicted Explanations for the Fermi Paradox

The Future of Space Travel – The Skyhook

Posted on May 2, 2022 by Johann West

Infrastructure is everywhere. Most every way of transport that we consider using regularly has immense infrastructure. Cars have roads, trains have rails and stations, and airplanes have airports and runways. But with space travel, we take the brute force method, spending immense amounts of money and forcing a rocket to defy gravity and get itself into orbit. Organizations like SpaceX are currently trying to remedy some of the issues with this, with reusable rockets and other new technologies, but there is one technology that could massively accelerate the feasibility of space travel, the Skyhook

The Skyhook is a simple mechanism, basically consisting of a cable and a counterweight, placed in orbit. The concept of its use is as follows. A spacecraft would have to reach a height of 80-150 km by itself in order to attach to the Skyhook cable, and then the rotational force of the Skyhook would swing the spacecraft into space like a catapult, as shown below.

Photos Source

Of course like any technology there are hurdles to overcome, even though 150 km is much easier to reach than breaking a low orbit of say 1000 km, that is still quite a height to get to, and would require the invention of a new craft that is something of an airplane rocket hybrid. However, it still should be much cheaper, especially if these craft are reusable. Additionally, the Skyhook would not be able to be used permanently because every time it flings a spacecraft into space it would lose a little bit of altitude itself. There are many other potential obstacles, but in my opinion, none that are improbable or outweigh the potential benefits of eliminating the modern wasteful rocket.

Sources:

1,000km Cable to the Stars – The Skyhook

Categories:

, ,

Tags:

, , ,
Posted in Space Travel | Tagged , , , , , , | Comments Off on The Future of Space Travel – The Skyhook

The Fermi Paradox : Are We Alone?

Posted on May 2, 2022 by Johann West

The Fermi Paradox Picture

The universe is magnificently huge, and hence should have countless opportunities for life to develop, but that then begs the question, where are all the aliens? Due to the expansion of the universe being faster than the speed of life, there may be life throughout many galaxies, or even most of them, but we would simply never really know for sure do to any signal sent being outpaced in speed by the expansion of the universe, at least with our current understanding of physics. So it is practically pointless to search for life outside of our galaxy, so then where are all the Milky Way aliens? Even narrowing our search area to just 1 of 100 billion galaxies, there still should be ample opportunities for life to develop in our galaxy, where communication, however still improbable, is possible. Different studies estimate there are anywhere between 300 million to 6 billion Earth-like habitable planets in the milky way, so what gives?

There are many theories as to why life seems to be missing from the Milky Way. Perhaps they are in hiding, and only the silent civilizations survive. Perhaps they have all died out, and we simply live in a time where no other near type 1 or type 2 civilizations exist alongside is. Perhaps we are the first, pioneering the concept of intelligent life. Or perhaps billions of chances for life simply is not that many if we truly knew how complicated and rare life developing is, and we sincerely are special in this galaxy. Only time and technology will tell.

Sources:

The Fermi Paradox Video

bbvaopenmind

, , , ,
, , ,
Posted in Class, Galaxies, Space Travel | Tagged , , , , , , , | Comments Off on The Fermi Paradox : Are We Alone?

The Egg

Posted on May 2, 2022 by jordanekstein

A man named Andy Weir, created an idea of life and the universe called, The Egg. The story starts out with a man dying in a car crash and coming face to face with what seems to be God. Immediately this person begins asking about their family and the life they left behind along with what happens next. The large being before him tells him not to worry and that he is going to be reincarnated as a girl from 540 AD. Puzzled the man does not understand how he can become someone from the past, someone that must have already existed if he lived past that date. The being explains that time is merely a physical concept. The man then ponders if he could have been reincarnated at a time when another version of himself was living. The being nods and says that this is true. Finally, the being explains that the whole universe was made to be a growing and maturing experience for the man and he will be and has been every person who has ever existed. He learns and grows through interacting with himself as every person is a version of himself. This universe is essentially, an egg, a place for this being to grow to become like the larger being and one day be what we consider a God. Some see this as a real theory of life! While others just think it is a nice way to say we are all connected and all of our actions affect others in ways that ultimately affect ourselves.

Posted in Aliens | Tagged , | Comments Off on The Egg