Recently I've been reading about a bit of Chinese space stuff and I found the accusation that the US hid orbital data for the asteroid 4179 Toutatis after China announced that they planned to send Chang'e 2 there, in 2012. Now while this the US isn't exactly against slights and this was very soon after the Wolf amendment, this still feels pretty extreme and I haven't found any mention of it in Western sources. (though that's probably not a big surprise)

Can this accusation be verified?


Weiren said that China's lunar exploration project started in 2003. Although the number of launches is not many, the results have been fruitful. After Chang'e-2 completes its lunar exploration, it will detect the L2 point of Lagrange and make a leap detection of the asteroid Tutatis. He recalled that the orbits of many small celestial bodies in the world are only available in the United States, and they were originally open to the world. When China announced that it would detect Tutatis, the United States immediately shut down all relevant orbital data. (google translated quote)

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  • $\begingroup$ I would not be surprised if what happens is that they were poking around in someone's computer at NASA or some university surreptitiously and somebody discovered it and simply added some network security. It makes no sense for public data to suddenly be hidden, there would be copies everywhere; the backdoor access being "pulled down" is a likely explanation if anything happened at all which probably didn't. $\endgroup$
    – uhoh
    Commented Oct 15, 2020 at 13:18

1 Answer 1


Just checked from the JPL Horizons website. It seems that it is in fact still there. I also looked at the JPL Small-Body Database. Looking up Toutatis, it says it was last updated in 2003. It seems very unlikely that it was specifically deleted because China wanted to send a spacecraft there.

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    $\begingroup$ That last update in 2003 on the JPL Small Body DB is the discovery circumstances. Looking further up, you can see that it was last observed on 2020-08-17 and JPL computed a new orbit fit the next dat (solution date 2020-Aug-18 06:07:19) after the data would have been reported to the MPC and then retrieved from there by JPL. All totally normal updated orbit fitting to new data. Orbital elements and all the observations are available from the Minor Planet Center DB $\endgroup$ Commented Oct 15, 2020 at 15:55

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