Archives of Ask A Scientist!
About "Ask A Scientist!"
On September 17th, 1998 the Ithaca Journal ran its first "Ask A Scientist!" article in which Professor Neil Ashcroft , who was then the director of CCMR, answered the question "What is Jupiter made of?" Since then, we have received over 1,000 questions from students and adults from all over the world. Select questions are answered weekly and published in the Ithaca Journal and on our web site. "Ask A Scientist!" reaches more than 21,000 Central New York residents through the Ithaca Journal and countless others around the world throught the "Ask a Scientist!" web site.
Across disciplines and across the state, from Nobel Prize winning scientist David Lee to notable science education advocate Bill Nye, researchers and scientists have been called on to respond to these questions. For more than seven years, kids - and a few adults - have been submitting their queries to find out the answer to life's everyday questions.
Now, do cats' eyes glow in the dark? No they don't. Cats and dogs have some cells behind the retina that act like a mirror. These cells are found in a part of the eye called the tapetum. This mirror reflects light back, giving the rods and cones a second chance to pick up the small amount of light available at night. It is this tapetum that makes cats' and dogs' eyes seem to glow in the dark.
Humans don't have a tapetum. You may have noticed that if you use flash to take a photo, humans tend to look like they have red eyes. This is because there is a reflection of the red blood vessels behind our retinas. If you took a flash picture of your dog, you might see yellow or orange eyes instead. This is a reflection of the light of the flash by the dog's tapetum.
- How does burning gasoline make a car move?
- How small is the smallest thing you can see under a microscope?
- How are the colors in a rainbow made?
- Can you turn gas into a solid form?
- What exactly is radiation and why is it harmful? What can it do to you? How is it made?
- How does a particle accelerator work and why is it so useful?
- How many dimensions are there?
- How do lasers in machines work?
- What causes the electron within an atom to emit photon packets? We were told to make a diagram of it. What causes the electron to skip down a level and emit photons?
- If an object passes in front of a projector/point-source of light that illuminates a screen far away, it will cast a shadow on the screen. Now, if the object moves fast enough, and/or if the screen is far enough, the shadow will move much faster than the object, and at a certain speed of the object, the shadow will move faster than the speed of light. What would a bystander, or a camera, see?