NASA announcement: Arsenic-based life form discovered on Earth. NASA held a press conference Thursday afternoon in which they revealed the discovery of arsenic-based life forms on Earth.
As Marc Kaufman explained: All life on Earth - from microbes to elephants and us - is based on a single genetic model that requires the element phosphorus as one of its six essential components. But now researchers have uncovered a bacterium that has five of those essential elements but has, in effect, replaced phosphorus with its look-alike but toxic cousin arsenic. News of the discovery caused a scientific commotion, including calls to NASA from the White House and Congress asking whether a second line of earthly life has been found. Secrets of the Sun. Earth Science Lesson Plans. Astronomy Picture of the Day. Year of the Solar System: Topics: It's What Keeps Us Together: Classrooms. Gravity is a challenging topic, but can be built from prior knowledge throughout different grades.
Unlike many space science concepts, this topic lends itself to hands-on experiments in the classroom. Students have a variety of misconceptions about gravity that will need to be addressed at any age level; for more information about misconceptions about gravity, you may want to read "Learning about Gravity" in the Astronomy Education Review. Sandra Kaszynski. Solar System.