Passage Two: Questions 23-30
Hailey's comet has become the best23comet in history, but the informationthat has beengathered is only the beginning of what is needed to understandthiscomer, one of the mostprimitivebodies in the 24system. During the recentappearance of Hailey’s comet, a researchcorps of over 1000 professional25gathereddataaround the world. The datarevealed26 new information. For the firsttimeever, European and Sovietspacecrafthavephotographed the comet’s 27. . The photographs now show the mass of dirty ice
and gas thatmakes up the comet’s center.
In spite of close-up photosrevealing one of the oddest-Iookingobjects in the solarsystem, cometscientistsstill can’t decide how fastHailey’s nucleusspins. Someexpertsbelieve it spinsonceevery 2.2 days, somedetermine the spin to be once in 7.4 days, and otherscientistssuggestthat the comet28bothmotionssuperimposedtogether.
Astronomers29Haileyeachtime it comescloseenough to the earth, so that we can see the brightcloud of 30 dust and gas thatforms its tail. It is easiest to get a clearlook at the cometwhen it is far awayfrom the sun so that its activitydiesdown.
【題組】24. (A) singular (B) solar (C) lunar (D) stellar