Cosmos Computed

Planet original Last month, I drew a couple astronomy-related pictures using a graphite pencil on a sheet of white paper. The problem with pencil sketching is that it's hard to draw white glowing objects... so I sketched a negative, and then uploaded the images to my computer and inverted them. Then I increased the contrast to improve the black background and enhance the white. The image at the top of this post is a ringed planet, possibly Saturn. I included three moons and some lighting on the backside from the rings. The whole image was smaller than a dime. Black hole original The image below is an imagined view of a black hole. I included high-energy jets of ejected material and an accretion disk. Most black holes are not actively consuming material, and do not have jets. But those are boring to draw. New posts every month - subscribe for free !

Imagine the universe is filled with water. Instead of empty space, every inch of it contains pure water. No planets, no stars, only water. What happens? And what would happen if an air bubble formed? The answer to this question requires a basic understanding of gravity. Gravity is very important. It helps hold matter together, bends light, and distorts space-time (which, incidentally, is how it bends light). It also makes it possible to play football, and as Americans are big football fans, they would certainly agree that we couldn't live without it. Unfortunately, many Americans don't understand how gravity works. Admittedly, scientists haven't figured out a lot of things, but we do understand it well enough to make predictions and model physical events. One of the important things about gravity is that its strength is proportional to the inverse of the square of the distance. In other words, it gets weaker as you get farther away, based on the equation: F = c/d 2 where c

Keystone on opening day Keystone Ski Resort just opened for the ski season on Friday. I went up to the resort that same day. There was only one run open (not including the beginner area at the top of the mountain), but it was awesome nevertheless! One of the main downsides to skiing on opening day is the number of people. There must have been about 2500 people on the mountain at the same time as me (not including the people snacking in the lodge). To keep the lines moving, the lift attendants made sure that the lift was completely full, with 4 people per chair. Even so, the wait to get on the lift took a long time. At one point when I was standing in line, a thought came to mind: the line was constantly being filled with more and more people, but it never got longer because the chair lift was carrying the people away at the same rate. So what would happen if the lift attendants only put 3 people on each chair, instead of 4? This would disrupt the balance: the inflow of skiers would be

Over my fall break (which lasted 1 day), I wrote a JavaScript program that would render a sphere. I thought it would be a fun way to practice math and programming skills simultaneously. As usual, I used my FireTools.js library to help with graphics as well as some other functions. To render the sphere, I wanted to take every pixel on the screen, and calculate the color of the pixel. The color would vary depending on which part of the sphere the pixel was displaying. If the part of the sphere was facing the light source, it would need to be brighter than a part of the sphere facing away from the light source. To find the brightness of each point on the surface, I first calculated the XYZ coordinates of that part of the sphere. This is also equal to the normal vector at that point. I took the dot product between the light source's direction and the normal vector. This is a mathematical operation that tells me whether the surface is aligned with the light source, as well as the percen

Near the end of last month, the moon passed entirely through Earth's shadow, resulting in a full lunar eclipse. The moon didn't completely black out, due to sunlight scattering through Earth's atmosphere. Instead, the moon had a dim reddish-brown glow. Of course, I took I lot of photos of this celestial phenomenon. I started taking photos during totality. I kept taking photos a couple times per minute, for a period of about 1.25 hours, until the moon was fully lit. My goal was to put the photos together, for an animation of the moon passing through the shadow of the Earth. "Fake" crescent One thing I thought was pretty neat was when the partial lighting of the moon formed a perfect crescent. The crescent looked a lot like the waning crescent phase of the moon, but there was something strange about it. It reminded me of the artificial images of the moon that you'll see when you use a star-mapping program. The reason is this: for a real crescent moon, the lighti

I'm thinking of two common English words, W1 and W2. W1 is half as long as W2, but has twice the syllables. When combined, the two words form a phrase that can be used to refer to a nonspecific stage of a meal. The letters in these two words can be rearranged to form two new common words: W3, and W4. W3 is half as long as W4, and it also has half the syllables. The two words, when combined, may be used when telling somebody to draw with a certain art medium. What are all four words? New posts every month - subscribe for free !

The Perseid meteor shower is coming up! After midnight on Tuesday, and again on Wednesday, an observer under a dark sky may see up to 100 meteors per hour - an average of nearly 2 per minute. If you live in a city, the light pollution will wash out most of the meteors, so the countryside or mountains will be a much better place to watch them. Meteors start as small bits of material floating in space, usually dropped from comets that passed through the area. At this stage, they are called "meteoroids". When the earth passes through a cluster of these particles, they hit our atmosphere and burn up as meteors, and we have what's called a meteor shower. If you're looking up at the sky, and you see a streak of light zip a short distance and then disappear, this is a meteor. One of the best things about this particular shower is that the moon won't come out all night, so the sky will be darker than usual - making it possible to see more meteors than in most showers. If

