The Planets
Mercury
Most. elusive. of. the. five. bright. naked-eye. planets. is.
Mercury..This.is.due.to.its.proximity.to.the.Sun.in.the.
sky.(being.the.closest.planet.to.it.in.space).and.its.rapid.
orbital.motion.around.the.Sun.of.just.88.days..Mercury.
can.be.so.difficult.to.catch.that.it’s.claimed.some.famous.
astronomers. of. the. past. never. saw. it!. But. you. should.
have.no.trouble.doing.so.if.you’ll.make.the.effort.to.look.
in.the.right.place.at.the.right.time..It’s.typically.at.peak.
visibility. for. a. week. or. so. several. times. a. year,. either.
in.the.evening.sky.after.sunset.or.morning.sky.before.
sunrise..
Mercury. appears. in. the. twilight. sky. as. a. fairly. bright.
star,. not. far. above. the. horizon.. The.Astroscan’s. wide.
field. and. good. light-gathering. power. will. allow. you. to.
search.the.horizon.sky.and.find.the.planet.even.if.thin.
clouds,.city.haze,.light.pollution,.or.twilight.itself.make.
visual.detection.difficult..Mercury.may.look.almost.as.if.
it’s.under.water.with.its.image.shimmering.and.breaking.
into.little.bits.if.the.long,.low.atmospheric.viewing.path.
is.turbulent..But.if.you.get.a.period.of.excellent.seeing,.
its. tiny. disk. will. be. just. barely. visible. at. 30X,. while. at.
56X.you’ll.see.it.as.a.crescent,.half,.or.slightly.gibbous.
Planets in
Order of
Distance
from the Sun
Length
of Year
(Sidereal
Period)
Average Distance
from the Sun
in Miles
Mercury
87.90.days
36,000,000
Venus
224.70.days
92,957,200
Earth
365.26.days
141,600,000
Mars
686.98.days
141,600,000
Jupiter
11.86.years
484,300,000
Saturn
29.46.years
886,100,000
Uranus
84.01.years
1,783,000,000
Neptune
164.79.years
2,793,000,000
Pluto
247.76.years
3,666,000,000
phase.depending.on.where.it.is.in.its.orbit..In.addition.to.
the.two.astronomy. magazines. referenced.on.page.13.
which.give.the.positions.and.visibility.of.all.the.planets.
including.Mercury.each.month,.the.Scientifics’.Star.and.
Planet. Locator. included. with. your. telescope. provides.
the.same.information.in.condensed.form.for.all.five.of.
the.bright.naked-eye.planets.
