r t228 years.
So if Pluto really is a planet, it is certainly an odd one. It is very tiny: just one-quarter of 1percent as massive as Eart it doop of ted States, it quite y-eigates. t extremely anomalous; it means tour planetary system consists of four rocky inner planets, four gassy outer giants, and a tiny,solitary iceball. Moreover, to suppose t o findotion of space. terCy spotted Pluto’s moon, astronomers began to regard t section of ttentively and as of early December 2002 ional trans-Neptunian Objects, or Plutinos as ternatively called. One, dubbed Varuna, is nearlyas big as Pluto’s moon. Astronomers nos. ty is t many of typically tiveness, of just 4 percent, about t four billion miles away.
And exactly? It’s almost beyond imagining. Space, you see, is justenormous—just enormous. Let’s imagine, for purposes of edification and entertainment, t to go on a journey by rockets go terribly far—just to tem—but o get a fix on a smallpart of it we occupy.
No be t, it ake seven o get to Pluto. But of course travel at anyt speed. e’ll o go at ther more lumbering.
t speeds yet ac are t, ty-five thousand miles an hour.
t ember1977) Jupiter, Saturn, Uranus, and Neptune o use a “gravity assist” tec to t in a kind of cosmicversion of “crack t took to reacocross t of Pluto. t if until January 2006 (entatively sco depart for Pluto) akeadvantage of favorable Jovian positioning, plus some advances in tec tting ake rat allevents, it’s going to be a long trip.
No to realize is t space is extremely ful. Our solar system may be t trillions of miles, butall tuff in it—ts and tumblingrocks of teroid belt, comets, and oting detritus—fills less trilliont none of tem ely drao scale. Most scs ss coming one after t neigervals—ter giants actually castsrations—but t to get tune in reality isn’t just a little bit beyond Jupiter, it’s er—five times farter ter is from us, so far out t itreceives only 3 percent as muc as Jupiter.
Sucances,