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Only the ones that are visible to the naked eye were discovered until Uranus was discovered in 1781 by William Herschel using a telescope in a systematic search of the sky. Uranus is theoretically just visible to the naked eye but no-one had noticed it. Neptune is dimmer by 2-3 magnitudes.
What else can I help you with?
When were vacuoles discovered?
Vacuoles were discovered between the late 1600's and early 1700's.
When was the walrus discovered?
Adolf Hitler discovered the walrus in the late 1700's. It is not sure as of when or where, but we know...he did it.
Where was the planet Mars discovered?
in the late 1600'S
Which empire had been steadily declining since the late 1700's?
the ottoman empire
When is radioisotopes discovered?
Radioactivity was discovered in the late 19th century. Radioisotopes have been discovered ever since then.
When was fluorine invented?
Fluorine was discovered in the 1500's. Flourine is used to make hydrofluoric acid and hydrofluoric acid was invented in the late 1700's.
Who discovered the island of Hawaii?
Well, James Cook got there in the late 1700's, but early Polynesians arrived in Hawaii almost 1000 years ago.
What was the approximate population of Maine in the late 1700's?
Maine at that time was part of Massachusetts. In the late 1700's the population of Massachusetts was about 280,000.
When did anarchy being?
in the late 1700's
When did slavery in the south begin?
Slavery began in the late 1600's and early 1700's. It became more prominent in the late 1700's.
Since the late 1700 the Mississippi River has been a vital waterway because it?
provided farmers and merchants an outlet to the Gulf of Mexico.
What year did Galileo see the planet mercury?
Galileo first observed the planet Mercury through his telescope in 1610.
