Launched by NASA in 1977, Voyager 1 and 2 have explored the giant outer planets
: Jupiter, Saturn, Uranus, and Neptune (see diagram, below).
and a is in units of the earth-Sun distance For the outer planets
, each planet is predicted to be roughly twice as far away from the Sun as the previous object.]
Your ruling planet Saturn is not the slowest of the outer planets
which orbits our solar system.
Pioneer 10 and the Voyager probes have toured the outer planets
, sending back a wealth of images and data.
In a move toward exploration of the outer planets
, scientists are working on building lighter, smaller probes.
Mark Littmann's Planets Beyond (04863436020, $19.95) republishes the updated, revised 1990 edition to survey the outer planets
; from the history of their discovery to modern scientific findings about the planets including Voyageur results.
We're 500 years in the future, following a war in a newly colonized solar system that was won by a coalition called the Alliance; the losers, the Independents, roam the outer planets
like frontier cowboys, along with the Reavers, thugs who eat their enemies live.
The moon's ample supply of helium-3, long touted by space buffs as a potential fuel for advanced fusion reactors, is duly noted, as are the even larger supplies of the substance in the atmospheres of all of the giant outer planets
. Jupiter and Saturn present particularly daunting prospects for exploitation, Lewis acknowledges, since their powerful gravitational fields would require any departing vehicle to have an extremely high escape velocity.
"TOI 270 is perfectly situated in the sky for studying the atmosphere of its outer planets
with NASA's future James Webb Space Telescope," the study's co-author Adina Feinstein of the University of Chicago said.
The inner, middle, and outer planets
are 3.1, 7.0, and 4.7 times the size of the Earth, and take 49, 87, and 303 days, respectively, to orbit around their suns.
The episode recalled those heady days in the mid-1960s when NASA's deep thinkers envisioned dispatching probes on a "Grand Tour" of all the outer planets