NPR's news item and audio podcast New Chinese Space Plane Landed At Mysterious Air Base, Evidence Suggests draws heavily from information and quotes from noted astronomer with the Harvard-Smithsonian Center for Astrophysics Jonathan McDowell who frequently tweets science and object tracking and it seems has also answered a question here.

The article notes:

They didn't give a launch time. They didn't give any more details," McDowell says. The U.S. military picked up the new spacecraft on its tracking network, and McDowell and others quickly plotted its orbit. When they did so, they found that China's new craft passed over a secretive military facility: an area called Lop Nur where China once tested its nuclear weapons.

Question: Does McDowell have some special security clearance in order to see what "The U.S. military picked up the new spacecraft on its tracking network" or does the US military put this information out there in a semi-public way that doesn't require a security clearance in order to see it. Or did McDowell use sources other than military, cf. How are military satellites with (apparently) classified TLEs still showing up on sat map websites? If the source is public, what is it?

I can haz U.S. Military Tracking Network Data? meme

I don't think my question is inappropriate, because it is about a public figure's public statements in one of their fields of specialty. McDowell is also referenced in many other posts here in similar capacity, just for example:

  • $\begingroup$ yes I know the "z" belongs in "cheezeburger" but the letter is so endearing I move it to "haz" in order to preserve its heritage. $\endgroup$
    – uhoh
    Sep 12, 2020 at 6:33

2 Answers 2


I'm assuming the reference is to http://space-track.org, where the US government publishes its information on satellite locations to the world. I just checked, the plane is on the site. So far as I know he doesn't actively have a security clearance, but he does have access to some archival data that isn't easily accessible, and I believe he has at least some conversations with them to get some clarification on procedures and the likes.

Proof this is how he gets current TLE access:


  • $\begingroup$ Thanks for the speedy, authoritative and informative answer! $\endgroup$
    – uhoh
    Sep 12, 2020 at 6:47
  • 1
    $\begingroup$ Belatedly: I confirm this is correct. I have no security clearance and I don't even have the "special" operator access to space-track.org, just a regular account. The story cited by the OP involved me downloading data from space-track and doing analysis using my own code. Source: I am Jonathan. $\endgroup$ Apr 10, 2023 at 23:04
  • $\begingroup$ I'm constantly amazed by what you have pulled from this data. I'm surprised you don't even have archival information beyond what is public. Wow! $\endgroup$
    – PearsonArtPhoto
    Apr 11, 2023 at 13:46

Space Track publishes TLE data on non-classified objects.

Data for classified satellites is usually published by several satellite observers, who consider this a hobby.

Most recent occurrence would probably be NROL-44, which is set to launch in the coming days.

It should be noted, that due to the number of objects in space, several states continuously track these to avoid collisions.

It should also be noted, that start place, time and intended orbit need to be published by all states in advance. This is regulated by international treaty.


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