DSCOVR (EPIC) · 16 July 2015, 21:37 UTC
The Moon crossing the Earth
From a million miles out, near the Sun-Earth L1 point, NASA's EPIC camera watched the Moon cross in front of the Earth, its far side fully lit: a face no one on Earth ever sees.
Slide between them
The original laid over the live view at the same scale, as the viewer does when you press Both or Original. Drag across the picture, or use the arrow keys.
Where it was taken from
DSCOVR (EPIC) was 1.5 million km from the Earth at 21:37 UTC on 16 July 2015.
The live view puts the viewer's camera right there. The clock goes to that moment, everything switches to true scale, and the camera sits where the spacecraft was, its position from JPL Horizons, NASA's ephemeris service, for that moment [4]. The lens matches the published picture, 0.62° from top to bottom, and the camera is turned to the picture's own orientation, so the original lies over the view at the same scale.
Where the two differ
Everything in the live view comes from the viewer's own maps and its own light, drawn at one instant. The geometry comes from the spacecraft's position, the lens and the picture's orientation, so where everything was, how big it looked and which way it was lit should all line up with the original.
The facts
- NASA's EPIC camera on NOAA's DSCOVR satellite took these images on 16 July 2015, from about a million miles away. [1]
- They show the far side of the Moon fully lit, a face never seen from Earth. [1]
- Each colour picture combines three exposures about 30 seconds apart. The Moon moved between the first (red) and the last (green), which leaves a thin green fringe on its right edge. [1]
- Mare Moscoviense is at the upper left of the Moon and Tsiolkovskiy crater at the lower left. [1]
- DSCOVR sits off the Sun-Earth line, so the transit casts no shadow on the Earth. [2]
- EPIC is a 30 cm telescope with a 2048 by 2048 pixel camera and a 0.62 degree field of view. [3]
Open it live
In the viewer the clock runs on from the moment at real pace, so you can watch the scene move the way it did after the shutter closed. Press Both or Original to lay the original over it, or drag to look around from where DSCOVR was.
Open it live in 3D → All eight as a Mac screensaver
The other seven
The Blue Marble
Earthrise
The Earth and Moon, together
Pale Blue Dot
The Day the Earth Smiled
In Saturn's Shadow
Pluto in true colour
All the famous photos, and how the views are made
Sources
- NASA: From a Million Miles Away Nasa Camera Shows Moon Crossing Face of Earth
- NASA EPIC: Lunar transit 2015 gallery
- NASA EPIC: the camera
- NASA JPL: Horizons ephemeris system
Original picture: NASA/NOAA (NASA EPIC Team), from NASA: From a Million Miles Away Nasa Camera Shows Moon Crossing Face of Earth. The EPIC team allows its pictures to be reused with credit. About EPIC. The live view is ours, rendered by the Our Solar System viewer.