Category Archives: Science

The End of Cassini: Crashing Into Saturn

On September 15, the Cassini spacecraft will come to an end. It’s going to crash into Saturn after orbiting it for more than 13 years. That’s a long time.

Cassini has brought us an incredible amount of information. Some of it has been extremely exciting. Lakes on Titan, liquid water ocean on Enceladus, the spongy-looking surface of Hyperion, and the split personality of Iapetus. And then there are the rings and the atmosphere of Saturn. I talk all about that and why Cassini is crashing into Saturn in my most recent science video.

What are some of your best memories of the Cassini mission? Let me know in the comments section below.

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Did You See the Eclipse? I Did!

This is the second solar eclipse I’ve seen in six years. The last one was in Japan, and it was a total eclipse. This time, we had a partial eclipse here in Edmonton. I made a solar eclipse viewer with a cereal box, and it performed wonderfully. Curious to see the results? Well, check it out!

The things that I observed with the viewer that I found interesting were:

  • I could see clouds when they passed over the sun.
  • While the image was sharp, the camera found it to be difficult to focus on it, mainly because of the contrast between the dark box and bright light of the eclipse.

Outside the box, when it was at maximum eclipse, I noticed the following:

  • It got darker. It was still sunny, but it was a very odd sunny. It was like we had a 70% less bright sun. Things that I normally would have squinted at, like the white garage door, was no longer very bright.
  • It became cooler. It was a significant drop in temperature, and I wanted to wear a jacket. It was a 25 C day. That’s warm. But with 70% of the sun covered, the heat was less, and it felt cool.

I would have loved to have experienced the total eclipse. When I was in Japan, it was cloudy. I didn’t notice much of a cooling and while it did become significantly darker, it was still cloudy, and it wasn’t as impressive. I could still see the eclipse through the clouds, though. And yes, I did look at it without protecting my eyes with glasses. I couldn’t see it with the glasses, actually! The clouds were just the right thickness to be able to see the eclipse. But don’t worry, I only glanced at it quickly. And then when there was a break in the clouds, I used the glasses and took pictures through them.

Did you see the eclipse? Let me know!

How to Make a Solar Eclipse Viewer

Most of you are from North America, and I’m sure you know about the solar eclipse next Monday, right? The path of totality will cross the United States, but all of North America will get to see it to varying degrees of partiality. For me, it’ll be around 75% partial.

Do you have your solar eclipse glasses? They’re hard to find now. If you don’t have some, don’t worry! You can still observe the eclipse! Actually, I made one today with my daughter. Here it is:

An easy to make solar eclipse viewer made with a cereal box.

That’s right, it’s a cereal box. Curious how to make it? It’s actually very easy. I made a video showing how I made it, so if you want to try this out, then definitely watch the video!

Are you going to make it? Any kind of cereal box will do. You can use pretty much any kind of box, actually. Just make sure no light is getting in except through the pinhole. Let me know if you’re going to make it!

D Is for DNA

This post is coming a day late. I hope that’s not a problem with the rules of the A to Z Challenge! You see, I have some foreign DNA in my body. The common cold. I was too tired to get the video and post up last night. But here it is now! For the letter D, I’m talking about DNA. How many of these facts did you know?

And here are the facts:

  1. DNA stands for deoxyribonucleic acid.
  2. A DNA molecule is made up of two bipolymer strands wrapped around each other to form a double helix.
  3. There are four nucleobases represented by the letters C, G, A, and T. They are cytosine, guanine, adenine, and thymine.
  4. Nucleobases pair up, A with T and C with G to connect the two DNA strands to form the double helix.
  5. Only 2% of human DNA codes protein sequences. The remaining 98% have other various functions, which would require another full video to talk about.
  6. The species with the largest number of chromosomes is the ciliated protozoa with 29,640,000.
  7. The species with the fewest number of chromosomes is the jack jumper ant with only 2. But that’s for the females. Males are haploid and have only 1, the smallest number possible.
  8. Humans have 46 chromosomes, but other great apes, including chimpanzees, gorillas, and orangutans, have 48.
  9. More than 8% of the human genome is made up of retrovirus sequences.
  10. There is a 4% difference in the genomes of humans and our closest relatives, chimpanzees and bonobos.

Let me know in the comments section below what you knew.

