Presentations Day in November

For science this month, we've been learning about insects--especially ants. Liam and Delaney presented what they learned for the presentation group.

We created a chart to help us identify what are insects.....

To be an insect you must have three body parts--head, thorax, and abdomen. You must also have six legs and have an exoskeleton or hard shell instead of bones to keep you together. Some insects also have antenna and/or wings.

We learned that Liam is NOT an insect, along with dogs, horses, crabs, scorpions and spiders (they are arachnids) however, the other bugs on the chart are indeed insects. We also learned that insects are further divided into sub group--bugs, beetles and other such types (we didn't dwell on this very much).

It was a relief to know that although he's quite the stinker, he's not a stink bug! (not enough legs or body parts :)

For snack to share with the group, we made some 'ants on a log'. Yum!

Cailin and Delaney presented a puppet show about the Pilgrims and the Massasoit Indians and the first Thanksgiving. Cailin wrote the play.

Connor chose to tell us about black holes.

Black holes are enormous points of gravity. They are so powerful that the escape velocity is the speed of light. what is escape velocity? Supose that the Earth were to be crushed down to only two thousand miles across. It would have the same amount of matter in it, but the matter would be more compact. What would happen? Whenever a rocket got launched, it would take twice as much energy to get out of Earth's gravity. Note that rockets don't really have escape velocity, as escape velocity is the speed necessary at the planet's surface to escape, without constant propulsion or 'push' from the vehicle. If you were to launch something out of a catapult into space, it would have escape velocity. Suppose earth were crushed down to just thousand miles across. Our catapult would need twice as much energy as before, four times our original need. If we were to launch it from a black hole, how fast would the catapult need to launch shoot it's ammo? The pellet from the catapult would have to travel at at the speed of light!

Black holes are invisible. Why? Because light itself can't escape from them. When we see an object, we see the light coming off of the object. Black hols are invisible because no matter how much light goes into one, none comes back out. How do we know they exist then? Astronomers are able to detect black holes by their effect on the surrounding area. They watch the movement of stars being drawn in by the black hole's enormous gravity.

Most galaxies are formed by black holes. Black holes with the mass of millions to billions of times the mass of the sun pull stars and planets in and bring them into orbit, much like a star and planets in a solar system. also like a solar system, each star orbits the black hole.

With in each black hole, there are two main areas. These areas are known as the event horizon, and the singularity. The event horizon is known to many as the point of no return. That is because it really is' the point of no return' Once you've entered the event horizon, there's no going back. So how do we know about the singularity, which is located within the event horizon? Mainly mind boggling mathematical calculations. The singularity, which comes from the mass that the black hole was made from, is where everything the black hole "eats" goes to. It is believed to have infinite mass.