The Death Star

Posted on April 10, 2021 by brianknapp

Saturn is the mooniest planet in our Solar System, with us having discovered over 80 of them. While many moons have interesting features, only one of them look like they could destroy Alderaan. Say hello to the moon Mimas, which as you may notice, looks a bit familiar.

Mimas compared to the Death Star

That’s right, Mimas look like the Death Star from Star Wars. While the entire surface of the moon is riddled with craters (meaning the world is quite old), the 80 mile diameter Herschel Crater is without a doubt its most defining feature. It is thought that the impactor responsible for this crater nearly tore the world apart. In fact, there are fractures on the opposite side of the surface, demonstrating the intensity of the impact. The myriad of craters also implies the world to be frozen, which is a bit puzzling, as the position of the moon suggests to scientists that there would be a great bit of tidal heating, which would result in a warmer world. This paradox has led to the “Mimas Test,” which requires that any theory that explains the partially thawed water of the moon Enceladus (a moon near Mimas) must also explain the entirely frozen water of Mimas. The exact reason for the conditions of Mimas are still unclear, but as you may know, the dark side of the Force is a pathway to many abilities some consider to be unnatural…

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Caroline Herschel

Posted on April 10, 2021 by wendyyb

Many are familiar with William Herschel, the man accredited with discovering Uranus, but lesser known is his sister: Caroline Herschel. Born March 16, 1750, Caroline Herschel was the first female professional astronomer. Growing up, Caroline’s mother did not support Caroline’s pursuit of an education. As a result, Caroline largely relied on her brother to learn math, science, and other academic subjects. Using this knowledge, Caroline went on to become the first woman to discover a comet (1786). In addition to her comet discovery, within her lifetime she also catalogued 560 stars and 2,500 nebulae. She also played a significant role in aiding with William’s calculations that led to discovery of Uranus. Despite this, she is often left out of acknowledgements. At age 77, she was awarded a gold medal from the Astronomical society.

Caroline Herschel - Wikipedia
A portrait of Caroline Herschel, via Wikipedia

Some lesser known details about Caroline include that she never grew past 4’3″ due to getting typhus at age 10. Additionally, her and her brother worked as musicians before becoming involved with astronomy. Despite such significant contributions to science, as with many other historical female figures, she is often left out of textbooks due to her status as “not a white male”. Have you previously heard of Caroline Herschel? In what ways does overlooking female scientists affect us today?

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The Death of Cassini

Posted on April 9, 2021 by brianknapp

The Cassini Spacecraft was designed to explore Saturn and its many rings and moons. It launched from Earth in 1997, beginning its 7-year journey to the outer solar system. Upon arrival, it released the Huygens Probe – the first object of our own creation to land in the outer solar system. This probe landed on Saturn’s moon Titan, and along with Cassini revealed the presence of bodies of liquid methane on its surface. Cassini had been providing us with astonishing discoveries like this for more than 10 years. In 2017, it finally ran out of energy, but had enough left for one grand finale.

Saturn, by Cassini

Cassini’s final task was a series of over 20 dives through space between Saturn and its rings – a never before explored region. These dives allowed for scientists to uncover several new pieces of information, including the age of Saturn’s relatively young rings. It is estimated they were formed around 10-100 million years ago, which means they could have formed when dinosaurs walked the Earth. After this, Cassini was ready to end.

To avoid possible contamination of Saturn’s moons, Cassini was sent into the surface of Saturn to be destroyed. On its final orbit, September 15th, 2017, Cassini flew into the planet, pointing its antenna back towards Earth to give us its final transmission before becoming part of Saturn itself. A beautiful end to a historic mission.

The Death of Cassini, Artist’s Concept
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Meteorites

Posted on April 8, 2021 by ben141414
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Meteorites are fascinating. As we learned in class, a meteor is a flash of light caused by a particle of dust or rock entering Earth’s atmosphere at a high speed. But, a meteorite is a meteor that survives its drop through the atmosphere and reaches Earth’s surface. In terms of discovering meteorites, there is a subtle distinction in the language, similar to that of meteor vs. meteorite. Meteorite falls are meteorites that are collected soon after the fall is witnessed, while meteorite finds are those rocks that are discovered at a later time. Ernst Chladni was a German physicist who is referred to by some as the father of meteoritics because he was the first in modern times to publish his idea that meteorites are rocks from space (in 1794). Prior to Chladni’s modern theory, there had been loose documentation of meteorite falls. One of the most ancient records of a meteorite fall was the Aegospotami meteorite in 467 BC. Nowadays, there are usually around half a dozen falls annually. Meteorites are commonly categorized by material: iron meteorites (around 4.4% of discovered meteorites), stony-iron meteorites (around 1% of discovered meteorites), and stony meteorites (around 94.6% of discovered meteorites). Finally, I’ll leave y’all with some sources to explore meteorites. This Wikipedia page has a record of many meteorite falls. This database, from The Meteoritical Society, has a search feature that allows you to filter for various variables and search for meteorites. And this is a three-minute video of some really cool meteorite falls. Drop some more links below in the comments if you find any on your own!

