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Dim lights glowed in the cabin. Brenn and Dara had switched on the artificial gravity and fallen asleep. They were startled awake by SAM's voice. "Become alert now. The ship nears Mercury. The arc of approach will permit excellent photos of the Sun. Retrieve the star camera for this task."
Brenn sat up to look out the window, but a shade slid quickly over it and snapped shut. "Never look directly at the Sun," commanded SAM, "for it can blind you. The famed human astronomer Galileo was blinded by looking at the Sun through a telescope.
"Know that the Sun is a star of medium size, located 93,000,000 mi (150,000,000 km) from Earth. Temperatures reach 10,000°F (5,500ü ¬ÀC) on the star's surface and 27,000,000¨°F (15,000,000°C) at its core. The Sun makes energy from nuclear explosions in its core, using over 4,000,000 tons of hydrogen each second. This star will probably continue burning for five billion more years.
"Raise shields for the ship. The Sun is a huge ball of boiling gases. Eruptions from the surface can sometimes reach out 500,000 mi (800,000 km) into space. The Sun is smaller than many other stars, but more than 1,000,000 times the size of Earth. "The Sun has strong gravity. If you could stand on its surface, you would weigh 28 times your Earth weight. This gravity holds all the planets in our solar system in orbit, so they do not fly off into space. The Sun rotates on its axis and revolves around our galaxy. One revolution takes about 225,000,000 years."
Dara gulped. How could she and Brenn take pictures of the Sun if they must not look at it? She thought about the heat-resistant spacesuits, the robotic arm, and the crewed maneuvering units. Brenn opened a tool cabinet. "Let's get to work," he said.
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QUESTIONS
Complete the sentences below.
1. The Sun is a _______________ of medium size.
2. The Sun is very hot. Temperatures reach _____________________ on its surface and _______________________ at its core.
3. The Sun makes energy from ________________________________ in its core.
4. The Sun is over ______________________ times as large as Earth.
5. If you could stand on the Sun, you would weigh ____________ times your Earth weight.
6. The Sun ____________________ on its axis and ________________________ around our galaxy.
7. Never look directly at the Sun, for it can ___________________ you.
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Writing Assignment: Help Brenn and Dara brainstorm a way to get pictures of the Sun. On the back of this sheet, write them a letter suggesting how they might get the job done. Don't forget to suggest ways they can keep themselves and the ship safe as they travel close to the Sun.