With the current rise of privatized space travel, one industry that may very well likely be popularized within our lifetimes is asteroid mining. However the initial investment cost of getting to a profitable asteroid will be enormous, the payoff of mining and bringing back the metals that these asteroids contain would be more than worth it. We are currently aware of 5 different asteroids that are worth multiple quintillion dollars at the current market rate of the metals that are contained.
However, to play devils advocate, the pure profit from these asteroids would likely be much lower if they were actually brought back to Earth, thanks to the laws of supply and demand. The price for the metals contained in these asteroids would plummet do to the massively increased supply.
Still, that does not mean it would not be fiscally worth it to go after these asteroids. It may be probable that industry would increase with the lowered price of these metals, allowing humanity to advance without resource limitation.
As of now scientists believe there are three requirements for a planet to develop and sustain life. Liquid water, the appropriate chemical elements, and an energy source. Europa has more than enough water, as it is believed that below the roughly 15 miles of solid ice, lies twice as much water as in Earth’s ocean, even though Europa is a fraction of Earth’s size.
As of now the most likely way to get more information about possible life at Europa is to sample water from water vapor fumes shooting through the ice. We would have to send a spacecraft to Europa with capabilities of finding and sampling these fumes.
Europa is currently the best chance of finding life outside of Earth, and it is important to explore this possibility as it would significantly alter how we view the development of life in the universe. If life has developed on two separate bodies in the solar system, life may no longer be viewed as a freak of nature, but as a result of the right combination and not wholly uncommon features in nature.
A diagram of the Chicxulub impact and how ejecta could have reached the Upper Midwest, where the impactor samples were found.
In class, we discussed the Chicxulub impact, which is highly likely to have triggered the extinction event that killed the dinosaurs. Despite the large size of the impactor, the catastrophic impact and 65 million years of geological processes have hidden the exact nature of the impactor from scientists. While iridium deposits in sedimentary rock layers point towards a more metallic asteroid, there isn’t direct evidence of the composition of the impactor and if it was an asteroid or a comet. Recently, paleontologists discovered what they believe to be shards of the Chicxulub impactor preserved in amber from the moments after the impact. Some fragments in the sample are characteristic of Earth’s crust, but others contain more iron, chromium, and nickel. These elements are signs that these may be tiny pieces of the impactor, and point towards an asteroid as the culprit. While these results have not been thoroughly reviewed yet, this would bring us a step closer to understanding both the Chicxulub impact itself as well as the types of impacts and impactors we see on Earth.
Researchers were able to accurately map oceans, land, and vegetation from a pixelated image of Earth. This technology could be applied to exoplanets in the near future.
The search for extrasolar planets and alien life is a fascinating research focus that sits at the intersection of astronomy, physics, planetary science, and biology. As we have discussed in class, discovering exoplanets is a very difficult task, but we have discovered roughly 5,000 exoplanets to date and are making significant progress in that area. We currently analyze these planets at a surface level and try to make conclusions about their habitability based on their size, mass, the star they orbit, and the distance of that orbit. A potential next step would be to gather visual data about these planets, and a recent study suggests that we could detect the existence of surface features such as land and oceans with only a few pixels of information. Using new machine learning techniques, the researchers were able to correctly map out land and oceans on a blurry image of Earth. Future telescopes, like the next round of planned ground-based telescopes, could be able to produce images of exoplanets, so analysis technology like this could be used soon.
As I mentioned in class, it seems to me that our rate of discovery of potentially habitable worlds in and outside of our solar system is accelerating significantly. I think it is more likely than not that we discover evidence of alien life within my lifetime— do you agree or disagree?
These four terms are often misunderstood and the objects/occurrences they represent are thought of to be similar when in reality that is not the case. I am here to put these false assumptions about these misunderstood terms to rest.