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Enceladus got life?

Posted on April 5, 2021 by yvan247
Flying Through the Plume on Saturn's Moon Enceladus ...
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Thanks NASA’s Cassini mission, scientists have been able to confirm that underneath the icy crust of one of Saturn’s moons, Enceladus, lies a global ocean. Naturally, that begs the question could there possibly be something living in that ocean. When looking for life in our solar system, the first thing we look for is water (H2O). That is the most important element that has to be present and if we find it, we know we are on the right track.

Now when it comes to Enceladus, not only did we find some water, we essentially found an entire planet full of it. But even though water is a great place to start, it doesn’t guarantee life, especially after you consider that Enceladus is so far away from the sun that sunlight doesn’t reach it making photosynthesis impossible, and there is also no oxygen on Saturn’s moon. After factoring all of that, the whole life on Enceladus thing isn’t looking too good. But what if we can find examples of life thriving is the most exotic and desolate parts of Earth? That’s where there’s hope.

Scientists have discovered microbes in parts of our planet where sunlight doesn’t reach, and oxygen isn’t present because photosynthesis can’t take place. Sound familiar? There are three ecosystem here on Earth that could be the basis for life on Saturn’s moon—two of them are based on methanogens, that belongs to an ancient bacterial group related to the “rugged survivalists” archaea. These are found in volcanic rocks along the Colombian river as well as in Idaho Falls, so they are real! These microbes pull their energy form the chemical interactions of different rocks, while the microbes in third ecosystem located deep within a South African mine, gets energy from radioactive decay in rocks. This is how we know life is feasible on Enceladus, but how would life start.

This is the trickier question to answer because we don’t even know exactly how life started on Earth. But what we do have our theories of how life originated on Earth and we can see which of those theories are applicable to Enchiladas. There are currently two theories that meet this criteria, the Primordial Soup theory and the Deep Sea Vent theory. But there are still more pieces of to this puzzle that we need to have a definitive answer, including analyzing the organic compounds in the plumes released by Enceladus’ aquifers and figuring out what is the energy source powering its aquifers. It looks like we are really close to the answer, and even if we find that life most likely isn’t present on Enceladus, that journey to that answer was definitely a fun one.

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Becoming One with Saturn

Posted on April 5, 2021 by yvan247
Cassini prepares to graze Saturn's rings - SpaceFlight Insider
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On September 17, 2017, NASA’s Cassini’s spacecraft exhausted its fuel supply. This marked the end of a 20 yearlong space exploration and 13 yearlong orbit around The planet Saturn.

The Cassini Mission was monumental in more ways than one. It was the first spacecraft to orbit Saturn, first to land in the outer solar system, and first to sample and extraterrestrial ocean. Because of Cassini, we discovered how Earth-like the moon Titan is and encouraged us to explore it further giving us insight to our own planet. Its long mission let us observer seasonal and weather changes on other planets, its close orbit to Saturn shed light on the complexities of Saturn’s rings.

At the end of its life, Cassini had travelled a total of 4.9 billion miles, captured 645 GB of data along with 453,048 images, and thanks to it, we discovered 6 additional moons.

What the Cassini mission did for science as a whole is endless. To attempt to list them all would be doing a disservice so here is the website dedicated entirely to the Cassini mission as a a beautiful short film about its journey.

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The Cleanest Place on Earth

Posted on April 5, 2021 by yvan247

NASA's MMS Team Assembles Final Observatory | NASA
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While working with or assembling new instruments or components used for space travel , NASA engineers and scientists must make their way to the clean room where they will give satellites and spacecrafts a final inspection before they can be launched into space. As the name suggests this room has to be free of any particles or dust that could disrupt the the sensitive equipment being used or contaminate the spacecraft itself. Clean rooms were first built in 1961 to support to support NASA’s Ranger and Mariner mission to the Moon, Venus, and Mars.

Now, I’m going put you in the shoes a NASA engineer on their way to the clean room. Close your eyes and imag… wait…no don’t close your eyes, you’re reading.

You’re standing in front of a door. You open it and walk in to see the floor covered in with white sticky matts and a shoe cleaner out of the corner of your eye. You stick one foot at a time in the shoe vacuum as it takes 5 seconds to a preliminary dirt removing. Next you start walking on the matts, feeling like someone spilled honey all over the floor, to get rid of even more outside gunk that your shoes are carrying. Congratulations! you made it passed the first set of “lobbies” on your way to the clean room. You have a couple more.

