4
$\begingroup$

Here is a great answer with photos of the shadow of the moon on the Earth's surface (umbra) during a total solar eclipse, taken by real people in space, and links to even more of them. I think there's been about seven in total (see here and here).

But has the Moon's shadow on the Earth (solar eclipse umbra) ever been photographed from beyond Earth orbit? For this question photos by satellites are of course fine!

$\endgroup$
  • 1
    $\begingroup$ We don't send much spacecraft beyond earth orbit, and when we do, they tends not to linger much long in earth vicinity where they could take a picture of a relatively rare event. Besides, they usually have much better things to do during this short time than expand monopropellant to orient their limited telephoto lens towards earth. $\endgroup$ – Antzi Aug 30 '17 at 4:45
  • $\begingroup$ If you mean the LRO picture, since it is on the moon, which is in earth orbit, I thought it would be disqualified by your requirements. (A deep space picture). $\endgroup$ – Antzi Aug 30 '17 at 5:03
  • $\begingroup$ From fr.wikipedia.org/wiki/Inclusion_(mathématiques) and the transitivity rule (See en.wikipedia.org/wiki/Transitive_relation ) , Given Earth orbit E and Moon M; (E⊂M and M⊂LRO) => E⊂LRO $\endgroup$ – Antzi Aug 30 '17 at 5:24
  • $\begingroup$ @Antzi I have just asked How many spacecraft have taken a “Pale Blue Dot” type photo of the Earth from beyond cis-lunar space? and I think you will be surprised at the number of spacecraft that have done so. $\endgroup$ – uhoh Aug 30 '17 at 5:54
11
$\begingroup$

The Earth Polychromatic Imaging Camera (EPIC) on the Deep Space Climate Observatory (DSCOVR) spacecraft has observed both the 2016 and 2017 eclipses and probably every solar eclipse since it's arrived, as EPIC is always looking at the sunlit part of Earth. DSCOVR is at the Sun-Earth L₁ point, roughly 4× farther out than the Moon.

2016 (edited and zoomed in):

DSCOVR eclipse photo
Source: NASA.

2017 (entire disk, straight from image browser): DSCOVER eclipse photo 2017
Source: NASA

You can browse photos for yourself at the EPIC browser, searching for 2017-08-21 and you'll see the so-called “Great American Eclipse” soon enough.

NASA also produced an animation at of the 2016 eclipse at:

https://earthobservatory.nasa.gov/NaturalHazards/view.php?id=87675

Sun-Earth L₁ is 1.5 million km from Earth, which is farther than the Moon, which has a semi-major axis of 384,000 km.


Although it didn't seem to happen during the eclipse, during the solar eclipse or indeed any new Moon, the Moon can't be very far from the field of view of EPIC. Indeed, sometimes the Moon "photo bombs":

not an eclipse


Not quite as far away is the Lunar Reconnaissance Orbiter (LRO), which took the following photo during the 2017 total eclipse. Note that during a solar eclipse (and any new moon) the entire disk of the Earth is sunlit as seen from the moon:

LRO eclipse photo

$\endgroup$
  • $\begingroup$ Lissajous orbits are Heliocentric orbits that are a bit wiggly because they are modified by the Earth a bit, but they are not in Earth orbit. Very nice! $\endgroup$ – uhoh Aug 30 '17 at 9:34
  • $\begingroup$ Did you want to include the other satellite's recent photos in your answer? Eventually I'll post it as another answer if nobody else does. $\endgroup$ – uhoh Aug 31 '17 at 0:16
  • 1
    $\begingroup$ @uhoh I am not sure what other satellite you mean. Do you mean LRO? $\endgroup$ – gerrit Aug 31 '17 at 10:21
  • $\begingroup$ ya, it's in orbit around the Moon. If the Earth disappeared tomorrow it would stay in orbit around the moon. So I think it's safe to say that it's not in orbit around the Earth. It's not LRO's fault that the Moon just happens to be in orbit around the Sun. For example, when something is in LEO we don't say that it is in orbit around the Sun, even though we know the Earth is in orbit around the Sun. In an inertial frame, DSCOVER circles around the Earth once a year, but we don't call that an Earth orbit either. So LRO counts for this question at least. $\endgroup$ – uhoh Aug 31 '17 at 10:45
  • $\begingroup$ @uhoh Added that one and another photo where the moon photobombs EPIC. Next time we have an eclipse at the same latitude of the sub-solar-point that's bound to happen simultaneously! $\endgroup$ – gerrit Aug 31 '17 at 10:51
2
$\begingroup$

You can now see a smooth animation of the last 8/21 eclipse using the Blueturn app:

http://app.blueturn.earth/?date=2017-08-21_15-35-54

More generally, this app interpolates EPIC images received from DSCOVR using relat-time 3D projection techniques. In such this is the first and only interactive video of the Whole Earth, with 2+ year of data. Very recommended!

$\endgroup$
  • $\begingroup$ It's a web app, nothing gets installed on your machine $\endgroup$ – maksimov Nov 19 '17 at 11:18
  • 1
    $\begingroup$ @uhoh Yes indeed I answered several questions related to DSCOVR with a link to my app, as I thought it is relevant, and I want to make it known by the space community. It is a free app, with no ads. It exists as a web app or as a mobile app (Android or iOS) if you open it from your phone or tablet. Enjoy, and sorry if it may have felt obnoxious. $\endgroup$ – Michael Boccara Nov 20 '17 at 10:56
  • $\begingroup$ @Mic thanks for the reply - OK that sound great. Looking forward to it! $\endgroup$ – uhoh Nov 20 '17 at 11:08

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.