Howardites

A printable worksheet for the lesson The classification framework (Start here: Expert). It prints on A4 without the website around it. The answers are on a separate sheet for the teacher.

Answer sheet for teachersBack to the lessonAll worksheets

Start here: Expert · AdvancedHowardites worksheet

The classification framework

Name:Class:Date:

Key words

Meteorite
A meteorite is a piece of space rock that has survived its fall through the air and landed on Earth.
Classification
Classification is the process of identifying exactly what kind of meteorite a specimen is and giving it an official type and group.
Isotope
One of two or more forms of the same chemical element whose atoms have different numbers of neutrons, and so different masses.
Parent body
The asteroid, moon or planet that a meteorite was originally part of before it was knocked off into space.
Chondrite
A chondrite is a stony meteorite full of tiny round grains called chondrules, and almost unchanged since the Solar System formed.
Clan
A clan is a set of meteorite groups that share important features and probably formed in neighbouring regions.

Choose the right answer

Circle the letter of the right answer.

  1. At the top level of the modern scheme, where do iron meteorites sit?
    • AWith primitive achondrites, as partial melts
    • BWith chondrites, as undifferentiated material
    • CWith achondrites, from differentiated bodies
    • DIn a separate branch defined by metal content
  2. Why can equilibrated ordinary chondrites often be classified without oxygen isotopes?
    • AThey are always witnessed falls with known orbits
    • BTheir mineral compositions are diagnostic
    • CTheir parent bodies are known from spacecraft visits
    • DThey contain no oxygen-bearing minerals at all
  3. A newly found meteorite has a total mass of 60 g. What is the minimum type specimen?
    • A12 g
    • B60 g
    • C6 g
    • D20 g
  4. Why must the members that define a group be unpaired?
    • APaired stones by definition come from different bodies
    • BPaired stones are always too weathered to analyse
    • CPaired stones are one fall, not independent samples
    • DPaired stones are not allowed to receive official names
  5. A grouplet has four unpaired members, and a fifth unpaired member is found. What can follow?
    • AIt can be defined as a group
    • BIt is promoted to a clan
    • CIts members become ungrouped
    • DIt must stay a grouplet until it has ten

True or false?

Is the answer given right? Tick True or False.

  1. Why is pairing so important in Antarctic and desert meteorite research?

    Answer given: One fall can yield many separately found stones TrueFalse

  2. Which information must a classification submission include?

    Answer given: The sale price and the name of the buyer TrueFalse

Write your answer

Answer in a word or a short sentence.

  1. Three unpaired meteorites share properties consistent with one parent body. How are they classed?
  2. How are most carbonaceous chondrite groups named?
  3. In a classification tree, which three first branches follow the modern scheme?

Task

Draw a tree diagram with chondrites, primitive achondrites and achondrites as the first branches, then add classes, clans and groups. Place each meteorite named in this course on its branch.

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