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Space Station View of the Full Moon

Credit: NASA & ISS

The Drake Equation (sometimes known as: Green Bank equation or the Green Bank Formula)

The Drake Equation is a formula that may calculate the possibility of contactable extra-terrestrial alien species. 

Proposed by Frank Drake in 1961, the Drake Equation is a probability argument that would estimate how many contactable, active and communicable alien species there are in our Milky Way. 

The Drake Equation is, as follows;

N = R* • fp • ne • fl • fi • fc •  L.

In this equation, N =  the number of civilizations in our galaxy with which communication might be possible. 

R* = the average rate of star formation in our galaxy.

fp = the fraction of those stars that have planets

ne = the average number of planets that can potentially support life per star that has planets

fl = the fraction of planets that could support life that actually develop life at some point

fi = the fraction of planets with life that actually go on to develop intelligent life (civilizations)

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

L = the length of time for which such civilizations release detectable signals into space

The Drake Equation acts as a summary of which we can expect to communicate (if at all) with those who are extra-terrestrial.  The last four parameters: fl, fi, fc and L, are not known and are very hard to estimate, with values ranging over many orders of magnitude. 

Therefore it is not a direct measurement of when we will communicate but a roadmap towards creating and estimating the means necessary to communicate with our space buddies. 

Goodbye to M42 for this year.  But I’ll see you again in November.  Meanwhile I can look at this picture I took in January of this year.

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4 hour star trails timelapse at Point Reyes

How the sun abducted dwarf planets from an alien solar system : porkchop_d_clown || ourspaceisbeautiful.tumblr.com

Cassini prepares for final orbital “Grand Finale” at Saturn.

Erik Wernquist, the same filmmaker who created 2014’s “Wanderers” and a stunning New Horizons promotional film in 2015, has created a new video highlighting NASA’s Cassini mission’s final days at Saturn. The Cassini spacecraft will begin its final series of orbits to cap a 13-year groundbreaking science mission known as the Grand Finale. For the first time ever in Cassini’s time at Saturn, the spacecraft will fly in between the planet’s rings and atmosphere. No spacecraft has ever before flown in this region of any of the solar system’s ringed planets. After 23 orbits, Cassini will dive into Saturn’s upper atmosphere September 15 where it will be destroyed. In 2008, mission managers explored a range of End of Mission scenarios that would protect Saturn’s moon’s from Earthly contaminants before ultimately deciding on atmospheric reentry. Cassini began her End of Mission manoeuvres on November 26, 2016, when it began the first of 20 ring-grazing orbits. A close flyby of Titan April 22 will alter the spacecraft’s trajectory to begin the first of 23 orbits in the Grand Finale, which will begin April 26.

Cassini launched from Earth on October 15, 1997, and entered Saturn orbit June 30, 2004. Six months later, on January 14, 2005, the European-built Huygens probe attached to the spacecraft landed on Titan, becoming the first probe to land in the outer solar system. 

Originally scheduled for a four-year mission ending in 2008, Cassini received two mission extensions in 2008 and 2010, with the latter ending in 2017. With the spacecraft’s fuel reserves low, the Cassini team decided to end the mission. P/C: JPL/Erik Wernquist

Our planet seen from Saturn, captured by the Cassini spacecraft

Image credit: NASA / Cassini

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