Now you’re standing in front of a phone-booth sized glass box. This is where you will take a quick shower. The walls inside the glass box are lined with jets that starts to blast you with air, “washing” away any debris left in your hair, skin, and clothing. You then notice a green light glowing indicating that you shower is done, allowing you to enter the last station.

You are surrounded by lockers and benches preparing yourself for the most painstaking step of the process. You spend the next 15 minute meticulously dressing yourself in a white, full body, sterile hazmat-like suit, glove, head covering, boots, and facemask. This is the end of the tunnel, so you don’t want to negate all the cleaning you gone through by rushing this process.

Now you’re all dressed and after giving yourself a pat on the back, you open the door to the clean room where you continue to be a part of history.

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The Iron Catastrophe

Posted on April 5, 2021 by yvan247

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Many believe that under the Earth’s crust, deep within the center of our planet, lies a molten core of iron and nickel responsible for heating up the earth’s and being the source for the lava that flows form our volcanoes. This is an understandable misconception as the temperature of the core of the earth rivals that of the surface of the sun. It’s hard to imagine anything not melting on the sun! Well I’m here to tell you that this is exactly what is happening with the Earth’s core.

YES! the Earth’s core is solid metal ball of iron and nickel.

But there is a story to why our metal core is able to remain solid with temperatures beyond the boiling point of any metal. It all starts 500 million years into the Earth’s lifespan with an event called “The Iron Catastrophe.” Back when the earth was forming, all of the heat and radioactivity from various material colliding and smashing into each other increased. The resulting collisions made the infant Earth so hot that all of the materials melted creating a squishy and gooey sphere. When earth was in this liquid state, due to gravity, all of the iron and nickel began to contract and compact towards the center of the planet where it began to cool.

But this still doesn’t explain why it remains solid despite being around 6,000 degrees Celsius. Well that’s because the pressure at the core of the Earth is so great that it essentially raises the melting point of the iron-nickel core beyond hat it normally should be.

As a result of the Iron Catastrophe, Earth’s magnetosphere formed creating a protective layer that reduces the harm of solar radiation and solar wind here on the surface of the earth.

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What Exactly is a Supernova?

Posted on March 30, 2021 by miichellewang
Image Source

To put it simply, supernovas are explosions of stars. They are the largest explosions that occur in our universe.

There are actually two ways that supernovas can occur. The first way happens at the end of a star’s lifetime. Stars are able to get their energy through nuclear fusion, which is when two atoms combine to form a new atom. When this energy runs out, there are two different outcomes depending on the mass of the star. The mass that separates these two outcomes is called the Chandrasekhar limit. If the mass of the star is below this limit, the star becomes a white dwarf. If it is above, the core of the star collapses onto itself and releases an extremely large amount of energy, forming either a neutron star or a black hole. Although the majority of this energy is released through invisible particles called neutrinos, the rest of the energy shoots out the outer areas of the star, producing a supernova. The second way only occurs in binary star systems when a white dwarf explodes. When two stars orbit the same point, they are described as binary stars. If the two stars collide or one star takes too much matter from the other, the star can explode and form a supernova.

Stars are mostly composed of hydrogen and helium, but nuclear fusion is able to produce much heavier elements. Supernovas then help distribute these elements from the stars’ cores to the rest of the universe, giving us the life we have today!

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Commercial Space Travel?

Posted on March 27, 2021 by zhengjs1
Space X Crew Dragon Capsule (Source)

Have you ever thought about traveling to space? While we’re far from intergalactical travel and settlements on other planets, space tourism and commercial space flights are closer to reality than ever before. A year ago, humans were able to access space through a non-government funded space vehicle for the first time in history under Space X, a private corporation with its main goal being affordable space settlement. The Space X Crew Dragon capsule was able to bring two NASA astronauts safely back to Earth from the International Space Station (ISS). Before this feat, the Russian Space Agency was the only company that had offered orbital space flights to the public, with a record of bringing seven tourists to space in the early 2000s before ceasing operations around a decade ago. Now, a few companies have built a solid foundation and are aiming to make the once far-away dream of public space flights a reality. Two private corporations, Virgin Galactic and Blue Origin, have set their eyes on commercial suborbital space flights. These flights travel at speeds slower than those required of orbital flights, but still provide its passengers a few minutes of weightlessness. Space X, most likely the leading corporation in private space exploration, have set its eyes on settling Mars and the Moon, but have also already sold seats on future Crew Dragon flights to wealthy customers. Lastly, an aerospace company named Boeing is right behind Space X in ferrying astronauts to the ISS, and is possibly looking at the ability to fly private passengers into space at a rate of $35,000 per night. While affordable commercial space flights are still not a thing, drastic development have taken place in recent years. With these corporations leading the future of space tourism, who knows? You might soon be able to view the stars and planets from Space!

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