January 7th, 1610: Galileo Observes the Satellites of Jupiter

By Cavendish, Richard | History Today, January 2010 | Go to article overview

January 7th, 1610: Galileo Observes the Satellites of Jupiter


Cavendish, Richard, History Today


The telescope is derived from the pairs of spectacles with glass lenses which were made in medieval Europe to enable people to see further and more clearly than they could without them. By 1608 the first spyglasses had appeared and a Flemish spectacle-maker in Holland who applied to the States General for a patent on an 'instrument for seeing far' was quickly challenged by two other Dutch spectacle-makers, who submitted their own claims. Early in 1609 word of the new devices reached the professor of mathematics at Padua University in the Republic of Venice.

[ILLUSTRATION OMITTED]

His name was Galileo Galilei and he was in his mid-forties when he heard from the influential Venetian humanist Paolo Sarpi that a Dutchman was on his way to Venice hoping to sell one of the new instruments to the doge, Leonardo Dona. Galileo was immediately galvanised and asked Sarpi to caution the doge and the Venetians not to accept a device from anyone else until he could show them a better one of his own. Sarpi did as he was asked and Galileo worked frantically trying out different pairs of spectacle lenses fixed into a wooden tube, grinding his own lenses until he worked out an effective arrangement. He quickly improved on his first instrument and the one he and Sarpi demonstrated to the doge in August worked far more effectively than any of its predecessors.

Galileo and Sarpi took Doge Dona and his advisers to the top of the tower of St Mark's and pointed the new telescope towards Padua. The doge was astounded to be able to see the tower at the centre of the city more than 50 kilometres away. After gazing across Venice itself, they looked far out into the Adriatic where the Venetians saw ships that would not be visible to the unassisted eye for another two hours or more. The party returned to the doges palace and, far from demanding a high price for his invention as expected, Galileo shrewdly offered the telescope to Venice as a gift. The present was eagerly accepted and Galileo went away with his salary at Padua almost doubled and a lifetime tenure in his post.

Galileo and Sarpi had taken care to stress the military advantages of the telescope. In his letter to the doge confirming his gift, Galileo drove home the point that the new instrument would enable Venetian ships at sea to discern the strength of an enemy fleet at a far greater distance than before and similarly allow an army on land to look inside distant strongholds and watch the movements of enemy troops from much further away. …

The rest of this article is only available to active members of Questia

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited article

January 7th, 1610: Galileo Observes the Satellites of Jupiter
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    Buy instant access to save your work.

    Already a member? Log in now.

    Author Advanced search

    Oops!

    An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.