Looking at the definitions. An asteroid is a rock in space orbiting the sun, a meteoroid is similar to an asteroid where it is also a space rock, but it is smaller in size. A Meteor is a flash of light across the sky, it does not represent the rock itself while a meteorite is a meteor which travels through earth’s atmosphere and hits the ground. The differences between these terms are often classified according to their size, position and relativity to earth.
With the inclusion of a comet as well, one can use this blog post to correctly identify an outer world occurrence and maybe use this knowledge to impress your crush
The Chichxulub Asteroid, the impactor which likely killed the dinosaurs. Source: National Geographic
Both nuclear weapons and asteroids are incredibly powerful and potentially dangerous objects with capabilities for mass destruction. The impact of the Chicxulub Asteriod about 65 million years ago had an explosive force about two million times greater than the Tsar Bomba, the most powerful man-made nuclear weapon ever deployed, which had an explosive power of 50 megatons of TNT. Doing some simple calculations, we can determine that the Chicxulub asteroid had an explosive force of about a hundred million megatons of TNT (50 x 2,000,000 = 100,000,000). For perspective, attached below is the explosion of the Tsar Bomba, which created a mushroom cloud 37 miles tall and could be seen from over 600 miles away (Britannica).
Fortunately, there is a potentially productive and responsible relationship between these two destructive forces. Using basic statistics and probability based off historical data, we know that it is significantly likely that within the next 10,000 years there will be a moderately size asteroid set to collide with Earth. This asteroid will be much, much smaller than the Chichxulub impactor, which spanned several km across. However, even a considerably smaller asteroid, with a radius of several dozen meters, still has enough destructive potential to seriously damage or destroy a small city. Thankfully, NASA is currently monitoring the 2,122 potential hazardous objects (PHOs) in our solar system, which are asteroids with radii over 140 meters that could someday impact Earth (source).
Due to their energy-dense properties, nuclear weapons are actually particularly effective at potentially deflecting an incoming asteroid. NASA claims that nuclear options are 10 to 100 times more effective at diverting incoming asteroids than non-nuclear options.
I think that considering the potential positive benefits of nuclear power is something equally as important as treating them with due respect and carefulness for their destructive potential. Ultimately, we may someday have to use a nuclear weapon to deflect an incoming asteroid, as long as we don’t destroy ourselves beforehand.
When the spacecraft New Horizons first flew past Pluto in 2015, astronomers didn’t really have too much of an idea of what to expect.
Pluto had only been discovered about 85 years earlier (source) on February 18th, 1930 by Clyde Tombaugh at the Lowell Observatory in Flagstaff, Arizona. Due to Pluto’s immense distance, small size, and laughable luminosity, the small planet was not only extremely hard to detect but also to properly photograph. The image below is taken by the Hubble Telescope, the most powerful telescope that we humans have access to. The Hubble Telescope is powerful enough to literally look billions of years into the past, producing images like the Hubble Ultra Deep Field, but the best image it could create of Pluto is the blurry mess below.
What the New Horizon mission revealed seven years ago continues to have implications today. Besides discovering that the planet actually has an incredibly interesting geographical domain, consisting of icy mountains, newly formed glaciers, an extensive hazy atmosphere, and an oceanic core, the exploration also revealed that Pluto is not alone. Pluto is in fact just one of several dozen, potentially several hundred similar dwarf planets in our solar system, which are similarly unexplored. This begs the question: is it time to send more spacecraft to the outer limits of our solar system? We obviously do not know as much as we thought we did about this systems.
Growing up with Pluto being known as the ninth planet, I’m interested in Pluto, its uniqueness and why it was revoked of the prestigious planetary title.
The discovery of other planetary objects in the outer solar system today known as dwarf planets made the switch of Pluto’s classification from a planet to a dwarf planet. These dwarf planets were about the same size of Pluto and has certain criteria to uphold. Dwarf planets has to orbit the sun, it has to have enough mass so gravity could pull its shape into a spherical object and it has to have cleared its orbit from smaller objects. Eris is the largest dwarf planet with Pluto coming in at a close second.