E Is for Europa

Even though the A to Z Challenge is over, and I took a huge break, I’m going to finish it. A lot has happened over the last couple months, but it’s back! Today is the letter E, and I’m talking about Jupiter’s moon Europa! Did you learn anything new?

  1. Europa is the fourth largest natural satellite of Jupiter.
  2. It was discovered in 1610 by Galileo Galilei, along with the other three Galilean satellites.
  3. The surface of Europa is the smoothest surface of any world in the Solar System, consisting of water ice.
  4. Europa orbits Jupiter in just 3.55 days, with one side always facing Jupiter, as it’s tidally locked.
  5. Beneath the ice crust is an estimated 100 km deep ocean of salt water. But it isn’t clear if the ice is thick or thin. However, the amount of water on Europa is about two to three times the volume of Earth’s oceans.
  6. Europa has a weak magnetic field, best explained by Europa’s salt water ocean.
  7. Tidal heating from the interactions of Europa with Jupiter and the other Galilean satellites warms the interior of the moon, possibly resulting in hydrothermal vents at the floor of the ocean. This has led scientists to suggest that life may exist in Europa’s ocean.
  8. Europa most likely has an iron core and a rocky mantle.
  9. Observations by the Hubble Space Telescope provide further evidence of subsurface oceans, as plumes of water have been seen erupting to 200 km above the surface.
  10. Europa has an oxygen atmosphere. But it’s very thin, providing a surface pressure of only 0.1 micropascals.

Let me know what you learned in the comments section below!

C Is for Canada Goose

What other bird says “Canada” to you? Maybe the loon? Well, how about the Canada goose? For the letter C, I am talking about the Canada goose! Check out the video, which includes some bonus video of a v-formation I managed to catch.

And here are the facts. How many did you know?

  1. This large goose is native to the arctic and temperature regions of North America.
  2. It’s been introduced to other parts of the world, including the UK, New Zealand, Argentina, and Chile.
  3. They are extremely successful at adapting to human habitation, so they are a very common bird around cities and towns, now having a population of between 4 and 5 million.
  4. There are 7 subspecies of Canada goose.
  5. They range from 75 to 120 cm in length and have a wingspan of between 127 and 185 cm.
  6. In most bird species, sexual dimorphism is apparent in the differences between male and female bird appearance, but the male and female Canada goose are virtually identical, except for a small difference in weight. Females are smaller.
  7. They spend their summers throughout Canada and the northern United States, but breed in the southern US and northern Mexico.
  8. Canada geese eat mainly plants, but have been known to eat insects and fish. And sometimes they scavenge from garbage cans.
  9. They fly in a v-formation at around 1 km in altitude, but have been known to fly as high as 9 km.
  10. Canada geese are monogamous, mating for life. If one dies, then they can find another mate. They’re very faithful birds.

Let me know in the comments below which facts you didn’t know about or were the most surprised about.

B Is for Bees

The A to Z Challenge continues with the letter B! This time, I talk about bees. It’s springtime, so insects are now coming out. Bees are a very important part of our environment, since they pollinate flowers, and help us grow our plant crops. So, let’s take a look at the video.

Here are the facts, which I mentioned in the video.

  1. There are around 20,000 known species of bee.
  2. The smallest bees are stingless bees that are only 2 mm in length.
  3. The largest bees are the Wallace’s giant bee, a kind of leafcutter bee that grows to 39 mm in length.
  4. Although collection of honey by humans dates back 15,000 years, beekeeping didn’t begin until 4,500 years ago in ancient Egypt.
  5. A bee’s mouthparts are adapted to both chew and suck, having both mandibles and a proboscis.
  6. The explosion of flowering plants 120 million years ago did not coincide with the appearance of bees, which have been around for 100 million years ago, evolving from a type of wasp.
  7. A third of our food supply depends on pollinators, most of which are bees.
  8. Honey isn’t the only thing humans eat. In some countries, the larvae are also eaten.
  9. The decline in bees has been a major worry in recent years, and has been linked to various problems such as pesticides, loss of habitat, and climate change.
  10. It was once said that a bumblebee’s flight was impossible. We now know that the short wing strokes, rotation of the wings, and rapid wing-beats result in sufficient lift. They’re not impossible fliers anymore.

Coming up tomorrow is the letter C. It’s going to be another biological topic. Check back tomorrow!