Science Education Pedagogy Seminar

One of the greatest difficulties interstellar, or even just interplanetary, travel faces today is the problem of fuel storage. In order to accelerate to fast enough speeds to travel between planets in a reasonable amount of time, as well as to later decelerate, ships would need to hold a tremendous amount of fuel, which would then cause it to need even more fuel because of the higher mass.

The EmDrive will potentially solve this problem. Introduced in 2001 by a researcher named Roger Shawyer, the device seems to be able to create thrust without any propellant. The EmDrive went largely ignored by scientists at first because of the impossible contradiction it would make with the laws of physics if proven true. However, several independent labs have since recreated the drive and reported the same results as Shawyer: that it does, in fact, create thrust.

At first, researchers blamed the creation of thrust on some kind of measuring mistake, but even after extensive testing, they have still been unable to disprove the existence of thrust. It remains to be seen what actually causes the thrust, but if the thrust is actually caused by some kind of physical phenomena, it would mean a revolution in both the study of physics and in space travel.

Wow. In these last few months, we have gone over the entire cosmic calendar. The last topic of the class, life elsewhere in the universe, covered stuff that hasn’t even happened on this calendar yet. In this class, I really believe I’ve learned a lot of material, rather than memorizing a lot. Studying for this upcoming final, I feel rather prepared and confident.

Something that amazes me is that we as humans have really not existed for that long, yet we’ve come such a long way. We know so much. I’m extremely excited to see what we will accomplish in the next minute, hour and day of the cosmic calendar. Another thing I find fascinating is that this calendar isn’t complete. As we learn more about the Universe, we are filling in gaps and dates in the cosmic calendar. We’re trying to get a very detailed itinerary of how we came to be.

Something that interests me is that this is a class covering the Solar System, the last few months of the cosmic calendar. And yet, we aren’t even 100% sure of everything that occurred during this time. Heck, even the last week is a blur. And not only is it a blur for our Solar System, it’s a blur for our galaxy and any other planetary system out there. Even when we know everything we possibly can about our galaxy and solar system, there is still going to be so much to learn about the other billion ones out there.

The Drake Equation is an equation that was developed to help us determine what life exists in our universe beyond planet Earth. In class, we have been doing much work with the Drake Equation, including filling it out ourselves using our own estimates. But…is the Drake Equation useful or even worth our time?

If you are not familiar with the Drake Equation, it is a formula that requires a significant number of estimations. And these estimations are not as simple as the amount of jelly beans in a jar. Instead, they are incredibly broad concepts that are virtually impossible to know accurately. For example, how many life supporting planets exist PER solar system? We don’t know of any life beyond our solar system so how can we begin guessing this percentage for millions of other systems?

So, with such difficult questions that no one truly has a strong estimate of, is the Drake Equation necessary? Sure, if we knew the figures better it could be effective in calculating how much life exists in our universe, but what’s the point? In my opinion, it is good that we have the equation so we can focus our research better. However, I don’t think it will be an equation that we actually use in my generation’s lifetime.

To be, or not to be? Is that really the question? According to the Fermi Paradox, it’s a perfectly valid one.

The Fermi Paradox, coined after Enrico Fermi, is a theory that addresses life elsewhere in the universe as a probable reality. The only issue is, however, that no other forms of life (that we know of) have visited or even communicated with us (again, that we know of).

The paradox also addresses the issue of space–that is, just how vast and, well, empty, it is. If life were out there, shouldn’t we already know about it by now? If the universe is so unbelievably large, there’s no way we could find other life if it existed … right?

Such questions bring us to an important aspect of the Fermi Paradox, known as the Great Filter. This theory is that, even if the right conditions are present for life to form, it’s only a matter of time before some greater force wipes out that life. How reassuring.

The Fermi Paradox isn’t always so depressing, however, and one aspect is actually quite exciting. The Drake Equation is a formal way to calculate the probability of life existing elsewhere in the universe, and many believe it actually proves that (though probabilities may be small and time may have been of the essence) life exist(ed) somewhere amongst the stars.

