Pale Blue Dot

In The Hitchhiker’s Guide to the Galaxy, author Douglas Adams concocts the “Total Perspective Vortex,” a device which shows a person exactly where they are in relation to the entire universe.  The Total Perspective Vortex is, to say the least, a dangerous device — it gives the user a sense of perspective he or she simply cannot handle, causing the viewer’s brain to self-destruct in a fit of relative unimportance.  (Want to read the passage? Click here to go to the book’s Amazon page, click the book cover to “look inside,” and in the pop up box, type “Trin Tragula.”  When the “look inside” window pops up, click the blue link on its left.)

While the Total Perspective Vortex is fiction, the image above is not.  (One can see a slightly larger version of the image here.)  In the light brown band on the right of the image, near the middle but toward the bottom half, is a pale blue dot.  That dot is Earth, as seen from 3.7 billion miles away.

On September 5, 1977, the United States launched Voyager 1, a deep space probe designed to study the outer Solar System.  Still in use today, Voyager 1 is the furthest man-made object from the Earth.  It is controlled via radio signals and sends back images in the same manner, including the one seen here, called “Pale Blue Dot.”  Taken in 1990 on the request of astrophysicist Carl Sagan, the image is one of five dozen pictures of our Solar System, collectively known as the “Family Portrait.”

Per NASA, the brown bar is a scattered ray of light on the camera’s lens, due to Voyager 1’s proximity to the sun.  And for perspective’s sake?  The pale blue dot is exceptionally tiny — roughly a tenth of a pixel.

Bonus fact:  Two deep space probes — Pioneer 10 and Pioneer 11 — are not where they are supposed to be, having decelerated more than anticipated — and we don’t know why.

From the Archives: Earth 2.0. There’s another Earth-like planet out there.

Related reading: Sagan authored a book, centered on the picture: “Pale Blue Dot: A Vision of the Human Future in Space.”  It was a New York Times bestseller, and has 58 four or five star reviews on Amazon, out of 66 total.