This site uses cookies. By continuing to use this site you agree to our use of cookies. To find out more, see our Privacy and Cookies policy.
Skip to the content

Share this

Free weekly newswire

Sign up to receive all our latest news direct to your inbox.

Physics on film

100 Second Science Your scientific questions answered simply by specialists in less than 100 seconds.

Watch now

Bright Recruits

At all stages of your career – whether you're an undergraduate, graduate, researcher or industry professional – can help find the job for you.

Find your perfect job

Physics connect

Are you looking for a supplier? Physics Connect lists thousands of scientific companies, businesses, non-profit organizations, institutions and experts worldwide.

Start your search today


The day Galileo brought astronomy to the masses

One of Galileo’s first telescopes

By Michael Banks

Today marks an important date in the calendar of the International Year of Astronomy (IYA2009.

400 years ago, on 25 August 1609, the astronomer Galileo Galilei presented his first telescope to policy makers from the Venetian Republic.

Galileo ushered the lawmakers into St Mark’s Campanile – a bell tower in St Mark’s Square — in the heart of Venice to present his latest invention.

Impressed with seeing objects such as ships from a great distance, the telescope obviously left its mark as Galileo’s salary was doubled and he was also awarded life tenure at the University of Padua.

Galileo probably made a lot of cash from selling the telescope to merchants who found them useful at sea and as items of trade.

However, Galileo is, of course, best known for the mark he has left on the history of astronomy. (As always Google have their own tribute to the anniversary)

To mark the IYA2009, earlier this year we published an interesting article about how one of Galileo’s early telescopes was being rebuilt by researchers in Italy to study what Galileo may have been able to see.

Staff at the Institute and Museum of the History of Science in Florence, Italy, together with the Arcetri Observatory, also in Florence built an exact replica of the device that Galileo gave to his patron the Grand Duke of Tuscany, Cosimo II, in about 1610 that could magnify distant objects by up to a factor of about 20.

The Galileo anniversary is, however, not the only one in astronomy on this day.

Today also marks the 20th anniversary of NASA’s Voyager 2 craft coming closest to Neptune on its grand tour of the outer planets. (click here for the article we will be publishing in the September issue of Physics World about the anniversary)

The two Voyager craft — named Voyager 1 and Voyager 2 — launched on 5 September and 20 August 1977, respectively, (yes, the dates are the right way round) and completed their grand tour of the solar system 20 years ago.

Possibly one of the most successful space missions, the two craft are now on their way to the boundaries of the heliosphere – the ‘bubble’ of space blown by the solar wind into the interstellar medium.

So if you are feeling inspired by the Galileo anniversary and want to see for yourself what he could have observed 400 years ago, then you can always get your hands on your very own Galileoscope.

This entry was posted in General. Bookmark the permalink.
View all posts by this author  | View this author's profile


  1. Galileo. Written 1972
    This song has been around for awhile, and I think this is the fourth
    recorded version of it. Maybe fifth. To find out learning is fun.
    I guess that is the point.
    My kids who sang on this version, told me that now they know
    about Galileo because they memorized the lyrics to this song.
    I wondered if that could happen, way before my own children
    showed up, and low and behold, it could and did. There are a
    couple more of these type of tunes, as Galileo was originally
    part of a series. Get a real job Issac (Newton), and Socrates
    you’re a tease. (boom, splash:-)
    Here’s the rest of them!

  2. Gaina Alex

    I recollect a book which I have red about 40 years ago with a biography of Galilei. The principal achieving was concerning His famous law, that all the free falling bodies have the same acceleration g. But the construction of a telescope was not less important. Galileo was one of the men which moved the progress of the world by 7-miles steps.

  3. Giancarlo Truffa

    I found this info on Google and some newspaper. I don’t understand from where it started but, indeed the date is wrong.
    First presentation to Venetian Noblemen happened on Aug 21st 1609 and “official” presentation to Venetian Senate and government on Aug 24th.
    On Aug 25th Galileo received the confirmation of his position as teacher of mathematics in the University of Padua and his salary was increased to 1000 ducati.


  • Comments should be relevant to the article and not be used to promote your own work, products or services.
  • Please keep your comments brief (we recommend a maximum of 250 words).
  • We reserve the right to remove excessively long, inappropriate or offensive entries.

Show/hide formatting guidelines

Tag Description Example Output
<a> Hyperlink <a href="">google</a> google
<abbr> Abbreviation <abbr title="World Health Organisation" >WHO</abbr> WHO
<acronym> Acronym <acronym title="as soon as possible">ASAP</acronym> ASAP
<b> Bold <b>Some text</b> Some text
<blockquote> Quoted from another source <blockquote cite="">IOP</blockquote>
<cite> Cite <cite>Diagram 1</cite> Diagram 1
<del> Deleted text From this line<del datetime="2012-12-17"> this text was deleted</del> From this line this text was deleted
<em> Emphasized text In this line<em> this text was emphasised</em> In this line this text was emphasised
<i> Italic <i>Some text</i> Some text
<q> Quotation WWF goal is to build a future <q cite="">
where people live in harmony with nature and animals</q>
WWF goal is to build a future
where people live in harmony with nature and animals
<strike> Strike text <strike>Some text</strike> Some text
<strong> Stronger emphasis of text <strong>Some text</strong> Some text