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NPR's March 10, 2023 "Newly found asteroid has a 'very small chance' of hitting Earth, NASA says" https://www.npr.org/2023/03/10/1162659328/asteroid-2023-dw-nasa-earth-impact File - SNL MrBill Doll.jpg from https://commons.wikimedia.org/wiki/File:SNL_MrBill_Doll.jpg

(Image sources linked below)

NPR's March 10, 2023 Newly found asteroid has a 'very small chance' of hitting Earth, NASA says includes an image of what looks like a computer reconstructed 3D surface of an asteroid, perhaps from delay-doppler radar imaging or optical images (photographs) taken at many solar phase angles.

Similar but smaller rendering at a different angle can be seen in ABC News' January 19, 2023 Huge asteroid safely passes close to Earth

Due to the miracle of Pareidolia I'm seeing two big eyes with pupils (could also be seen as a big pair of round glasses), a triangular nose, and a big round circular mouth reminiscent of Mr. Bill's "Oh no!"

Question: How did asteroid (7482) 1994 PC1 get its "face"? How was the surface topography (assuming this is really from data) reconstructed and rendered? What data was used, and primarily from what instrument(s)?

NPR's March 10, 2023 "Newly found asteroid has a 'very small chance' of hitting Earth, NASA says" https://www.npr.org/2023/03/10/1162659328/asteroid-2023-dw-nasa-earth-impact

Asteroid 2023 DW will make a close approach to Earth on Feb. 14, 2046. NASA and other agencies are closely monitoring the asteroid to learn more about its projected path. NASA


Image sources:

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These are images taken from Nasa's Eyes on Asteroids site. It lets you see the orbit and get information about the asteroid in a nice interactive way. For asteroids with a known shape and surface texture, it will use that information. (Try searching for Bennu) But most asteroids have no known surface information, and the system uses a standard texture for these asteroids. The texture is "artistic" rather than being based on any particular data.

In the case of 2023 DW, there is no shape nor surface data, so the Eyes on asteroids site provides a standard "potato" with "eyes". If you look at other random asteroids, such as 2023 AA you'll see they are exactly the same. Trying it out a few times suggests that there are a few different "shapes" and "textures" and they are chosen randomly.

Nasa could be blamed for not making it clear which asteroids have "real" and which have "imagined" details. It's not surprising that these picture find their way to the media, where they are likewise presented as "a picture from NASA of the asteroid".

The upshot of this is that there is no data. Even the shape of this asteroid is unknown, and the surface details were drawn in by analogy with other asteroids.

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    $\begingroup$ I'm curious; you state without any support that "In the case of 2023 DW, there is no shape nor surface data" What makes you say this? How do you know? I think the hallmark of a good Stack Exchange answer is that facts and assertions are supported with links and references, and this assertion is absolutely key to your answer. You must have looked that up somewhere, why withhold the source? $\endgroup$
    – uhoh
    Mar 12, 2023 at 23:28
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    $\begingroup$ I thought this same thing... when I saw the article I went searching for other images, and they all looked suspiciously like not actual photographs $\endgroup$
    – Michael
    Mar 13, 2023 at 3:10
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    $\begingroup$ NASA absolutely should be blamed for blurring the line between imagined but photorealistic images and actual astronomy images. The constant confusion caused by this practice (see e.g. all the beautiful "images" of exoplanets) is going to hurt the scientific community (and NASA). I am begging them to stop this practice and be more responsible. $\endgroup$ Mar 13, 2023 at 19:12
  • $\begingroup$ @user71659 Still a lot better than getting another generation of flat earthers or space deniers, whose default approach to anything is "NASA lies". Being realistic about the limitations also lets people appreciate better whenever these limitations are being expanded. $\endgroup$
    – zovits
    Mar 14, 2023 at 10:40
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The face situation is getting curiouser and curiouser!

At first, when I went to the actual page in NASA Eyes for the asteroid https://eyes.nasa.gov/apps/asteroids/#/asteroids/7482_1994_pc1 I could not find the face that @JamesK's answer says is there.

I looked everywhere and couldn't find the three nearly equal size craters touching each other with a little triangular "nose" in the center, and two much smaller craters in the center for pupils:

screenshot towards the Sun NOT showing the face, at about 08:20 (UTC+8 local time) on March 13, 2023 from https://eyes.nasa.gov/apps/asteroids/#/asteroids/7482_1994_pc1

But when I opened the page again in a new tab, I found a completely different asteroid! In this tab, looking in the same direction at the same time (live, about 08:20 (UTC+8 local time) on March 13, 2023, there it is!

The face seems to come and go.

Oh noooooooo!....

screenshot towards the Sun showing the face, at about 08:20 (UTC+8 local time) on March 13, 2023 from https://eyes.nasa.gov/apps/asteroids/#/asteroids/7482_1994_pc1

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  • $\begingroup$ One supposes the ateroid rorates. Also your first image is flipped with respect to OP's second image -- compare the orientations between the overlapped small and large crater in both images. Once you understand this, you'll realize the "face" would be on the other side of the asteroid in your first image. $\endgroup$
    – Spencer
    Mar 13, 2023 at 0:42
  • $\begingroup$ @Spencer NO, the images are only 1 minute apart (in sim. time), and I've shown the face opposite the Sun in both cases; the Sun is at the center of both images, one can see Mercury's purple orbit behind the asteroid in both images. And in both cases I have rotated the view exhaustively to see the asteroid from all angles. After spending some time, I'm pretty confident that the NASA site is putting up at least two alternate renderings. I invite anyone else to carefully redo the experiment. Open the page in several different tabs, or several different times, and try to see the face each time $\endgroup$
    – uhoh
    Mar 13, 2023 at 1:05
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    $\begingroup$ I mentioned this in my answer. There are a few different shapes and they are chosen randomly. $\endgroup$
    – James K
    Mar 13, 2023 at 6:16
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    $\begingroup$ At some point "a guy that's been doing this for a long time and sharing his experience" is a pretty good source in and of itself. Often better than the "support" we've been taught to crave so unconditionally. $\endgroup$ Mar 13, 2023 at 16:04
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    $\begingroup$ @MadPhysicist future readers and those here via search results (rather than being frequent user) have no way to judge such things, and the internet is full of folks who project the aura of "doing this for a long time and sharing his experience" whether they do or not. Stack Exchange is an oasis in the cacophonic internet, supporting sources for facts and assertions, along with excellent moderation, is what distinguishes it from that. It ain't broke, doesn't need fixing. Quora's a good place for answers from folks who project the aura of "doing this for a long time and sharing their experience" $\endgroup$
    – uhoh
    Mar 13, 2023 at 21:40

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