Blog 7—The Greenland Shark

Posted on May 4, 2021 by zvrec

In this blog post, I would like to introduce one of the species on Earth with some extreme characteristics. I think its existence is an extension to the concept of life in our common sense.


Greenland Shark

Somniosus microcephalus, also called the Greenland shark, or grey shark. They can reach a maximum length of 7 meters, which is comparable to the length of the great white shark. The Greenland sharks live in the North, mostly in the deep waters of the North Arctic Ocean and Antarctic Ocean. They are “lazy.” In most cases of being observed, they swim slowly, wandering on the surface of the seabed. Due to this famous characteristic, in our language, the Greenland sharks gained a nickname, the sleepy shark.

In the last couple minutes of the last dive of the field season we found the largest fish we have ever encountered with the ROV, a Greenland Shark.

However, the general features mentioned above are not what impressed people the most. The lifespan of the Greenland sharks is astonishing. They are estimated to live the average lifespan of 400 years, which is the longest of all vertebrate animals. An individual of this species attains sexual maturity when it reaches a body length of 4 meters. Nevertheless, it takes more than 150 years for this to happen, because the growth of the Greenland shark is extremely time-costly: 1 centimeter increase in the body length per year!

When I first got to know this species, I was stunned. As human beings, our lifespan is already longer than that of most other animals on Earth, but now, there is truly a species that readily lives 4 times of our lifespan. Imagine a Greenland shark which is now 350 years old. It has already witnessed most of the human’s modern history. When it was born, most people on Earth still believed in Aristotle and geocentricism, and the modern astronomy had not been established yet. This fact reformed the concept of life in my mind, to compel me to reconsider its limitation and potential.

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Our Neighbor the Space Octopus

Posted on May 4, 2021 by brandonlipper
“Fish-like” rover

While the potential of finding microorganisms on Mars has intrigued us here on Earth for a while now, more advanced life may live on Jupiter’s fourth largest moon: Europa. In fact, Professor Monica Grady has proposed that, not only is life on Europa likely, but said life may include organisms with intelligence similar to that of an octopus. Why can life exist on a moon outside of the solar system’s habitable zone? It likely meets three key requirements: liquid water, building blocks of life, and energy. Firstly, it is expected that a salty ocean exists below Europa’s icy surface based on the moon’s magnetic field and smooth surface that indicates warmer ice has risen to cover up craters. Next, radiation from Jupiter could turn Europa’s surface and water ice into O2, H2O2, CO2, SO2. In addition, carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur could have been around when Europa formed and asteroids/comets could have added to this. These materials are the building blocks of life. Finally, Europa needs an energy source and this is provided by tidal heating from Jupiter and radiation from Jupiter (the icy surface protects life below from the radiation).

A really cool aspect of this prospect, as shown in the image above, is the potential method for searching for life on Europa. While microorganisms could be brought to the surface by vents, we would also like to explore below the surface. That is why, in 2015, NASA gave a grant to a project developing a “soft robot” that swims like a lamprey. Hopefully we send a mission to Europa to look for life soon and maybe even find large lifeforms.

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Lucy Spacecraft

Posted on May 4, 2021 by ben141414

Source: Wikipedia

I chose to research Lucy, a future NASA mission, for my final blog. Throughout the semester, my favorite topics we have covered in class have been ones revolving around space exploration. I am fascinated by the complex missions that humans send out into space. Lucy is an upcoming mission set to launch from Cape Canaveral on October 16, 2021 that will explore asteroids in the solar system. It will visit one asteroid in the main asteroid belt and six Trojan asteroids. Trojan asteroids are asteroids that share an orbit with a planet and orbit either in front or behind the planet; these six share an orbit with Jupiter. The Lucy spacecraft will utilize gravity assists from Earth in order to maneuver through the solar system. Overall, it was interesting to learn about these mission plans, and hopefully the Lucy mission will provide valuable information about notable asteroids in the solar system!

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Dear Aliens – a retrospect

Posted on May 4, 2021 by Peter Taylor

Well, that’s a wrap. With the inevitability of Earth’s annual progression around the writhing sphere of fire and fusion that sustains our life, another semester comes to a close and another class comes to an end.

However, just as all things must end, all things must begin. Days, summers, worlds, perspectives, you name it. So as I look back on a semester filled with physical and intellectual and new horizons (see what I did there), I can recognize the humble beginnings of a new personal belief:

Male narwhals caress one another with their tusks in Nunavut, Canada.
narwhals – probably an Earth exclusive

Aliens definitely exist.

For the longest time, I didn’t believe in aliens. Maybe it was to avoid some weird fear of getting randomly abducted before taking an exam and being thrown around our solar system and forced to identify what world they put me on. Maybe it was because MARVEL made it seem too cool to be true. Or maybe it was because I saw a picture of a narwhal and thought, “yeah, there’s no way that thing exists anywhere else.”

