Spotlight; Astronomer Frank Drake and The Drake Equation


Via SETI Institute

Astronomer Frank Drake, born in 1930, the same year Neil Armstrong was born, is one of the most famous and admired Astronomers of the late 20th century. He is best known for the ground breaking Drake equation but has also been involved in a number of other successful projects.


At a young age, Drake knew he was interested in science. As a young boy in Chicago, he frequently visited the Museum of Science and Industry where he became fascinated with an exhibit that showed the sun to be an average star among billions of others in the Milky Way Galaxy.

Furthermore, a Baptist upbringing, made him question religious fundamentalism and subsequently, wonder about the big questions, such as; Are there other intelligent civilizations out there?

As a young man and also curiously just like Neil Armstrong, Drake attended college on a Navy scholarship, where he intended on studying aerospace engineering but ultimately ended up majoring in Physics. He graduated with Honors from Cornell before paying his dues in the Navy, as an Electronics technician aboard the U.S.S. Albany.

After serving aboard the Albany, he enrolled in Graduate school at Harvard, where he began to make a name for himself. The department’s Chairman, put Drake’s electronic expertise to use by assigning him to work in radio astronomy. It seems fate was aligning events in Drake’s life for him to realize his life’s work; the legitimization of the study and search for extraterrestrial life.

After Harvard, Drake went to Green Bank, West Virginia and began work at the National Radio Astronomy Observatory. In secret, he and other colleagues began using Green Bank’s radio telescope, to search for alien transmissions in the cosmos. He called this search; Project Ozma.

Through Project Ozma, Drake met Cornell graduate student Carl Sagan, who obviously became the, celebrity scientist of the late 20th century.

Along with his and Sagan’s quest to legitimize the search for alien life, Drake’s contributions to Astronomy began to add up. Using the telescope at Green Bank, he was able to map the center of the Milky Way galaxy by analyzing the radio signals originating from the center.

He was able to deduce that Jupiter had radiation belts similar to Earth’s Van Allen belts, in which the charged particles of these belts, originally posed a challenge to the Apollo missions who would have to pass through them on their way to the moon.

While Carl Sagan originally theorized that the planet Venus might be a warm, tropical world, Drake figured out that Venus’s atmosphere was in fact as thick as an ocean on Earth and acted as a greenhouse, trapping all heat from leaving the planet’s surface.

He configured a method of assessing radio signals from the planet’s surface that eventually allowed for Venus’s geography and surface to be mapped. This method would later be used to help us map the surface of other world’s in our solar system.

But alas, it was in 1961 when Drake on a whim, while preparing the topics for a conference, came up with his revolutionary equation.

The equation has become a benchmark for SETI and has remained an icon in Astronomy.

N = R* • fp • ne • fl • fi • fc • L

N = The number of civilizations in the Milky Way galaxy whose electromagnetic emissions are available to detect.

R* = The rate of formation of stars suitable for the development of intelligent life.

fp = The fraction of those stars with planetary systems.

ne = The number of planets, per solar system, with an environment suitable for life.

fl = The fraction of suitable planets on which life actually appears.

fi = The fraction of life bearing planets on which intelligent life emerges.

fc = The fraction of civilizations that develop a technology that releases detectable signs of their existence into space.

L = The length of time such civilizations release detectable signals into space.


Along with being one of the principal founders of SETI, Drake’s career continued to skyrocket. He was involved with the study of a new type of star discovered in the mid 1960’s, called pulsars, which are remarkably ancient stars, many being tens of billions years old. They are unique in that they rotate extremely fast and emit pulses of electromagnetic radiation like a light house. Each pulsar’s spin can be determined to a unbelievable degree of accuracy and no two stars spin at the same rate. Drake is even said to be credited with coining the word ‘Pulsar.’

He went on to work on the Pioneer Plaques and The Golden Records, which serves as Humanity’s message in a bottle in the vast ocean that is interstellar space. He used pulsar stars to devise a map that he and Sagan installed on Voyager’s Golden Record. A map, that pinpoints the location of Earth using fourteen known Pulsars that connect to a central point; our sun.

The logic goes, that if other Intelligent beings know what Pulsars are, they would be able to locate Earth by decoding the spin rates that Drake inscribed in binary code, on the distance markers that linked to our sun on the map.

Of course Pulsars rate of spin slows down over time and astonishingly, this can be detected as well. So theoretical intelligent aliens could, calculate the difference between these pulsar’s spin rates when they find the map, between the spin rates inscribed on the map, thus intelligent beings could figure out the duration of time since the map was made.

Depending on how altruistic you are, this was either a brilliant move or extremely dangerous given the fact that we have no idea what is out there.

The Golden Records are however far beyond our reach now. Voyager 1 is more than 137 AU’s (1 AU=distance earth is from the sun) from Earth. Voyager 2 is over 113 au’s from Earth and on it’s way for an encounter in 296,000 years’ time with Sirius, the brightest star seen from our home planet


In 1992, Drake authored, “Is Anybody Out There?” which chronicles his work with SETI and his thirty year intensive search among the cosmos.

Despite the book being almost thirty years old now and published before the first exoplanet discovery (1995), it still offers a look into the brilliant and curious mind of a man, not afraid to look up and ask one of the most fascinating questions; Is anybody out there?



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