What we see with our eyes is visible because light bounces of surfaces in the world around us and then interacts with the receptors in our eyes. In this sense we “see” light all the time. But, much in the same way we can stand next to a train track and watch a train speeding by, can we see a beam of light speeding past us? Until recently this was extremely difficult because light travels incredibly fast (186,282 miles per second). In the video below, the folks from Planet Slow Mo, Gavin and Dan, visited the Compressed Ultrafast Photography (CUP) Laboratory at the California Institute of Technology (Caltech) where researchers are able to film events at speeds up to 10 trillion frames per second. By exploiting the scattering of light as it moves through a medium, the researchers are able to film beams of light as they travel! Check the video below.
At the NASA Goddard Space Flight Center in Greenbelt, Maryland, they have an exhibit with a rock brought back from the moon by the astronauts of Apollo 14. The rock is made of material that solidified after the lunar surface was melted by a meteorite impact many millions of years ago
Most people stop for a few seconds at this exhibit and move on. I guess that in their minds a rock is not something very exciting. However, my reaction to this exhibit was: wow! Mankind first took to the air in powered flight on 1903 when the Wright Brothers flew their rudimentary glider at the beach at Kitty Hawk, North Carolina, and only 66 years later in 1969, the Apollo 11 spacecraft landed on the moon. This rock is a fragment of another world! It was brought back to our planet by our species across 240,000 miles of the dark, cold, void of space. This awe inspiring achievement is a testament to the power of science and technology and our determination and yearning to dream, explore, and discover. I look at this rock and not only merely marvel at what we have accomplished, but I also wonder what amazing discoveries and feats we will achieve in the future.
This post has nothing to do with breathing the same air as Kings, Queens, or other aristocrats. It is actually about breathing the so called Noble gases, Helium, Neon, Argon, Krypton, and Xenon. This crazy experiment performed in the video below by Cody from Cody’s Lab is not without risk (even though these gases are elements that are quite unreactive), so don’t try it at home! If you want to skip ahead to the time in the video where he starts breathing the gases, it occurs at minute 4:16.
As you saw in the video, his voice went from a seemingly very high pitch after breathing the lightest gas, Helium, to a seemingly very low pitch after breathing the heaviest gas, Xenon. This is because Helium is lighter than air and the sound waves produced by the vocal chords propagate faster through it. This has the effect of amplifying the high-pitch components of the voice. With Xenon, sound waves travel slower, and this has the opposite effect. However, what is really affected by the gases is not so much the pitch of the sound but its overall quality or timbre.
We seldom see starfish from below. This video features the underside of a starfish at the National Aquarium in Baltimore. The starfish has dozens of tiny feet called podia. Scientist thought that these podia contain suckers that allow the starfish to cling to glass and other surfaces by a suction process. However, there is also evidence that the podia secrete sticky chemical substances that help the starfish attach to surfaces. The starfish can extend and retract these podia using water pressure generated inside its body through what is called a water-vascular system.