APOD: 2008 January 4 - The Milky Way at 5000 Meters
the Milky Way – home to 37 intelligent civilizations?

Regardless, though, my thoughts have changed, largely in thanks to our work on extremophiles and the Drake Equation. For example, after using the Drake Equation, I calculated that there are probably over 4,000 civilizations in our galaxy alone. More importantly, though, last year two scientists at the University of Nottingham, who presumably have a much better idea of what they are doing than I do, used the Drake Equation and calculated that there are about 36 alien civilizations in our galaxy capable of communicating with us. Then, extrapolating the data by taking our Milky Way as one of 125 billion galaxies in the observable universe, I like the odds.

So, aliens, if you ever read this, I wrote you a little letter. I hope you like it.

Dear Aliens,

How’s it going? I hope you know I believe in you, and I hope if you’re out there that you believe in me, too.

Cheers,

peter

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solar system superlatives: Earth

Posted on May 4, 2021 by Peter Taylor

Welcome to the last episode of solar system superlatives. I know it’s hard to believe, but, alas, all good things must end.

In an effort to dry the tears brimming in all our eyes, I wanted to end this blog series on a happy note and on a celebration of vitality – by looking at the ethereal cascade of energy and beauty we call our home. The dazzling marble metamorphizing wind and water and light into the transcendence of life, itself.

sunrise from the ISS

Welcome, one and all, to Earth.

The Earth is teeming with life of all kinds, and it is the only known planet in the universe to contain any of it. With everything from humans ourselves to birds and giraffes to daffodils and sequoias to mushrooms and amoebae, life forms of all shapes and sizes call Earth home. Scientists also believe many other species may still be hiding, waiting to be discovered. However, among the discovered life forms, some of the smallest and seemingly innocuous boast the most incredible feats of survivability ever seen.

methane ice worm picture
methane ice worm

These remarkable little life forms are called extremophiles. One example of an extremophile is the bacteria Helicobacter pylori. Helicobacter pylori are an example of an acidophile, or an organism that thrives in highly acidic environments. These bacteria, given their affinity for highly acidic environments, live in human stomachs. Another example of extremophiles are the methane ice worms that live in the bottom of the Gulf of Mexico. These approximately two-inch long worms thrive in the methane mounds at the bottom of the ocean and probably feast on the bacteria there. If these creatures can live and love living in the most extreme conditions on Earth, then I would be surprised if we can’t find other life forms living in the extreme conditions found elsewhere in our solar system and galaxy!

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no planet orbiting me, but still feeling like a star

Posted on May 4, 2021 by wendyyb

i’m a tour guide for vandy, and a big point that i emphasize on all my stops is that, regardless of your abilities and background, you can find classes in all subjects that will interest you. and then i follow it up with a story, because no one really flies hundreds of miles to nashville to hear about what date cornelius vanderbilt was born. i regularly talk about how, despite not being a super ‘science-y’ person, i’m still able to take a science class that interests me and isn’t a super hard science like chem or bio. nonetheless: hard is a relative term, and, some days, astronomy was hard:

This is just a picture i took but here’s my blog lol: my blog (:

Like, really hard.

nonetheless, i’m happy i got the opportunity to try things outside of my comfort zone (isn’t that what college is all about?) and learn new things about something that i knew very little about (on the first day when asked “what do you want to learn about our solar system?” i said “black holes”). and while i may not remember the minutiae of asteroid impacts or kepler’s laws, there are certainly things that i will hold on to: when i go out with friends at night i always notify them of the moon phase and the rising & setting times. i’ve spent many conversations marveling at how we’re basically time traveling when we look at things that are far away. and the fact that people just figured that stuff out without the use of fancy telescopes or the scientific knowledge we have today: wild.

what really fascinates me, is that there’s so much left to know: between dark matter, and black holes, and aliens, there is so much left to explore. after watching this Ted Talk about the potential for other universes, i realize that we are actually in a really unique period of time. that the things we are seeing in space now will not look the same in a few hundred or thousand years because of the rate at which light travels. it feels almost scary, like we have to figure things out now or risk losing them forever.

so, while i may not be the next carl sagan, i might one day be teaching the next carl sagan in my classroom. and while i don’t have the information that will prime them to build a spaceship to the next galaxy, i have enough to make them excited about the possibility of finding what might be out there.

anywho: thanks for a fun semester (: HAGS ❤

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hoping for a good (tardi)grade on this blog

Posted on May 3, 2021 by wendyyb
Adorable Tardigrades Have a Surprising, Fatal Weakness | Live Science
Image of a Tardigrade, source: LiveScience

