Observatory Icon

Solar Observing
Take a look at the sun through our historic Zeiss refracting telescope and learn more about telescopes and astronomy. (Weather Permitting)

The observatory is named in honor of Joel N. Bloom, who was director and president of The Franklin Institute from 1969 until 1990.

Visit the Joel N. Bloom Observatory for a bit of stargazing on the rooftop! Our instruments, including the 10-inch Zeiss refractor and four Celestron CPC 800 GPS Computerized Telescopes, and 8" Schmidt-Cassegrain models, provide views of most planets and bright stars, several star clusters and nebulae, and a few galaxies. On a clear day, you may be able to see sun flares and spots, and at times, the moon!

Open daily (weather permitting), the Joel N. Bloom Observatory is operated and maintained by The Franklin Institute's Chief Astronomer Derrick Pitts and staffed by a staff of knowledgeable volunteers. It is one of a handful of observatories in the country to provide optically-safe, real-time, direct observation of solar activity such as flares and prominences.

Things to Do and See at the Observatory

  • Chief astronomer Derrick Pitts educating in the Joel N. Bloom Observatory on the roof of The Franklin Institute.
    Stargaze with 10-inch Zeiss Refractor Telescope

    Planets, stars, star clusters, nebulae, and a even few galaxies await!

  • A young boy looking through the sunspotter telescope in The Franklin Institute's Observatory.
    Visit the nearest star—Our Sun

    See what real sunspots and flares look like without the need for shades!

  • The Franklin Institute's telescope trained on a planet above the Philadelphia skyline.
    Travel through our Solar System

    Jupiter, Saturn, Mars, and Venus are often stops on this interplanetary tour!

Interactive Map

Floor

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Map of the fourth floor, showing the location of the Observatory.
Map of the fourth floor, showing the location of the Observatory.