In a couple of days, a large meteor will pass between the Earth and the Moon’s orbit.  The Asteroid named  2005 YU₅₅ is 400 meters long and at its closest point will pass 325,000 kilometers from the Earth traveling 13 km/s (30,000 mph).

The Impact Earth website allows you to calculate the impact of various asteroids if they were to hit the Earth. In this case if the YU₅₅ did hit Earth we could expect the equivalent of 8.49 x 10¹⁸ Joules = 2.03 x 10³ Megatons TNT or a 6.8 size earthquake. If it hit the deep ocean, 45-meter Tsunami waves between 2.3 meters (7.6 feet) and 45.7 meters (150 feet) would be expected.  But you will be happy to know that the average interval between impacts of this size somewhere on Earth during the last 4 billion years is 1.1 x 10⁵years (and if you need a brush up on your scientific notation, just move the decimal point five space to the right so it is 110,000 years). And just to be precise about the vocabulary, when it is traveling in our solar system it is an asteroid, but when it crashes through our atmosphere and breaks up into pieces that hit the Earth, they become meteorites.

Impact Earth data for 400 m Asteroid

It is interesting to use Impact Earth to see the effects of various size asteroids on the Earth. Indeed, student exploration will allow them to realize some of the parameters that will affect the collision including speed, density of asteroid, and angle of impact. The Impact Earth calculator is a good start but it leaves me a bit flat. No matter what size Asteroid, the impact animation is always the same. The depicted size of the asteroid should resemble the number that was entered. But the data are useful, and students could ask and answer many questions about asteroid impact, producing deeper asteroid understanding and inquiry skills.

Famous Asteroids from Adaptive Curriculum Animation

Angie, one of my science methods students shared this article with me. ScienceDaily (2009-03-28) — Self-led, self-structured inquiry may be the best method to train scientists at the college level and beyond, but it’s not the ideal way for all high school students to prepare for college science. That’s according to findings of a new study. See: http://www.sciencedaily.com/releases/2009/03/090326114415.htm#

With a partner, my secondary science methods students selected a tree and then combined their ample knowledge, creativity, and critical thinking and came up with several methods to determine the height of the tree.

Linda Dee and Karen Schedler were helping my students learn about Project Learning Tree (PLT) and its many science activities. My students now have the assignment to develop a lesson plan using a PLT activity and then teach a high school or middle school class using this lesson plan.

This class of students has already earned my respect for their knowledge, abilities, and great attitudes, but it was still exciting to see them apply what they know with their creativity and critical thinking. Indeed the process was just as important as the result. Their tree-height-measurement methods included (a) having a partner of known height stand by the tree and estimating how many of them it would take to reach the top of the tree; (b) measuring the shadow length of the partner and the tree and using ratios; (c) holding a vertical ruler up, with the partner at the tree, and using the marking of the ruler to determine ratios for the heights, and (d) comparing the tree height to a building and then counting brick segments on the building to determine height. Of course, if a protractor was on hand we could have used the distance from the tree, angle to the top of the tree, and some trigonometry to make this estimate.

The tree height estimates were compared to a value found by using clinometers. These nifty devices, we were told, give a pretty accurate reading. You measure off 66 feet and look through the viewer with one eye and line up a horizontal line with the other eye. There were two scales for viewing the height of the tree, one in feet and the other in meters.  In many cases, my students’ estimates were pretty close to the clinometers’ readings.

I was glad to see my students using metric measurements because we had talked about this before our spring break. My advice is to have their future students do all their measurements using the metric system and NEVER convert back into the imperial system. But with the “66 feet” distance and foot scale on the clinometer, it seems like our forestry colleagues, at least in the US, are not fully metrified. Prior to this, I had thought that the only people of science who were not completely immersed in the metric system were US meteorologists. It is obvious that some science traditions don’t change easily.