After the New Horizons’ mission, several characteristics of Pluto were discovered which made Pluto one of the most interesting planetary objects in the solar system. Pluto’s small size and distance from the sun made scientists believe that Pluto’s core will be heatless and Pluto would be geologically dead. They could not be more wrong. Pluto does not have a lot of craters hinting toward its young surface and/or geological activity. Pluto has a thin atmosphere with low atmospheric pressure. Pluto’s distance from the sun explains why it is mostly covered in ice. Pluto has ice volcanos, ice mountains, frozen lakes and actually has an atmosphere as the New Horizons mission picked up signs of dust devils, tornados and haze clouds on Pluto’s surface. For me, however the most interesting thing about Pluto is its frozen ocean and what lies beneath all that ice. Maybe there is a whole new world up for discovery?!
Discoveries of extrasolar planets and the growing pool of knowledge surrounding them has raised innumerable new questions. Many of these worlds do not follow the patterns or rules of planetary composition, location, etc. that exist within our own solar system. One of the biggest ones in response to these inconsistencies—is our current solar nebula formation theory correct? Do we need to tweak certain currently accepted theories and add others? Is the basic premise correct, or do we need to entirely reconsider what we know?
The consensus is that the latter of these questions can be ruled out—the solar nebular theory seems to hold true as an explanation. However, there are certainly absences in the theory that do not account for the realities we are seeing with extrasolar planetary systems. One of the largest inconsistencies is the close orbit of massive gas planets to their star; these ‘Hot Jupiters’ orbit at distances closer than Mercury to the Sun. Now fairly prominent and accepted as an idea, the theory of planetary migration accounts for this anomaly.
Planetary migration theory posits that these high-mass planets exert more gravitational pull on gas in the nebular disk as they grow bigger. The spinning motion of the disk creates a region of motion called a ‘spiral wake,’ which is characterized by its increased gas density. The inner part of this wake (closer to the star) travels faster than the outer portion, in accordance with Kepler’s third law. This exerts a gravitational pull on the planet as it trails ever so slightly behind its star. The outer portion has the opposite effect, draining the planet’s orbital energy and pushing it inwards. The general tendency of the planet then favors migrating inward rather than outward, even though the positive and negative forces exerted on it are practically equal. It is hypothesized that an imbalance in angular momentum between these two forces (of the spiral wake) are enough to initiate the planet’s migration inward.Researchers are uncertain why this is the case, but have confirmed that it is a habitual function of planet-forming gaseous disks.
Gregory P. Laughlin/Stephanie Freese
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486958 Arrokoth claimed its rank as a notable solar body after the New Horizons flyby in early 2019, a mission executed in conjunction with the Johns Hopkins Applied Physics Laboratory, and Southwest Research Institute. This object, often tagged with its informal name of Ultima Thule, is Trans-Neptunian Object (TNO) located on the outskirts of the Kuiper Belt. To date, it is the furthest object that we have been able to visit in our solar system. Unlike stars’ typically volatile interactions with each other, Ultima Thule is a contact binary, in which two stars merge to share their gaseous envelopes. This process creates the hourglass shape characteristic of the binary system (this shape even earned 486958 Arrokoth the nickname of ‘The Snowman’).
Measuring at an approximated 36 × 20 × 10 km, Ultima Thule is an incredibly small body to have been found at its whopping four-billion-mile distance from Earth. Its discovery is a testament to advancements in technology that make these missions possible; and, of course, the teams of people that are at the very center of these programs to begin with. In a press release from the day of the successful Ultima Thule flyby, NASA administrator Jim Bridenstine remarked, “In addition to being the first to explore Pluto, today New Horizons flew by the most distant object ever visited by a spacecraft and became the first to directly explore an object that holds remnants from the birth of our solar system… This is what leadership in space exploration is all about.”
