Review of I Wonder Why Stars Twinkle
Reviewed by: Marianne Dyson, June 27, 2003
This book contains a list of 30 astronomy questions with brief answers and sidebars. As I read the book, it quickly became obvious that the information was dated. For example, one sidebar states that "no other solar systems have yet been found." Over a hundred extra-solar planets have been discovered in recent years. The book lists Jupiter as having 16 moons, and the current National Science Data Center lists 60. Since this book was written, the "Big Crunch" Theory has been pretty much dismissed, hydrogen was found on the moon, water was confirmed on Mars, the speed limit went up from 55 mph to 70, the space toilet design changed (no seatbelts), Pluto again became the farthest planet, and NASA replaced the MMU with SAFER (a backpack worn by astronauts).
Besides the out-of-date information, there are misleading statements such as, "Ice cream would taste as hot as soup on Pluto..." This implies that the temperature of ice cream is somehow changed from below the freezing point of water to well above the freezing point just by being on Pluto. Ice cream placed on the surface of Pluto would quickly chill down even more to match the temperature of the surface. It certainly would not "taste" hot or be hot as stated in the text and shown in the illustration. I think the point that was trying to be made and missed, is that ice cream, if it were near the freezing point of water at first, would be the warmest thing (next to the human in the spacesuit!) on Pluto.
Another misleading statement is, "Rockets have to go faster than 7 miles (11 km) per second to get into space." The more accurate fact is that rockets have to go 7 miles per second to escape Earth's gravity. This is the speed required to go to the Moon. However, to go into space - defined as 50 miles above the surface of Earth, a rocket doesn't have to go that fast. To reach orbit, space ships have to go "only" 5 miles per second. Suborbital rockets can go even slower.
Finally, the last question, "Why do astronauts float in space?" is answered incorrectly. While it is true that "gravity is everywhere," it is not true that "Out there, the Earth's gravity isn't strong enough to hold them down..." At 200 miles above the surface of Earth, gravity is 90 percent what it is on the ground. If the astronauts stood on a bathroom scale at the top of a 200-mile-high tower, they would weigh almost the same as they did on Earth. They would NOT float. The reason they float is that they are falling. The faster an object moves, the farther it goes before gravity pulls it to the ground. This is why a bullet goes farther than a tossed ball. Spaceships go up and then go so fast (5 miles a second) that gravity pulls them in a circle around the planet. They continuously fall without hitting the ground. The whole time they are falling, they are weightless. Astronauts float in space not because gravity isn't strong, but because they are falling.
The book earns 1 point for readability, 1 for useful illustrations (I especially like the tug of war picture between the Earth and moon), only 1 of 2 for accuracy because of the gravity error, -1 for the unclear explanations, and -1 for out-of-date information. Total: 3 points. There are more accurate and up-to-date books out there. Rating: Be Careful.
Title: I Wonder Why Stars
Author: Carol Stott
Illustrator: Chris Forsey
Number of Pages: 32
Date: 1993, 1997, 2003
Retail Price: $5.95