The Drake Equation

If there is life out there, then why haven’t we communicated with it yet? Well, we’ve tried! In 1974, we tried to send radio waves into space to communicate a message, visualized below:

If the Fermi Paradox turns out to be a positive one (and the life-seeking optimists are happy), perhaps life elsewhere in the universe will get back with us soon. It may very well be the case, however, that other life forms may not be intelligent enough to communicate with us – or we may not be intelligent enough to communicate with them. There are endless possibilities to the Fermi Paradox, and the Drake Equation is only a venue for us to explore such possibilities. Maybe we missed communications with other life forms by millions of years. Maybe they’ve yet to come. Until then, the optimists and pessimists of the life-seeking niche will get to argue over probability (likely for a long time to come).

To be, or not to be? Is that really the question? According to the Fermi Paradox, it’s a perfectly valid one.

The Fermi Paradox, coined after Enrico Fermi, is a theory that addresses life elsewhere in the universe as a probable reality. The only issue is, however, that no other forms of life (that we know of) have visited or even communicated with us (again, that we know of).

The paradox also addresses the issue of space–that is, just how vast and, well, empty, it is. If life were out there, shouldn’t we already know about it by now? If the universe is so unbelievably large, there’s no way we could find other life if it existed … right?

Such questions bring us to an important aspect of the Fermi Paradox, known as the Great Filter. This theory is that, even if the right conditions are present for life to form, it’s only a matter of time before some greater force wipes out that life. How reassuring.

The Fermi Paradox isn’t always so depressing, however, and one aspect is actually quite exciting. The Drake Equation is a formal way to calculate the probability of life existing elsewhere in the universe, and many believe it actually proves that (though probabilities may be small and time may have been of the essence) life exist(ed) somewhere amongst the stars.

The Drake Equation

If there is life out there, then why haven’t we communicated with it yet? Well, we’ve tried! In 1974, we tried to send radio waves into space to communicate a message, visualized below:

If the Fermi Paradox turns out to be a positive one (and the life-seeking optimists are happy), perhaps life elsewhere in the universe will get back with us soon. It may very well be the case, however, that other life forms may not be intelligent enough to communicate with us – or we may not be intelligent enough to communicate with them. There are endless possibilities to the Fermi Paradox, and the Drake Equation is only a venue for us to explore such possibilities. Maybe we missed communications with other life forms by millions of years. Maybe they’ve yet to come. Until then, the optimists and pessimists of the life-seeking niche will get to argue over probability (likely for a long time to come).

The use of anti-matter propulsion might be the key to interstellar travel. Anti-matter is basically normal matter that has opposite charges. When matter and anti-matter collide with one another, they annihilate one another and energy is released. Unlike with nuclear fusion, where only 3% of the total mass of the matter is converted into energy, the collision between matter and anti-matter results in the entire mass of the matter and anti-matter being converted into energy. Thus, these reactions are highly efficient.

(Artist rendition of anti-matter propulsion rocket)

A rocket using anti-matter propulsion would work by using energy created from the reactions to superheat liquid hydrogen. This hydrogen would then be funneled through a nozzle and would expand in space, providing thrust. Scientists believe that a rocket powered by anti-matter propulsion would be able to achieve speeds of roughly one third of the speed of light. This would enable us to get to the nearest star system, Alpha Centauri, in roughly 12.5 years. Furthermore, another benefit of using anti-matter propulsion is that it is relatively safe. Unlike with nuclear reactors, anti-matter reactors would not produce any harmful radiation. In the event of an accident during lift-off, only a tiny amount of gamma rays would be released, which would not be harmful.

I was super excited when I saw the prompt for this blog assignment (not just because it was the last blog assignment)! Sometime last semester I was talking to one of my fellow physics major about Artificial Intelligence and at somehow we ended up talking about the Fermi Paradox (which I had recently read this cool article on).

