Using NewsHour Extra Feature Stories

Overview: NewsHour Extra features stories can help students identify and interpret key issues in current events. This activity anticipates one class period, but the follow-up essay might be assigned as homework, or in another period.

Warm Up: Use initiating questions to introduce the topic and find out how much your students know.

Main Activity: Have students read NewsHour Extra's feature story and answer the questions on the reading comprehension handout.

Discussion: Use discussion questions to encourage students to think about how the issues outlined in the story affect their lives and express and debate different opinions.

Follow-up: Students can write an 500-word editorial on the topic expressing their views and send it to NewsHour Extra [extra@newshour.org] for possible publication.

Evaluation: Students are graded on their answers to reading comprehension questions and/or their editorial.

Story: NASA's Historic Deep Impact Mission Reveals Secrets of Comets, 07/11/05
http://www.pbs.org/newshour/extra/features/july-dec05/deepimpact_7-11.html

Initiating Questions:

1. What are comets?

2. How did the sun and planets form?

3. What does NASA do? What are some famous NASA missions?

Reading Comprehension Questions: (click here for printout)

1. What is the design of the Deep Impact spacecraft?

The Deep Impact spacecraft had two parts -- a flyby craft equipped with high resolution imaging instruments and an 820-pound copper "impactor" to strike and leave a crater on the comet.

2. What happened when the impactor hit the comet?

On impact, Tempel 1 gave off light six times brighter than expected before expelling an unexpectedly large cloud of gas and ice, which blocked scientists' view into the comet's crater.

Scientists estimate the crater is larger than a house and possibly the size of a football field.

Mission members must wait for the cosmic dust to settle, allowing a clear view into the comet's interior.

The flyby craft was able to transmit real-time photos of the crash. The Hubble Space Telescope also captured a series of dramatic photos.

3. What has initial analysis of mission images revealed?

Initial analysis of collision images by mission scientists indicates that the comet, shaped like a pocked, lumpy potato, has a soft, powdery surface beneath which lies ice and trapped gas.

Other researchers argue, however, that the spike in ultraviolet light points to a solid surface.

4. Why is the study of comets important?

"Comets are the leftover bits and pieces from the outer solar system formation process. So if we wish to understand the initial conditions from which the outer solar system formed, the chemical mix and the structure of the particles that came together to form Jupiter, Saturn, Uranus and Neptune, then we'd like to study comets because they haven't changed a great deal in the intervening four and a half billion years," mission scientist Donald Yeomans told the NewsHour.

"We're all made of cometary stuff. The carbon-based molecules in the water that make up our persons are all brought to the early Earth via comets."

Discussion Activity (more research might be needed):

1. What are some questions you have about the universe/solar system that don't yet have answers? What would you like to know about the universe?

2. Take one question or topic and design a NASA mission to explore that question. Describe the mission's goals, equipment, and process.

Write a 300-500 word essay on any of these topics providing clear examples. Send your completed editorial to NewsHour Extra [extra@newshour.org]. Exceptional essays might be published on our Web site.