So observing the energy balance of the sunlit side of the planet turns out to be possible because of a peculiar consequence of orbital dynamics. And it turns out that, although a clever idea for "an expensive screen-saver", and arguably worth it for that purpose alone, such a satellite, properly instrumented, could offer important constraints on the earth's energy budget.
In short, if the consensus understanding of climate change really were badly wrong, this instrument would almost surely provide enough information to prove it.
The instrumentation and platform was proposed in 1998 in conversations initiated by then Vice-President Gore and quickly constructed; it was ready for launch in 1999. But Republican pressure in the 1999 budget negotiations mothballed the project, disparagingly called "Gore-Sat" by its opponents. (In some circles, and mention of Mr. Gore is considered disparaging. He's sort of like Mike Mann in that way, a serious, moderate, thoughtful and highly competent person who has somehow been painted as a demon. Witness modern discourse at its best.)
And in mothballs it sat. Because Al Gore. Because conspiracy. Surely not because the data would utterly fail to upend the existing consensus and would help refine it.
Until this year, when it was launched. Until today, when its first image of the whole earth was released, to much calloo-ing and callay-ing.
Here's Neil de Grasse Tyson's celebration of the image, which was released as a memo by the White House.
Here's astronaut Scott Kelly.
Here's Robinson Meyer at The Atlantic.
All the happy talk today seems to be trying to bury the very interesting back story of Republicans practically sabotaging the launch by delaying it for an absurd amount of time. Wikipedia has links on that
Going back to what I myself said a few years back, there is likely to be a deeper and more interesting story here than has been told to date:
Would it have been more sensible to redesign the platform rather than launch an almost 2 decade old gizmo? Is this the best instrumentation for the mission to launch today? I don't propose to have answers for those questions; I would not be surprised if the contemporary purpose of the launch is almost as political as the purposes of the absurd delay.
These are also things worth talking about.
That all admitted, I would defend the screen-saver aspect of it. Actual photos of the whole earth available on a daily basis are worth the few cents per capita that we actually spent on this thing. Providing collectively funded information of collective utility is a legitimate function of government.
Science has never been the sole purpose of NASA, or we wouldn't have sent astronauts to the moon.
Apparently taking pictures of Pluto is less controversial than taking pictures of the Earth, though.
Welp, Pluto is cool too. Perhaps a bit too cool, but that's another tale, nicht wahr?