This is an article I wrote many years ago about reproducing the
discovery observation of Uranus by William Herschel. I have adapted it
for use with SkyTools.

Scenario: Georgium Sidus
Location: Bath England, 51:22N 2:22W, Sky Br. "Far away from Lights"
Date/Time: 1781 March 13 21:00
Target: Uranus
Telescope: 8 inch reflector

Add Bath as an observing location, and if you want, create an 8-inch
reflecting telescope. Open a Naked Eye Chart and set up the date, time
and location. Set Uranus as the target object.

This is the sky as it appeared on that night to Herschel. Try turning
the constellation lines off and perhaps adjusting the star size smaller
for the most realistic effect.

On a march evening in 1781, Frederick William Herschel made a discovery
that would raise his stature from that of an obscure musician to famous
astronomer. He stood near his home in Bath England, peering through a
7-foot long Newtonian telescope of his own making at the stars within
the triangle formed by 1 Gem, Elnath, and Zeta Tau. One of them seemed
different.

He would later record, "In examining the small stars in the neighborhood
of H Geminorum I perceived one that appeared visibly larger than the
rest; being struck with its uncommon appearance I compared it to H
Geminorum and the small star in the quartile between Auriga and Gemini,
and finding it so much larger than either of them, I suspected it to be
a comet."

Switch to the Interactive Atlas. Zoom to about a 4-5 degree FOV. Open
the Context Viewer and select a telescope (an 8-inch if you have it).
Now position the Context Viewer in a corner, sized to about 1/4 that of
the Atlas window. Starting at 1 Gem on the Atlas, drag the FOV circle
from star to star as Herschel did. For best results set planets to
display as stars when zoomed out (Misc tab on the Charts Prefs).

In the months that followed it became apparent that this was no comet,
but rather the first planet discovered in historical times. The planet
he discovered, which he later named Georgium Sidus after the king who
appointed him as royal astronomer, orbited nearly twice as far from the
sun as Saturn. His name didn't catch on, and for a brief time the planet
was known simply as Herschel. Eventually Elert Bode's suggestion of
Uranus was adopted because it was more in line with the traditional
names of the planets.

Close the Context Viewer and set the time step on the atlas to 1 day.
Time step ahead to see where Uranus appeared on subsequent nights.

Herschel's discovery was by no means an accident. He and his brother
Alexander built the largest telescopes of the day--the first practical
application of the reflecting telescope invented by Newton. Assisted by
his sister Caroline, Herschel set out to observe every star in the sky.
A he put it, "In a regular manner I examined every star in the heavens
and that night it was its turn to be discovered." Biographies are full
of stories that reflect his great zeal for observing, including slipping
out between the acts of a play.

Uranus is often brighter than 6th magnitude, which makes it just barely
visible to the unaided eye. It's a wonder that no one had discovered it
before. Although Uranus had been recorded as a star, apparently its slow
motion through the sky allowed it to go undetected as a planet.

Herschel also discovered two of the moons of Uranus, Oberon and Titania,
with his 20-foot long telescope on January 11, 1787. By this night six
years later Uranus had moved up the left "twin" to a position to the
east of Pollux.

If I close my eyes and listen carefully, I can almost hear the Herschel
family gathered inside the 40-foot tube of his largest telescope
singing, Merrily, merrily let us all sing, And make the old telescope
rattle and ring. Can you?

Happy armchair observing.

Greg

--
Greg Crinklaw
Astronomical Software Developer
Cloudcroft, New Mexico
skyhound.com