At first glance, tardigrades don’t look like much. Affectionately nicknamed “water bears” and “moss piglets”, it’s hard to believe that this millimeter long creature is one of Earth’s most durable extremophiles. According to BCC, tardigrades are found all over the planet from the bottom of the ocean, to Antarctica, to the tops of the Himalayas. They’ve been around for awhile too, fossils of tardigrades date back to over 500 million years ago. They are able withstand temperatures up to 151°C for 15 mins. and as cold as -272°C for 2 hours. Additionally they are able to survive extreme radiation and extreme pressure. If that wasn’t impressive enough, tardigrades are actually able to survive without water. Kind of. When lacking water, tardigrades enter what scientists call the “tun” state. Within the tun state, tardigrades retract their head and legs (much like a turtle), slow their metabolism to .01% of its regular rate and enter a coma-like state that resembles death, essentially allowing itself to dry out. When it comes in contact with water again, it reanimates as if nothing ever happened. Tardigrades have been known to stay in this tun state for 8 years before returning to life and could potentially live even longer. This becomes really interesting when considering extraterrestrial life. Though our current science informs us that life necessitates water, tardigrades introduce the potential of life on “uninhabitable” worlds, just waiting to be reanimated. Do you think there’s life like this out there?

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ExploreTheUniverse

Posted on May 3, 2021 by kjackson1456

Astrobiology is the study of life in the universe. A true interdisciplinary study, astrobiology combines elements of many fields of science such as astronomy, biology, chemistry, and geology—just to name a few. Astrobiology seeks to answer some of life’s biggest questions such as: Do extraterrestrial beings exist? Comparatively speaking, astrobiology as an official discipline is a relatively new filed of science. Having said that, there has been a recent spark of interest for the field and many American institutions such as Washington University have added astrobiology to their list of degree programs. As technology continues to evolve the issue of space travel becomes more manageable and we are able to explore more of space for those vital signs of life. OSIRIS-REx Mission made this video explaining what astrobiology is. It is pretty cool and definitely worth the watch.

It seems rather odd to think that out of the millions upon millions of worlds (not including those that have yet to be discovered), there is no other form of life. Surely, it may look different from what we consider life on Earth, though that simply requires that we broaden our understanding of what life is.

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ExploreVenus

Posted on May 3, 2021 by kjackson1456

In astrology, ruling planets are the specifically designated planet for each of the zodiacs. Since there are 12 zodiac signs and only 7 planets, some share the same planet such as Libra and Taurus who are both ruled by the planet Venus. Each planet is said to have a distinct energy that affect us at different times in different ways as Earth makes its way around the sun. Venus for instance, is associated with love, sensuality, and a value for the beauty in life. That being said, Venus brings with it an appreciation for that which is aesthetically pleasing, romantic explorations, and a desire for luxury and pleasure. This is felt most in the Libra and Taurus sign since they are both ruled by Venus. Many individuals may feel these ways or engage in these behaviors while the sun is in Venus, though Libra and Taurus may experience these feelings/behaviors more frequently or they may find they are is a part of their personality or character.

Nasa model of Venus

In astronomy, Venus is positioned as the second closest planet to our sun in the solar system, and it has an extremely thick atmosphere. That said, it is extremely hot there. Venus is one of the system’s terrestrial planets and is just a little smaller than Earth. It is also our closest planetary neighbor. Its bright white appearance is due to reflection of sunlight from its cloudy atmosphere. On its actual surface, everything has an orange tint due to its thick atmosphere.

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All About Tardigrades!

Posted on May 3, 2021 by captivatingcomet

Tardigrades are a type of invertebrate and extremophile since they are able to thrive in extreme environments. Other names for tardigrades are water bears or moss piglets. They are typically 1 mm long or smaller. Tardigrades can live in numerous different environments such as damp moss, flowering plants, sand, fresh water, and the sea. In 1773, a German pastor, Johann August Ephraim Goeze, discovered them. He called them Tardigrada, meaning “slow stepper”. Tardigrades have long, pudgy bodies, squashed heads, and eight legs that each have a hand with four to eight claws. Tardigrades can survive in environments as cold as -328 ℉ (-200 ℃) and as hot as 300 ℉ (148.9 ℃). Additionally, they can thrive in surroundings that have radiation, boiling liquids, large amounts of pressure, and are extremely dry. Surprisingly, tardigrades can survive in the vacuum of space, too. In the majority of these extreme conditions, tardigrades undergo cryptobiosis where their body dries and curls up into an almost lifeless ball called a tun. Here, their metabolism can be as small as 0.01% of its normal rate. They can survive in this state for several years or decades and can be revived in a few hours after being exposed to water. Tardigrades nourish themselves by feasting on fluids such as the juices from algae, lichen, and moss. However, there are types of tardigrades that are carnivores or cannibals.

In 2007, the Foton-M3 spacecraft was launched into space containing several thousand tardigrades; they stayed in space for 12 days. Once the satellite was back on Earth, it was discovered that most of the tardigrades had survived. Furthermore, a few female tardigrades laid eggs while in space, and the offspring were determined to be healthy. The fact that tardigrades were able to produce offspring in space gives some hope that tardigrades and similar organisms can be found on other worlds besides Earth.

A scanning electron micrograph of a tardigrade (taken from Britannica)

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