NOAA’s aging fleet of sun-observation satellites

Chronological Encyclopedia of Discoveries in Space cover

After being in print for twenty years, the Chronological Encyclopedia of Discoveries in Space, covering everything that was learned on every single space mission in the 20th century, has finally gone out of print.

I presently have my last four hardback copies available for sale. The book sold new for about $90. To get your own autographed copy of this now rare collector's item, please send a $120 check (which includes shipping) payable to Robert Zimmerman to

Behind The Black, c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652

"Useful to space buffs and generalists, comprehensive but readable, Bob Zimmerman's Encyclopedia belongs front and center on everyone's bookshelf." -- Mike Collins, Apollo 11 astronaut


"The Chronological Encylopedia of Discoveries in Space is no passionless compendium of information. Robert Zimmerman's fact-filled reports, which cover virtually every spacecraft or probe to have ventured into the heavens, relate the scientific and technical adventure of space exploration enthusiastically and with authority." -- American Scientist

In testimony during a Senate hearing on February 12, the head of NOAA’s space weather division admitted that the agency’s ability to monitor the Sun is threatened by its aging fleet of solar satellites, combined with the agency’s slow progress on a large single replacement satellite, presently scheduled for launch in 2024.

NOAA currently uses the Deep Space Climate Observatory (DSCOVR) and NASA’s Advanced Composition Explorer (ACE) spacecraft to collect solar wind data, and uses the ESA/NASA Solar and Heliospheric Observatory (SOHO) spacecraft to observe the solar corona, using those data to forecast solar storms that can affect satellites and terrestrial infrastructure such as power grids.

However, SOHO, launched in December 1995, is well past its design life. In addition, DSCOVR has been offline since June 2019 because of technical problems, forcing NOAA to depend solely on ACE, which launched in 1997. [emphasis mine]

NOAA has been trying, and failing, to build a replacement for ACE for more than a decade. Worse, the agency’s inability to deal with these issues was further revealed by this quote:

Congress has pushed to speed up work on that [replacement] mission, despite NOAA’s assurances about the availability of data from other spacecraft. NOAA sought about $25 million for the mission in its fiscal year 2020 budget request, but Congress appropriated $64 million. NOAA has yet to release its fiscal year 2021 budget request, more than a week after the White House published the overall federal government budget proposal.

Something has been wrong in the management at NOAA now for at least a decade. They can’t seem to get new satellites built, and when they try they can’t seem to do it on schedule and for a reasonable cost. Their weather satellite program has been rife with problems, including cost overruns, schedule delays, and failing satellites.

But why should we be surprised? This kind of mismanagement at the federal government has been par for the course for the past half century.



  • Phill O

    One would hope that the new satellites would not just be replacements but offer new equipment to further our understanding on main sequence stars: particularly our very own one.

  • David

    Phill, that’s exactly the problem. Here we have a basic observational need, but no, we can’t possibly launch several simple observational satellites, we have to have all the latest gee-wiz bleeding-edge instruments on it. And then it takes forever to make those instruments, and they cost a ton of money, so we only launch one every decade or so, and it’s years late and massively over budget when it finally launches. If we were launching a cheap satellite every say 5 years, with small incremental improvements each time, we’d be in a much better spot.

  • commodude

    F-35 and LCS redux.

    David is exactly correct, with the sole exception that those gee whiz gadgets get upgraded and replaced during the design and build cycle, leading to changes after the chassis and other large pieces are built, leading to changes, and creates a vicious circle of redesign and upgrade until someone says ENOUGH!

  • Col Beausaber

    While I won’t comment on the F-35 as I think the jury is still out (and I remember the C-5, F-111, UH-60, AH-64, M1 Tank, M2 Infantry Fighting Vehicle all being condemned as disasters with the crowd that came to scoff remaining to cheer), the history of US small combatants since WW2 truly is a story of one failure after another. Worse still is the Zumwalt class destroyers, $4B plus ships which have NO ARMAMENT!

  • Phill O

    You folk are talking the basics of design and the logistics of launch, to which I can agree wholeheartedly.

    That being said, I was thinking that if more research went to investigating our sun, particularly in relation to climate, we might know a tremendous more: on subjects we thought we new it all or did not know we did not know.

  • pzatchok

    How much would NASA pay a private satellite/probe owner for the data they collect?
    How much would other nations pay for the same data?
    How about a consortium of universities?

    I wonder if someone could launch a few and see if someone buys in?

  • commodude

    With the current state of the launch industry, NASA would likely be better served by small, simple single purpose instruments rather than trying to cram multiple instruments into one package. Once you start building things intended to do all things well, you compromise on results, and the end product either winds up costing many times over budget and late, or winds up doing many things mediocre and nothing truly well.

Leave a Reply

Your email address will not be published. Required fields are marked *