Jupiter has a total of 53 named moons. That is more than any other planet in our solar system. The four largest moons ( Io, Europa, Callisto, and Ganymede) are called the Galilean Satellites. They were named after the astronomer Galileo who first discovered them. These four each have distinct characteristics that distinguish them from one another. Io, for example, has more volcanoes/volcanic activity than any other body in our solar system. Europa is an ice world that is said have have twice as much water as Earth. Ganymede is the largest moon in our solar system and is even larger than the planet mercury. Jupiter’s moons are extremely fascinating and even more fascinating to look at. Check out these beautiful shots from Nasa, and take a trip to their page on Jupiter’s moons for more info!
One thing that I think is going to stick with me the most is how cools moons are. Entering this class all I knew was our moon, and although that’s our girl, been here since day one, she’s pretty basic (no offense Luna, I still love you). So, I though all moons were like her, grey, small, round and, craters. I couldn’t have been more wrong. The fact that some moons maybe more suitable for life than any other planet of our solar system is mind boggling to me. Human could potentially relocate and repopulate on a moon! They are also some of the most aesthetically pleasing and intriguing objects in our solar system—Europa with its caramel drizzle like cracks and IO with bright yellow hue. If anyone taking this class in the future asks me what to expect from this course, I will be sure to let them know that they should expect to be shocked at how cool the moons of our solar system truly are.
I would like to introduce you to the Snottite. The Snottite is a microbial mat of extremophilic bacteria that hang around walls and ceiling of caves just like stalactites. That’s maybe why they have the same suffix. But yes, it does get its name for its mucus like consistency but they are every bit extremophile. Among other kinds of environments, the bacteria colony survive in very toxic and acidic environments. Their source of survival is a mechanism called chemosynthesis. Essentially, they turn volcanic sulfur compounds into energy and sulfuric acid waste that has similar property to that of battery acid. It’s safe to say that the Snottite’s dream world is IO, all the volcanic sulfur you could ever possibly dream of. They would be in paradise. we know that if there is life on other planets, it would most likely be in the more of an extremophile made for the conditions of that particular world. I think I just found what could be possibly existing on IO.
The likelihood of life outside of our planet is a heavily debated topic. Overall, it seems reasonable to assume that with all of the unexplored universe around us, and the conditions required to sustain life that are not all that hard to find, there should be plenty examples of life elsewhere. Despite this, and the overwhelming belief that we should be finding life, we are not. There is no evidence of any life, whether intelligent or not, outside of our planet. One explanation of this is the Fermi Paradox. It attempts to answer the question: where are the aliens? The Fermi Paradox proposes four arguments to explain the reason that we have not observed extraterrestrial life. 1: Aliens have not come to Earth due to the difficulty of space travel, whether it be from biological, astronomical or engineering difficulties. 2: Aliens simply have chosen never to come to Earth. 3: Advanced civilizations of aliens have arisen too recently for them to have been able to reach us yet. 4: Aliens have visited Earth in the past but for whatever reason, we did not observe them. This paradox does do a good job of attempting to answer a very perplexing question. That being said, most of these answers are quite unsettling as well. Personally, I think it would be very strange if aliens have been observing us, or have even come to our planet, and we have had no idea. I wonder which of these explanations, if any, are correct: let me know what you think is the most likely option!
It’s weird to think about how this will be the final assignment for our astronomy class. Throughout the semester, my understanding of the vast universe we exist in has deepened, further changing my perspective of our world and humanity’s role within it. In this class, we studied the basic processes of the universe, from its formation to the geographic and atmospheric processes of planetary bodies. I think one of the hardest concepts to understand or rather accept was the vastness of our universe. It is always said that the universe is massive, infinite, and further expanding, however, I don’t think I fully understood how true those concepts were before this class. It’s hard to understand the scale of the universe from our positions on earth. We considered location changes over states or countries as large measures of distance, so it is truly jarring when faced with the infinitely larger scale that the universe plays out on. This is true with both distance and time. The distance of planets, stars, and galaxies to Earth all exposed the vastness of the universe, however, the increment of time that humanity has existed within it is also incredibly small. In class, we looked at the Cosmic Calendar which maps the formation and development of the universe, and within this calendar, humanity is only present for a few seconds of the last day.
My perspective on life outside of Earth also changed. I always somewhat believed that somewhere within the universe there would be other life forms, however, now I truly understand that this is almost a certainty. When you think about the crazy number of stars within our universe and how common planetary bodies are that orbit these stars it is almost impossible not to believe in extraterrestrial life. Not to mention that even within our solar system there is still a possibility for life to exist on a few different worlds, like Europa, Io, or Titan.
Here’s a way to detect exoplanets you may have not heard of before! Microlensing is a technique that looks at how light is bent in the gravitational field surrounding a planetary system passing its star. The refraction creates “distorted, multiple, and/or brightened images.” All of these images are combined into one image. This image’s brightness is then analyzed as a function of the projected separation of the source and lens on the observer’s sky.
