How Bright is Daytime on Pluto?
We all know that Pluto is very far from the Sun, on average about 40 times as far away from it as Earth is, and as such it is very cold and dark. But just how dark is it on Pluto? If you were an astronaut walking around on Pluto would the Sun really just look like another bright point in an already star-filled sky, or would you actually be able to see the Plutonian landscape around you during the day (like in the illustration above by Ron Miller?)
Actually it’s brighter than you might think, even three and a half billion miles from the Sun. And with the New Horizons spacecraft closing in on the first-ever pass by Pluto in July, NASA has a way for you to get an idea of the type of lighting you would experience on the surface of Pluto… and a way for you to share it with the world.
With NASA’s new PlutoTime page you can find out when in your location on Earth it’s as bright outside as it is mid-day on Pluto. Just plug in your coordinates or address and it will tell you the precise time of day when the natural ambient illumination is most similar. (Not considering artificial lighting, cloud cover, or other interfering atmospheric phenomena of course.)
Then you can take a picture from your location and share it on Facebook, Twitter, Instagram, Flickr, or YouTube with the hashtag #PlutoTime, and NASA will compile all of the images and create a montage using those along with some of New Horizons’ best views of Pluto and its moons, similar to what was done with Cassini’s picture of the Earth from Saturn in 2013.
And, if you’d like a page to fill in your location and name, feel free to download and print the image below (courtesy of your favorite space news site!)
The time is usually just after sunset in your location – given a clear day it’s not all that dark, is it? You can easily see things around you without additional lighting and probably even read a book.
In fact Phil Plait (widely known as the Bad Astronomer) did the math on this a few years back when he was writing for Discover Magazine’s online site. He determined that, based on its average distance from the Sun* and how illumination mathematically decreases with distance, the Sun from Pluto would look about 250 times brighter than a full Moon does on Earth! (Read that article here.)
Of course it’s still darn cold on Pluto, on average –375ºF (–223ºC)… don’t let that bright Sun fool you. 😉
New Horizons has been traveling through space for over nine years, and now it is in the last few steps of its final leg to reach the Pluto system – in fact it’s now sending back the most detailed images ever captured of Pluto! Everything from now on will be a superlative with the mission – click here to see what principal investigator Dr. Alan Stern had to say about it all during an interview I held with him in March.
Follow the latest news from the New Horizons mission here, and find out where the spacecraft (and Pluto) is here.
*Because Pluto has a highly elliptical (egg-shaped) orbit there is a big difference between its closest distance to the Sun and its farthest distance from the Sun. The closest Pluto gets to the Sun is 2,756,902,000 miles (4,436,820,000 km) which is actually closer than Neptune. The farthest Pluto gets from the Sun is 4,583,190,000 miles or (7,375,930,000 km). Source