Basically, Enrico Fermi (read the article though, guy was a physics boss) was like hey guys, something is rotten in the state of Denmark. In the galaxy, there are billions of stars like our Sun that are way older and they should have Earth like planets with intelligent life and even if they move at a snail’s pace, they should be able to cross the entire Milky Way in a million years. So why haven’t we seen them?

There are many offered solutions to this paradox, but one of my favorites is the Zoo Hypothesis, which says that other lifeforms exist and they know of us, but we haven’t reached some milestone they deem necessary before they contact us (for reasons of not wanting to throw our development off kilter). This is very similar to the Prime Directive on Star Trek. I also think it’s one of the lesser frightening alternatives. As it makes other civilizations seem benevolent.

Other possible solutions argue that other lifeforms know that it is unsafe to make contact for all sorts of different reasons. Who knows? Personally, as frustrating as it is, I kind of like the mystery and I’ll feel sorry for those who don’t experience it, as I think it adds to the sense of wonder of the universe. People in olden days would have been amazed by the concept of traveling cross country in a manner of days or even hours yet we don’t even think about any more today. The idea that the same could become of the universe itself is sad.

“But you don’t have to take my word for it.” Read some of the hyperlinked articles or watch these brief summaries!

The Chicxulub crater is a crater buried underneath the Yucatan Peninsula which is suspected to be the location of the impact of the meteor which wiped out the dinosaurs. The crater is more than 180km in diameter and 20km in depth. Estimates place the size of the impacting meteor to be at least 10km in diameter. Although there exists craters that are larger than the Chixculub crater, this particular crater is estimated to have impacted the Earth at a time similar to when the dinosaurs are thought to have roamed the world.

The crater was actually discovered by geophysicists Anotonio Camargo and Glen Penfield, who had originally been looking for petroleum in the late 1970s.  They had originally been unable to obtain evidence that it was an impact crater, but were later able to find gravitational anomalies and shocked quartz which hinted at it being one. The crater now stands as one of the largest pieces of evidence that the dinosaurs were wiped out by a meteor impact.

We talked much in class about different methods of discovering extrasolar planets, and Dr. G pointed out to us that the only reason people bother looking for extrasolar planets is to try and find life outside of our solar system.  To do this, scientists have to narrow down the list of extrasolar planets into a list of planets that resemble Earth. The first such planet discovered by the Kepler mission was Kepler-186f.

Scientists determine whether or not a planet is habitable by looking at its location relative to its sun. They do this by first learning how much total radiation a star emits. Then, through some complicated math, they check if the planet is located at a distance that receives anywhere from 25% to 88% of the Earth’s illumination. If these factors align, scientists can conclude that the planet lies in the solar system’s habitable zone, and thus deem it potentially habitable.

The Kepler Spacecraft is part of NASA’s Discovery Program (which is marked by having lower cost, but more focused missions). Kepler is the 10th stand alone mission of the program (the first was the Mars Pathfinder). Kepler’s purpose was to find exoplanets (with an emphasis on Earth-sized ones) and learn about their structures. Kepler was launched on March 7, 2009 and has lead to the discovery of  1,013 confirmed exoplanets and another 3,199 candidates. The most exiting ones being of course the “Earth-like” ones.

Earth-likeness is measured using the Earth Similarity Index (or ESI), the highest ESI discovered to date is 0.88 and that belongs to Kepler-438b (which is sadly 470 light years away in the constellation Lyra).

Kepler has had it’s share of problems though, originally it looked like it was “toast” back in 2013 when two of its reaction wheels stopped working (meaning it couldn’t stabilize/keep itself in one place)-however, engineers were able to use the pressure of sunlight to stabilize. However, crisis is not completely avoided, during the last scheduled contact (on April 7th) it was found that Kepler is in emergency mode (which despite being the lowest operational mode, also consumes the most fuel)-and has been since April 4th. Kepler is currently 75 million miles from Earth!

Further Reading:

• Wikipedia- Discovery Program
• Wikipedia- Earth Similarity Index
• Wikipedia- Kepler 438b
• Wikipedia- Kepler
• NASA- Kepler Homepage
• NASA-K2 Mission