The advantages of microlensing are that it is more sensitive than existing techniques to discover small-mass planets like Earth. Microlensing is a useful technique for detecting planetary systems similar to those in our own Solar System. On the other hand, the technique requires heavy and intense use of telescope time that observatories may not be able to grant or guarantee, so microlensing does not work well for studying individual exoplanets.
The Fermi Paradox is a baffling observation about the galaxy and extraterrestrial life. The paradox asks, given all of the plausible explanations and arguments for the abundance of life in the universe, why haven’t we encountered signs of such life yet? With a self-replicating automatons and “modest amount of rocket power and an immodest desire to colonize the universe,” a type I civilization (which we are nearest to) should be able to colonize the entire galaxy in under 4 million years, a mere 0.0074% the age of the Milky Way itself.
There are three leading possible solutions to the Paradox. The leading explanation is the Great Filter idea. This is the notion that life passes through “filters” or critical events in the development of civilizations that only certain groups of life are fit to make it through. We are alone in the galaxy and the universe because we passed a filter no other extraterrestrial life form was able to pass. Another possibility with the Great Filter explanation is that we are on the way to a filter no life form can pass, which many of our predecessors reached countless years before we did, giving off the impression that we are alone in the universe.
Another idea is that we are on levels so different from one another–we being us and aliens–that it’s literally impossible to communicate. Perhaps the signals are being sent out but they are just so beyond our comprehension that they remain wholly undetectable by us.
The final proposition involves the matrioshka brain, the computational capacity to harness the complete energy of a star. A society this powerful may never feel the need to colonize and explore as a spacefaring society, because they have all the resources they already need. Thus, they remain undetected.
The leading solutions to the Fermi Paradox have a common denominator: we don’t know where the limits of technology lie. If we are approaching the end of its potential, then it is very unlikely that we could reach the technological stage needed in order for these solutions to be feasible. But if we’re only at the tip of the iceberg, then Fermi’s Paradox will continue to be something astronomers and enthusiasts ponder.
One of the biggest indicators that there is other life in the universe we can see by looking at our own world. All around us, in some of the most unexpected places, we can find thriving extremophiles. These tiny creatures live under conditions that no other living beings on Earth could. Despite their seemingly odd love of intense environments, these organisms are quite fascinating. Here is one of the coolest! Tardigrades are polyextremophiles. This means that they can thrive under multiple harsh conditions. They are able to withstand temperatures from -328 degrees F all the way up to 304 degrees F. Additionally, they can live without water and oxygen, in “boiling alcohol,” and under a thousand times the radiation humans can withstand. In order to live under such severe conditions, these creatures had to learn to adapt. One method of survival is going into cryptobiosis. This is a state in which bodily functions will shut down and the tardigrade will shrink, being called a “tun,” until conditions become a bit more habitable. In addition to being able to survive such extreme environments, these creatures win the award for cutest extremophile. Even though they are only a millimeter long, these little guys are fairly adorable. They are even nicknamed “water bear!”
The Northern Lights are one of the most intriguing phenomena of the natural world, and have been attributed to many different things throughout history. The name itself comes from Galileo, who names them after the Roman goddess Aurora, who in Greek was known as Eos and described as rosy-fingered. Many cultures have their own interpretations of the origins of the Northern Lights, with some native cultures saying it is where reindeer originate, and some Scandinavian ones saying it was an indication from god of Winter Ulr on the longest nights of the year. Reports of these lights have been around for at least centuries, with some interpreting cave drawings as depictions of flames in the air, denoting the lights. While these explanations are more fitting of the beauty of these lights, the real one is one rooted more in chemistry than divine intervention. They occur when material from solar flares interact with our magnetic field, which prompts certain particles of the atmosphere to release photons of light. Though not beautiful in the traditional sense, this, to me, is a very cool happening worthy of the same praise. It is literally the Sun’s ejection disturbing our magnetic field and results in one of the most beautiful sights on Earth.
I’ll begin this post by warning that it’s going to be a rather frank conversation about some mental health stuff. Nothing concerning or whatever, but I thought I’d put that out front.
Throughout this semester, I have struggled with my mental health. For me, this is mostly in the form of OCD, particularly obsessive thought patterns. This means that I get ideas or worries stuck in my head and they sort of loop through my mind constantly. A large part of these thought patterns had to do with the idea of existence. Sounds cliché, but I was essentially going through something of an existential crisis. The meaning of life, the cause behind everything, what truth was. I couldn’t escape these thoughts and worries about what everything meant.
But as part of astronomy, I was constantly reminded of how grand the universe truly was. In everything looked at, there was a startling, overwhelming beauty and grandeur. From the planets and moons in our solar system, all wonderfully unique and breathtaking in their own ways, to the massive stretches of stars and galaxies that spread infinitely beyond us. It makes one feel small, in a way, but it’s a good kind of small. That no matter what happens to you, or the people around you, or whatever the point may all be – there is so much beauty and wonder to be had, as far as we can see. Each little glimpse we get into the expanse beyond our planet is an expression of majesty and truth. In this way, our study of the sky ironically grounded me here on Earth. The infinite is so much greater than me and my worries, and who cares if it is cold and indifferent, unknowing of my existence? It is a gift to just be present and be able to gaze upon its beauty at all.