Could Dinosaurs Have Been Warm-Blooded?

For a long time, scientists have debated whether dinosaurs were warm-blooded or cold-blooded. Turns out, they were probably somewhere in between.

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Stacked Ball Drop and Momentum

What happens when you drop a perfectly balanced stack of balls? And how is the result like a supernova? The classic momentum transfer demonstration, at the next level.

A big thank you to my nephews and niece Drew, Max and Whitney for creating the trampoline footage!
Thank you to the Vlogbrothers for sponsoring this video, to Kyle Kitzmiller for filming, and to Island School for providing the balls (
Music: YouTube
Space Images/animation: NASA

Rayleigh Scattering: Why does the sky look blue?

raleigh scattering

««« By Stan Taylor…..

When light from the sun hits the Earth’s atmosphere, the shorter wavelength blue light gets scattered in all directions at the same time. This is why the sky appears to be blue. The intensity of blueness is greater directly overhead compared with the blueness closer to the sunlight. This is caused by the so-called Rayleigh effect.  Click on the link below for a grade 7 activity that illustrates the Rayleigh effect.

rayleigh_scatter activity

The Future of Spacesuits

The current NASA spacesuits use gas to maintain atmospheric pressure inside the suit. While necessary for the astronauts to survive, it makes the suits very difficult to work in. MIT astronautics engineer Dava Newman has developed a solution: A flexible, protective suit that applies the pressure needed directly to the astronaut’s body. Her suit will give astronauts new flexibility and range of motion as we look forward towards the exploration of other planets.

By: World Science Festival Staff

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What is a Calorie?

We hear about calories all the time: How many calories are in this cookie? How many are burned by doing 100 jumping jacks, or long-distance running, or fidgeting? But what is a calorie, really? And how many of them do we actually need? Emma Bryce explains how a few different factors should go into determining the recommended amount for each person.

Lesson by Emma Bryce, animation by Qa’ed Mai.

Please note that 1 Cal = 4.18 kJ

Sewer Lice

carbonate from 123rf

This activity is courtesy of Flinn Scientific Canada.




Use this popular, simple exercise to introduce some levity into the classroom and as an opportunity to demonstrate the importance of careful observations.


  • Observation
  • What is life?


  • Raisins, 10 to 20
  • Beaker or similar transparent container, 1000-mL
  • Carbonated beverage that could pass for “sewer-water” (i.e., 50/50,® Squirt,® or Mountain Dew®), 500 mL

Safety Precautions

There are no real hazards involved with this exercise as long as scrupulously clean beakers or non-lab containers are used. Laboratory glassware that may have previously contained any chemicals or solutions should be avoided. Normally food should not be eaten in the laboratory—this may be one exception for dramatic effect. Remind students to never eat in the lab—this is a “special” demonstration.

Click here for a printer-ready version of the complete activity including procedure and discussion tips.