Stay warm and curl up with some hot chocolate in new spacey AstroCamp gear! You can win by entering the “Winter is Coming” contest today!
Our Astro Goodie bag prize includes a hoodie, a beanie, a water bottle, and some tasty hot chocolate:)
You can earn entires by visiting the website or commenting on this blog post. Check it out and feel free to make multiple entries to increase your chances! Prizes can only be delivered to those within the United States.
Today at Guided Discoveries we are thankful for so many things. Thank you to Ross and Kristi Turner who started it all over 35 years ago. Please watch these videos to find out just a few of the things we are thankful for at AstroCamp and CIMI. Happy Thanksgiving everyone!!!
Did you know the nearest star to our sun is 24,942,474,700,000 miles away? The nearest galaxy is about 14,919,633,000,000,000,000 miles away? Those are enormous numbers that are difficult to even imagine or understand!
Proxima Centauri, Credit Hubble
This is why when scientists talk about the distance to nearest stars, they don’t use miles. Instead, they use a measurement known as a light year. Light is the fastest thing in the universe, traveling over 186,000 miles per second! Over the course of one year, it goes about 6 trillion (6,000,000,000,000!!!) miles. This is what we know as a light year.
Some things are still really far away even in light years, but it makes it much easier to compare and understand what things are astronomically close to or far away from us. With our new way of measuring, the nearest star is about 4 light years away. The Andromeda Galaxy is 2,560,000 light years away! That’s still a big number, but its easier to understand how much further away it is than the nearest star.
Andromeda Galaxy (Creative Commons/flickr)
Light years have another convenient and very cool meaning. Since the light from a star or galaxy has to get to the Earth for us to see us, it means that the light had to travel here! Looking at that light means that we are looking at the star the way it was 4 years ago. Looking out in space is actually looking back in time, which can teach us lots of things about our universe.
Looking at the Andromeda galaxy, we are looking at it the way it was over 2 million years ago! Using the Hubble telescope, we have been able to look out at galaxies that are over 13 billion light years away, allowing us to look back to very early in the universe.
Hubble Ultra Deep Field Credit NASA/ESA/Hubble
Watch this video that further illustrates the enormity of a light year!
When a Line Isn’t a Line or Who’s Line is it Anyway?
What is the shortest path between two points? I bet most of you said a line, and in a lot of circumstances you would be correct. The problem is that this is only true if you are using a flat space like a sheet of paper. When your space begins to curve, you need to become more creative. Let’s take the cities of New York and Tokyo as an example. The shortest distance between them would be a straight line going through the Earth, but that’s no help to planes that need to stay above the ground. So airlines need to figure out a more complex path to make the journey as efficient as possible. This path is called a great circle! For our New York to Tokyo flight you need to travel north almost past Alaska to travel on the great circle.
Here is a fun site that you can use to map great circles connecting airports around the world: The Great Circle Mapper
Now you might think that outer space would be an escape from these silly curved geometries, but you would be very wrong. Einstein’s theory of General Relativity showed us that space is very far from flat. Any object with mass will warp space much like a weight will warp a trampoline. The heavier the object, the greater the warping. This is the basic principle of gravity! One of the interesting effects of this curving of space is that light will behave like our airplane and always follow the shortest path between two points, which often isn’t a line. That is what our vortex table is meant to show. The marbles are trying to go from one side of the metal ball to the other. If the ground was flat, they could simply go right next to it, but in our curved fabric space, the shortest path is a nice even circle several inches from the metal ball.
In space, we have even more extreme cases. For example, the light from a star might be split going around an object like a black hole. Some of the light goes around to the left, some of the light goes around to the right. After navigating the black hole, the two beams of light might eventually converge when they get to the Earth. A telescope detecting these two beams would see two identical stars on either side of the black hole, one on the right one on the left. In reality, there is only one star behind the black hole, but the telescope doesn’t know any better. We call this gravitational lensing, just one of the mind-bending things that can happen in space. Here is a diagram to make things slightly less clear than mud. The gray stars are what you see, the black is what is real.
CAUTION: DO NOT TRY THIS AT HOME! LIQUID NITROGEN CAN CAUSE TERRIBLE BURNS! (Death of living tissue caused by the extreme cold.)
Liquid Nitrogen can be scary. We call it a cryogenic fluid because it can rapidly cool substances down to temperatures around -321 degrees Fahrenheit. Unprotected human body parts are not immune to the danger at all. The water in our body will cool down rapidly and cause them to freeze solid, to the point where they could potentially break. That’s where we got the idea to pull this little maneuver, but with a banana in the glove instead of a finger. Just be warned though, we are professionals that know the limits of liquid nitrogen and how far to keep it away from our bodies. Please do not try this at home!!
But in science fiction, cryogenic substance like liquid nitrogen have a long and storied history; mostly being used to put humans into a deep freeze from which they can awaken many years in the future. Cryostasis as it would be called, could be very convenient for a couple of reasons: it could preserve astronauts on interstellar voyages that would normally last longer than a human lifespan, or perhaps preserve a person dying of a terminal illness until the cure is discovered. This type of technology could be very useful if it ever proves feasible. Studies have shown that if the cooling is done slow enough living cells can be preserved using this method. So perhaps we’ll see the first cryogenic human in our lifetime. Sorry to disappoint the conspiracy theorists out there, but Walt Disney is not currently frozen in liquid nitrogen. That’s just a rumor.
In “The What to Freeze Series” we will experiment with freezing different objects. What do you want to freeze next?
We would like to thank you for visiting our blog. AstroCamp is a hands-on physical science program with an emphasis on astronomy and space exploration. Our classes and activities are designed to inspire students toward future success in their academic and personal pursuits. This blog is intended to provide you with up-to-date news and information about our camp programs, as well as current science and astronomical happenings. This blog has been created by our staff who have at least a Bachelors Degree in Physics or Astronomy, however it is not uncommon for them to have a Masters Degree or PhD. We encourage you to also follow us on Facebook, Instagram, Google+, Twitter, and Vine to see even more of our interesting science, space and astronomy information. Feel free to leave comments, questions, or share our blog with others. Please visit www.astrocampschool.org for additional information. Happy Reading!