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Finding Neptune With Pencil and Paper

6th grade nonfiction passage about the discovery of neptune: 241 words, six questions, an answer key and vocabulary.

6th grade nonfiction the discovery of neptune 241 words

Finding Neptune With Pencil and Paper

Uranus was found in 1781, and astronomers soon began to track its path around the sun. They used the laws of gravity to predict where it should be on any given date. But as the years went by, Uranus kept drifting away from the predictions. It was a little ahead in some years and a little behind in others.

Some scientists decided the planet was not to blame. They suspected that the pull of another, unseen planet was tugging on Uranus. If that was true, the new planet had to be farther out, and its gravity would be changing the way Uranus moved.

Two mathematicians, one in France and one in England, each worked on the problem separately. They had no telescope. They used pencils, paper and many long calculations to work backward from the odd motion of Uranus. Their goal was to find where a hidden planet would have to be to cause it.

In 1846, the French mathematician sent his answer to astronomers in Berlin. The observers pointed their telescope at the predicted place on the very first night they received the letter. Within about an hour, they spotted a faint point of light that was not on their star map. It was a new planet, now called Neptune, and it was very close to where the math said it would be.

Neptune is too dim to see with the unaided eye. Its discovery showed how powerful careful reasoning can be.

Questions

  1. In what year was Uranus found? in the text

  2. What was strange about the way Uranus moved? in the text

  3. What did some scientists suspect was tugging on Uranus? in the text

  4. What tools did the two mathematicians use? in the text

  5. Why did the astronomers in Berlin point their telescope at one spot? think about it

  6. Why is it impressive that the planet was found near the predicted place? think about it

Words to know

predict
to say what will happen before it does
gravity
the pull that objects have on each other
calculations
steps of math used to find an answer
mathematicians
people who work with numbers and equations
faint
weak or hard to see
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One passage, three levels

The same topic and facts written three ways, so a mixed class can read and talk about one text. Each group’s sheet shows only a shape; the key says which is which.

● Easier · 217 words · Flesch-Kincaid grade 3.7

Uranus was found in 1781. Soon, astronomers began to track its path around the sun. They used the laws of gravity to guess where Uranus should be on any date. But Uranus did not follow the guesses. Some years it was a little ahead. Some years it was a little behind.

Some scientists said the planet was not to blame. They thought another planet was tugging on Uranus. That planet had to be unseen. It had to be farther out. Its gravity would change how Uranus moved.

Two mathematicians worked on the problem. One lived in France. One lived in England. They worked on their own. They had no telescope. They used pencils, paper and long calculations. They worked backward from the odd motion of Uranus. They wanted to find where a hidden planet would have to be.

In 1846, the French mathematician sent his answer to astronomers in Berlin. The astronomers aimed their telescope at that spot on the first night. In about an hour, they saw a faint point of light. It was not on their star map. It was a new planet. We call it Neptune. It was very close to where the math said it would be.

Neptune is too dim to see with just your eyes. Its discovery showed the power of careful thinking.

▲ This passage · 241 words · Flesch-Kincaid grade 6.9

Uranus was found in 1781, and astronomers soon began to track its path around the sun. They used the laws of gravity to predict where it should be on any given date. But as the years went by, Uranus kept drifting away from the predictions. It was a little ahead in some years and a little behind in others.

Some scientists decided the planet was not to blame. They suspected that the pull of another, unseen planet was tugging on Uranus. If that was true, the new planet had to be farther out, and its gravity would be changing the way Uranus moved.

Two mathematicians, one in France and one in England, each worked on the problem separately. They had no telescope. They used pencils, paper and many long calculations to work backward from the odd motion of Uranus. Their goal was to find where a hidden planet would have to be to cause it.

In 1846, the French mathematician sent his answer to astronomers in Berlin. The observers pointed their telescope at the predicted place on the very first night they received the letter. Within about an hour, they spotted a faint point of light that was not on their star map. It was a new planet, now called Neptune, and it was very close to where the math said it would be.

Neptune is too dim to see with the unaided eye. Its discovery showed how powerful careful reasoning can be.

■ Harder · 254 words · Flesch-Kincaid grade 9.8

Uranus was discovered in 1781, and astronomers promptly began tracking its path around the sun. They relied on the laws of gravity to predict where the planet ought to appear on any given date. As the years passed, however, Uranus persistently strayed from those predictions, running slightly ahead of schedule in some years and slightly behind in others.

Certain scientists concluded that the planet itself was not at fault. They suspected that the gravitational pull of another, unseen planet was tugging on Uranus. If that were true, the new world had to lie farther out, and its gravity would be altering the way Uranus traveled.

Two mathematicians, one in France and one in England, tackled the problem independently of each other. Neither of them had a telescope. Armed with pencils, paper and an enormous number of lengthy calculations, they worked backward from the odd motion of Uranus. Their goal was to determine where a hidden planet would have to be in order to cause it.

In 1846, the French mathematician mailed his answer to astronomers in Berlin. On the very first night after the letter arrived, the observers pointed their telescope at the predicted location. Within about an hour they spotted a faint point of light that did not appear on their star map. It was a new planet, now called Neptune, and it was remarkably close to the place that the mathematics had indicated.

Neptune is too dim to be seen by the unaided eye, and its discovery demonstrated the extraordinary power of careful reasoning.

Download as one PDF

How to use it

  1. Press Read it big (or B) to put the text on the projector, or Full screen (F) to fill the whole screen.
  2. Ask the questions one at a time and use Show answer when the class has decided. A shows or hides every answer.
  3. Print student copy for the class, or Print with answers for yourself.

Ideas for class

  • Before reading, put predict, gravity, calculations, mathematicians and faint on the board with their meanings from the Words to know section and have students predict what the text will be about.
  • Read it aloud once while students follow along, then have them reread it alone or with a partner. At a calm 100 words a minute it takes about 2 minutes to read aloud.
  • Use the Read it big button (or B) to put the text on the projector, and Show answer on one question at a time so the class commits to an answer first.
  • Question 5 asks the reader to infer. Ask students to point to the words in the passage that led them to their answer.
  • Ask students to write one question the passage did not answer, then look for the answer in a book or on a classroom screen.
  • Print the student copy for independent work and keep the answer-key copy for yourself.

Related

Questions

What reading level is "Finding Neptune With Pencil and Paper"?

It was written for 6th grade. It has 241 words and works out to a Flesch-Kincaid grade level of about 6.9. That is a formula's estimate from sentence length and syllables, and it is not a Lexile or a guided reading level, so check it against your students.

What do the questions ask?

There are six. 4 ask for something the text says directly and 2 ask the reader to work something out from clues. Each has an answer in the key, and the answers are written as a teacher would accept them, not as the only possible wording.

How long does it take to read?

About 2 minutes read aloud at 100 words a minute. For a one-minute fluency check, paste it into the fluency timer and use the word count.

Can I print it?

Yes. Print student copy gives the passage, the questions with lines to write on, and the word meanings. Print with answers gives the same page with the answers filled in. Both are made in your browser.

Is this passage from a published book?

No. It was written for Peabody Teach, so there is no book to buy and no login to read it.

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