Voyager demos

1. Moon -- 180 deg -- 2:30 16 Sept. --

Rose 2 hr ago, i.e. when sun at high noon

just passed between Mars and Pluto

in Sagittarius (zody const.)

zoom -- not quite to 1st quarter

back to 180 zoom -- go forward 2 days -- crosses ecliptic 20 Sept. not new or full so no eclipses

 

2. Jupiter 10:30 PM 16 Sept. to east -- 120 deg

rose 2.5 h ago -- Saturn trailing ~ 1 h

-2.4 mag, easily visible -- center and zoom

4 Galilean satellites -- all in a line -- aligned with ecliptic, also Jupiter’s equator

Galileo saw this first -- followed their orbits -- supported Copernican idea that earth orbits sun

picture HST scars from Shoemaker Levy

5th picture, only clear view of impact (million megaton) from Galileo spacecraft

 

unzoom and center on Saturn -- 1st mag

zoom in -- rings are also aligned with ecliptic. Saturn tilted 20 deg, like earth

4th picture -- best from Voyager -- 3 small satellites and one shadow (solar eclipse!)

 

3. Venus -- 5 AM -- rose about 2 h ago -- -3 mag -- brighter than alpha Canis Majoris (Sirius)

morning star

center and zoom in -- venus in crescent phase -- Galileo saw this and argued venus orbits sun

can see crescent with good binos

run 1d/step to see phases of Venus

venus gets smaller and more full -- further from Earth

Full phase -- on opposite side of sun from earth

waning gibbous -- venus gets larger -- now an evening star

crescent, then crosses in front of sun (new phase)

stop May 2001 -- back to present phase (i.e. 1 synodic period

pic 1 -- clouds of Venus -- highly concentrated sulphuric acid drops

pic 2 -- surface of Venus venera -- bottom picture how it would look with white light ill.

pic 11 -- how venus would look if clouds removed (from radar reflections)

pic 15 -- elevations on venus from radar (not how it would look to eye)

 

4) planet orbits -- 50 AU above sun -- zoom 30 deg

indicate sun, merc, ven, earth, mars, jup, sat

turn stars on and off

run 1/day till Dec. 1999 -- one complete orbit of Merc.

fastest Merc., slowest Jupiter and Saturn

zoom 120 -- now can see Ur. Nep. Pluto

1month/step rotate till 2010

 

5) earth seasons seen from sun -- start today 16 Sept. -- near equinox -- sun near equator -- see earth equator on -- max heating at equator

v13 & 14 review

rotate 1 day at 10min/step day = night = 12 h

1 day/step till Dec. 22

Now can see S. Pole. Rochester is NOT well illuminated

run for 1 day at 10 min/step

1 day/step till March 22 -- equinox again

till Jun2 22 -- now Rochester nicely illuminated -- summer

back to 16 Sept. -- again equinox