Help Shape the Future of Space Exploration

Join The Planetary Society Now  arrow.png

Join our eNewsletter for updates & action alerts

    Please leave this field empty

Headshot of Emily Lakdawalla

Diamond Ring Earthrise

Posted by Emily Lakdawalla

18-02-2009 12:46 CST


EDIT: Thanks to Jay Pasachoff for correcting me -- it's the Sun's photosphere, not corona, that makes the brilliant diamond on the ring.

And thanks to Daniel Fischer for pointing out this video sequence of the Earthrise, of which the image I show below is a still. Cool!

JAXA and NHK just released this lovely shot of an Earthrise taken by Kaguya during a penumbral lunar eclipse, when Earth blotted out almost all the light from the Sun except for one tiny edge of the Sun's disk. The sunlight peeking over the edge of the disk at about 4:00 makes the brilliant "gem" on the "diamond ring" -- the ring is, I believe, Earth's atmosphere, scattering sunlight forward to the camera.

Diamond Ring Sunrise


Diamond Ring Sunrise
On February 10, 2009, Kaguya witnessed a simultaneous Earth- and Sunrise, with the Earth mostly blocking the spacecraft's view of the Sun. The result is this lovely "diamond ring" image, where Earth's bulk is slightly offset from the Sun's disk, allowing a tiny sliver of the Sun's photosphere to peek over the lower-right edge of Earth's disk, shining as a brilliant point of light.
Here's a slide from a Japanese-language presentation (I'm not sure what the occasion of the presentation was), which shows how the edge of the lunar disk is blocking part of the view of the diamond ring, and also, at lower right, the geometry of the observation.
Geometry of the Kaguya 'Diamond Ring' photo


Geometry of the Kaguya 'Diamond Ring' photo
This presentation slide explains (in Japanese) the geometry of the "Diamond Ring" Earthrise photo captured by Kaguya on February 10, 2009.
FYI, the same presentation includes a map showing the location of the impact of the Okina satellite: 200.967E, 28.213N, or a little north of the equator near the center of the lunar farside. It also contains the news that Kaguya's own lunar impact is expected to take place in June of this year. Thanks to "Subaru" on for the tip!

See other posts from February 2009


Or read more blog entries about:


Leave a Comment:

You must be logged in to submit a comment. Log in now.
Facebook Twitter Email RSS AddThis

Blog Search


Advocate for Space!

Fifteen years ago, Society members and passionate space advocates like you helped save the Pluto mission. Now we can do the same for missions to Europa and Mars.

Join over 26,400 people who have completed their petition and consider a donation to support advocacy efforts.

Sign Our Petition

Featured Images

Chang'e 5 T1 image of a potential landing site for Chang'e 5
Lunar Polar Hydrogen Mapper (LunaH-Map)
Soyuz TMA-18M liftoff
Soyuz TMA-18M launch crew
More Images

Featured Video

Bill Nye & Neil DeGrasse Tyson on a Roof

Watch Now

Selfies to Space!

Take flight with a selfie on LightSail™ in 2016!

Send a Selfie Now

Join the New Millennium Committee

Let’s invent the future together!

Become a Member

Connect With Us

Facebook! Twitter! Google+ and more…
Continue the conversation with our online community!