International Astronomy Day

International Astronomy Day is a holiday that is celebrated not once during a calendar year but twice a year – once in spring and once in fall. The springtime celebration falls on the Saturday closest to the first quarter moon (which is around April or May).

The fall-time celebration of this holiday falls on the Saturday closest to the quarter moon (which is around September or October). The purpose of this holiday is not only to celebrate astronomy and all of its contributions to society but also to bring the general public together with astronomy professionals and groups.

History of International Astronomy Day

This holiday was created by Doug Berger in 1973 – the president of the Astronomical Association of Northern California at the time. He created International Astronomy Day in hopes that it would raise the interest of the general public in the field of astronomy and also give ordinary citizens an opportunity to use specialized astronomical equipment they would ordinarily not be able to use.

His original holiday, however, only included a spring celebration. There simply wasn’t a fall celebration. This was changed in 2007 though so International Astronomy Day could be celebrated both in the spring and in the fall.

While International Astronomy Day was created in 1973 and amended in 2006, astronomy itself goes all the way back to antiquity. In fact, it is one of the oldest natural sciences in the entire world.

Originally, astronomy and astrology were one and the same and had their origins in not only calendrical and cosmological systems but also in religious and mythological beliefs. And it would remain so for many thousands of years, right up into the 17th century.

This is when astronomy and astrology disentangled and became two separate systems. Astronomy became a methodical, scientifically driven medium to study the heavens, and astrology remained rooted in mythology.

Celebrating International Astronomy Day

There are a number of different ways to celebrate this holiday. You can attend one of the many International Astronomy Day events that are held all over the world and rub elbows with fellow astronomical enthusiasts, as well as groups and professionals in this field.

Or, if you don’t want to do that, then you can simply spend the day checking out the heavens on your own or with your family. Another great way to celebrate the holiday is to introduce your children to the wonderful world of astronomy or study astronomy on your own.


International Astronomy Day is not only a great day for people to reconnect with the universe and learn more about this field of scientific endeavor but it is also a good time for people to get together with friends and family and enjoy the heavens together.

When is it?
This year (2024)
Next year (2025)
Last year (2023)
Hobby & Creativity, Science