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A printable worksheet for the lesson The journey from the asteroid belt (Adult). It prints on A4 without the website around it. The answers are on a separate sheet for the teacher.

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Adult · Adults; no background neededHowardites worksheet

The journey from the asteroid belt

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Key words

Meteorite
A meteorite is a piece of space rock that has survived its fall through the air and landed on Earth.
Jupiter
Jupiter is the largest planet in the Solar System, whose gravity shapes the asteroid belt and steers meteoroids towards Earth.
Asteroid belt
The wide ring of space between Mars and Jupiter where most known asteroids travel around the Sun.
Ceres
The largest object in the asteroid belt, about 940 kilometres across, classed as a dwarf planet since 2006.
Yarkovsky effect
A tiny thrust on a spinning asteroid caused by it giving off absorbed sunlight as heat in a slightly lopsided direction.
Isotope
One of two or more forms of the same chemical element whose atoms have different numbers of neutrons, and so different masses.

Choose the right answer

Circle the letter of the right answer.

  1. A group's exposure ages are spread evenly from 2 to 60 million years, with no clusters. What does that suggest?
    • AMany separate collisions released its pieces
    • BIts pieces never travelled through space at all
    • COne collision released all its pieces
    • DAll its pieces fell on the same day
  2. Many meteorites of one group have almost the same exposure age. What does this suggest?
    • AOne collision released them all at once
    • BThey all landed on Earth on the same day
    • CThey all formed when the Sun formed
    • DThey were all thrown off Mars
  3. Which event usually starts a meteoroid's cosmic-ray exposure clock?
    • AThe formation of the Solar System
    • BThe collision that broke it off as a small fragment
    • CIts discovery by a meteorite hunter
    • DIts entry into Earth's atmosphere
  4. Once a fragment is in a resonance, roughly how long does Jupiter take to stretch its orbit across Earth's path?
    • AAbout ten years
    • BAbout a million years
    • CAbout a hundred years
    • DAbout a billion years
  5. What does the Yarkovsky effect need in order to work?
    • AA body sitting right next to Jupiter
    • BA body made mostly of iron
    • CA spinning body absorbing sunlight
    • DA body that contains frozen ice

True or false?

Is the answer given right? Tick True or False.

  1. Which orbital period would place an asteroid in a resonance with Jupiter?

    Answer given: Exactly one third of Jupiter's period TrueFalse

  2. The Yarkovsky push is tiny. Why can it still move a fragment a long way?

    Answer given: It acts for millions of years and adds up TrueFalse

Write your answer

Answer in a word or a short sentence.

  1. Why do the members of an asteroid family travel on similar orbits?
  2. How is a cosmic-ray exposure age actually measured?
  3. Which isotopes does the lesson give as examples of those made by cosmic rays?

Task

Visit the asteroids section of this site and look up Vesta and one asteroid of your choice. Note where each orbits and how big it is. Then write a few sentences describing the journey of a fragment from Vesta to Earth, using the words collision, Yarkovsky effect, resonance and exposure age.

Howardites · free to copy for use in your classroom · answers are on the separate teacher's answer sheet