Just Too Cool: a stamp … yes… a stamp

Some of you long-time readers know that I sometimes write about things astronomical and that I have mentioned the fascinating Jesuit mathematician Christopher Clavius (+1612), who worked out the reform of the calendar for Pope Gregory XIII.

For your Just Too Cool file, or at least for my Just Too Cool file, the Vatican Post has put out a stamp with none other than Christopher Clavius!

Here is a shot from the tomb of the aforementioned Roman Pontiff, depicting the moment Clavius presented his scheme for the reformation of the Julian calendar.

Clavius did all his calculations without the use of the decimal point!  The decimal point, or mark, was known at the time, but it wasn’t commonly used.  Clavius would pioneer it’s use in later work.

I think it is interesting that of all the things Gregory XIII could have selected for his monument, this is the moment.

BTW… note the guy to the far left, with the eye-glasses!

Clavius is one of many Jesuit mathematicians who have a crater on the Moon named after them.

About Fr. John Zuhlsdorf

Fr. Z is the guy who runs this blog. o{]:¬)
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  1. teomatteo says:

    Maybe the guy with the glasses was Clavius’s assistant. The solar observer.

  2. Bryan Boyle says:

    Now, there a Jesuit (among many in the sciences) that made a positive contribution! And immortalized in 2001. Wonder if he knew about the monolith?

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  4. RichR says:

    Astronomy and Popes.

    Right up your alley, Fr.Z!

  5. Tom Ryan says:

    I think nearly half of the moon’s craters are named after Jesuit scientists.

    Those were the days…

  6. pseudomodo says:

    It actually does look a lot like St. Philip Neri and his Spectacles!


  7. Gus Barbarigo says:

    Very neat, fun, post. On a another note, here’s another reason to keep in mind the Church’s gift to the world in the form of the Gregorian Calendar: the BBC dropped “anno Domini” and “Before Christ,” so as not to offend Muslims and to be “politically correct:”


    I see this rejection of Christ and this theft of the Gregorian Calendar more and more in books, articles, etc.

    I’ve protested BCE/CE (instead of BC/AD) on message boards, etc., and I encourage all of you to defend our Lord and our culture in this regard!

  8. irishgirl says:

    This IS cool, Father Z!
    @ Gus Barbarigo: I’ve noticed that recently when listening to the BBC World News Service on my radio overnight. Why are they so afraid of offending Moslems and being ‘politically correct’ (a lot of hogwash if you ask me), and denying the role of Christianity in forming the history of England and Europe? This makes me mad….!

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