Administration: Individual. The DAB-4 is a revision of one of the most popular individual achievement tests available. Its 8 subtests identify studentsâ strengths and weaknesses across important areas of school achievement. A supplemental manual shows how to probe student responses to obtain information about studentsâ thinking processes and problem-solving strategies.
In 1992, the first evidence of a planetary system other than our own was discovered, orbiting the pulsar PSR B1257+12. Three years later, 51 Pegasi b, the first extrasolar planet around a Sunlike star, was discovered.
William Herschel noticed while surveying stars that one object moved apart from the star background. It was the first planet discovered since ancient times. March 13, 1781. The 7th planet â Uranus â was discovered on this date, completely by accident. British astronomer William Herschel was performing a survey of all the stars that were of magnitude 8 â in other words, too faint to see with the eye â or brighter.