212° F Let's play a little game. I'll list a bunch of possible actions. Each action will have 2 variations, (a) and (b). You choose either (a) or (b), depending on which would be safer (or less painful). Each of the questions will involve an oven hot enough to bake a cake (350° F), and a pot of boiling water (assume we're at sea level). So... would you rather: 1.     (a) Stick your hand in the oven     (b) Stick your hand in the boiling water   ... for a period of 10 seconds 2.     (a) Leave a fork in the oven     (b) Leave a fork in boiling water   ... for a period of 15 minutes. Then hold the fork tight with your bare hand. 3. Fill a jar to the top with cool tap water. Then:    (a) Place the jar in the oven    (b) Place the jar in the boiling water   ... for a specific, but unknown, period of time. Then remove the jar and put your hand in it. First see if you can figure these out yourself. They shouldn't be too hard. If you have trouble, heat up your oven and boil a p

This morning, New Horizons became the first spacecraft to make a flyby observation of the Pluto system. During the mission, the spacecraft captured the most detailed photographs of Pluto's surface we've ever had, and possibly ever will have. It also found many new properties including size, mass, atmosphere, and surface composition. In a period of a few hours, we discovered more about Pluto than we've found in the 85 years since Clyde Tombaugh captured its first photograph. Before After  (images credit: NASA) To complete this mission, the spacecraft flew for more than 9 years through the emptiness of space. This may sound like a long time, but it's actually amazingly quick. In fact, New Horizons set the record for the fastest speed at launch, and during the flyby, the spacecraft was moving at a rate of over 30,000 mph, or roughly 50 times the speed of sound. Picture an object twice as heavy as a grand piano moving 25 times faster than a bullet from a gun. Yikes. The man

I have some crazy news! I was radiated by some radiation, and became radioactive. Over time, my radioactiveness decreased, and as it decreased, my mass decreased as well. I am now a foot shorter than I used to be, and weigh 50 pounds less! At the top of this post, you can see a picture which proves it. In the photo, I'm sitting on a weird box that materialized in the middle of the road... Okay, so you probably know what's going on here. I didn't really shrink; I'm obviously sitting on a chalk drawing. I designed the chalk drawing to look 3-dimensional when viewed from a certain angle. From other angles, it looks totally different; some of the lines that appear parallel in the photo aren't actually parallel at all. It only looks that way because it's an illusion. Here's another example: This was a little more complicated to draw. Not only were there parallel lines, but there were also circular shapes and hidden areas. And here's my best chalk drawing so f

A few days ago I found a field full of bright yellow flowers. It looked kind of nice, so I started taking pictures. My main goal was to get a photo which showed the vast number of flowers, without any extra information that might distract the mind. I ended up with this: There are probably a couple thousand flowers in that photo. I was amazed at how many flowers there were. Anyway, as I was photographing the flowers (probably Perky Sue), I noticed that there were a lot of bees in the field, buzzing from flower to flower and (presumably) collecting nectar and pollen. So I took some photos of the bees. Of course, I didn't stop at that. Among other photos, I got a photo of a giant dandelion (actually called a Salsify, although "Goliath Puffweed" would suit it way better): A cactus flower: A flowering yucca ( not to be confused with yuca, also known as cassava, which is toxic when raw, and grows in South America): And daisy fleabane, which is a weird name for a cool flower: Y

You may have noticed that my blog background changed a couple days ago. I've been meaning to change it for quite a while, but I didn't get around to it. Then, a few days ago, I had some free time on my hands. Why not create a 3D model of Earth, I wondered? So I pulled up Blender (a free computer graphics program I use) and got to work. I actually wasn't entirely sure where to begin, but I had an idea of the basics. I needed to: Map some terrain onto a sphere Make an atmosphere Create clouds Prevent the clouds from looking like a weird shell around the planet I'm not fully fluent in all the different techniques and features for Blender, so I looked for a planet Earth tutorial online. I soon found a BlenderGuru tutorial describing how to create and render a model of the planet Earth. The problem with the tutorial is that it was for a different version of Blender, and as a result didn't do everything I wanted to do. I watched most of the tutorial, did some more Google

Imagine you have a blender. To your blender, you add a couple scoops of ice cream and some milk. Then you press the buttons on the blender. Soon, you have a delicious vanilla milkshake. Next, you add strawberries and press buttons again. The result is even better than before: a strawberry milkshake. Input Output Of course, strawberries aren't the only option. Suppose that, instead of strawberries, you added cocoa powder and avocado. The result is a chocolate-avocado milkshake. Or you could have added some mint leaves, for a mint milkshake. Or some peaches, for a peach milkshake. In each of these cases, you pick the ingredient, and get a different milkshake. Whatever ingredient you pick, the result is always a milkshake. In other words, the blender took your ingredients, and returned a flavor of milkshake. The blender is like a function. In math, a function takes a number, and follows a set of rules to do something to that number. No matter what the number is, the function always fo

Monosodium glutamate, commonly abbreviated MSG, is a very common chemical used to enhance flavors in food. MSG works by activating the "umami" receptors on the tongue, effectively enhancing flavors and making food taste a lot better. This is similar to the way sodium chloride (table salt) works, but MSG is much more powerful, so sodium content can be reduced by adding MSG to food. For this reason, many food companies use MSG as a food additive. Despite these apparent advantages, most people would agree that MSG is unhealthy and should be avoided. Sensitive individuals even experience negative side effects after consuming food containing MSG. But what exactly is wrong with MSG? If a person is not MSG sensitive, is it okay for them to consume it in their food? Virtual model of monosodium glutamate Before answering these questions, it would be best to start with the molecular structure of MSG. Monosodium glutamate, also known as sodium glutamate, is an ionic compound with the f