The impact will be at the large green 'X', on the far side of the moon, in
the large, old crater
Hertzsprung. For scale, Hertzsprung is about 520 km
(315 miles) across.
Created 2022 Jan 21 16:43:51 UT using Find_Orb
Click here for an explanation of pseudo-MPECs
(2022 Mar 4) Added a comment about confirmation of impact
UPDATE : comments on Chinese statement the object isn't actually the 5-T1 upper stage
First... a very big thank you to the observers. This object was annoyingly close to the sun. Still, they got excellent data on this object. (I should note that I'm much more of a "mathematical" astronomer than an "observing at the telescope" one. I'm quite grateful for the data that gets sent to me.)
The actual observational data was provided by the observers. Everything else on this page was written/computed by me (Bill Gray) and can be reproduced freely.
This impact has gotten considerable attention outside the "usual" astronomical community, and I've tried to add some answers to questions. My apologies if this confuses more than it helps!
Where/when will this hit the moon?
My current estimate, based on all the astrometry we got during January and February (i.e., all the data we'll ever have), puts the impact at 2022 March 4 12:25:23, at latitude +5.36, longitude 234.93. Theoretically, this is good to a few seconds and a few kilometers, but reality is less certain; see the section below.
The impact will be at the large green 'X', on the far side of the moon, in
the large, old crater
Hertzsprung. For scale, Hertzsprung is about 520 km
(315 miles) across.
Note that this is the far side (the side we don't get to see from Earth), not the dark side (the one where the sun isn't shining, also known as the "night side"). When the impact happens, it'll actually be not far from "noon" local time there, with the sun shining down almost from directly above.
The longitude, by the way, is East. The IAU (International Astronomical Union) has made a dog's breakfast out of cartographic systems on other planets; I had to go through some contortions to confirm that longitude 243 is on the side toward Mare Orientale, not the side toward Mare Crisium. "Mare Orientale" was named that back when "east" meant that side of the moon. With the new, official, IAU system, it's on the west side.
Also, my apologies; an earlier version of this page had the impact 20 seconds earlier and a few kilometers away. Turns out I'd had my software set to consider an "impact" as occurring at an altitude of 50 kilometers, which is a good thing for an Earth impactor (they burn up high in the atmosphere) but makes less sense for the moon.
Where will it be between now and then?
You may find that this animation showing the motion of the object during 2022 gives you a better idea of what's going on. This shows the path as seen from the "side" of the earth-moon system and a little above it; alternatively, this animation showing the same motion but from directly above the earth-moon system will give you a different angle (literally) on where the DSCOVR stage will be between now and 2022 March 4.
In both animations, the moon is on the white trail that (mostly) repeats in a nice, regular ellipse (there are some changes because the sun is pulling on it gently.) The DSCOVR stage is the green object leaving green trails; its path sometimes changes quite a bit, because it gets close enough to the moon to perturb it.
Both animations were made by Tony Dunn using his excellent Orbit Simulator software.
Below, you can see the path of the object between January 1 and the impact on March 4. The green circle shows the orbit of the moon; the earth is the red circle at center, and the black track shows where the DSCOVR stage is going.
"Most" objects will orbit in ellipses. This one sort of orbits the earth in an elongated ellipse, but the effects of the moon perturb it so that there have been gradual (and sometimes sudden) changes ever since it was launched in 2015. Here's the play-by-play on the above :
After a close-ish flyby on January 1, the object started climbing back to apogee. On the way, it passed about 9600 km from the moon on January 5, at 12:20 UTC; that's the "kink" you can see at that point.
It kept going up to apogee, then returned to where we could get more observations on it between January 15 and 21. After that, it swung around the earth and very quickly was too close in the sky to the sun for anybody to observe. That's where we stand now.
On February 7 and 8, it will come back around for another close flyby over Earth's night side. I expect it will get some more observations then, which will let me compute an improved orbit and say where and when it'll hit with greater confidence and accuracy.
After that, it'll again be too close to the sun to observe from Earth. It will go out in a considerably higher loop, well past the moon, then come in to hit the far side of the moon on March 4.
How confident are we it'll hit where/when predicted?
If this were a rock, I'd be 100% certain. (And I am 100% certain it will hit 'close to' the above point at that time.) But space junk can be a little tricky. I have a fairly complete mathematical model of what the earth, moon, sun, and planets are doing and how their gravity is affecting the object. At this level of precision, even the fact that the earth isn't perfectly round (it bulges out very slightly at the equator) matters; if you ignore that effect, your impact point on the moon is wrong by about 170 kilometers!
I also have a rough idea of how much sunlight is pushing outward on the object, gently pushing it away from the sun. This usually enables me to make predictions with a good bit of confidence.
However, the actual effects of that sunlight are hard to predict perfectly. It doesn't just push outward; some of it bounces "sideways". The object is a long cylinder, spinning slowly; you can see the light from it vary as it tumbles, and you can plot a light curve for it indicating that it rotates about once every 180.7 seconds. (Or possibly every 90.4 seconds. There's often some ambiguity in measuring rotation periods.) When the object spends a good bit of time with its ends pointed toward the sun, it catches less sunlight and isn't pushed away from the sun as much.
You can also see tumbling going on in this video . It's a little "scrambled" because the exposures are a good fraction of the rotation period, but you get the general idea of what's going on.
These unpredictable effects are very small. But they will accumulate between now and 2022 March 4, and we'd really like to determine the impact location as precisely as possible, so that the the Lunar Reconnaissance Orbiter (LRO) and Chandrayaan-2 folks can find the crater (and, if we're lucky, maybe image the impact). At this level of precision, the tiny departures from idealized physics, with its frictionless spherical cows, matter.
At a guess, the above prediction may be wrong by a few kilometers and second from the predicted time. We'll need (and I am confident will get) more observations in early February to refine the prediction; that will bring the uncertainty down greatly.
What was the timeline on figuring this out?
DSCOVR (and this rocket stage with it) was launched on 2015 February 11. About a month later, one of the asteroid surveys found this object and posted it to the NEOCP (Near-Earth Object Confirmation Page). This is where astronomers post data about objects they've found that might be near-earth asteroids or comets; the idea is that others can then try to observe them as well and say "I found it, too, at the following location" or "Hmmm, can't find that one." The discoverers, thinking they had a rock, gave it the temporary name WE0913A.
In this case, a small observatory in California got more data, followed by enough data over subsequent days that I could show that WE0913A had made a close flyby of the moon on 2015 February 13. Deep-space missions sometimes fly past the moon to re-direct them, adding a bit of speed or changing the plane of the orbit. There hadn't been any other launches for months, so I figured this was either DSCOVR or DSCOVR's second stage.
Shortly after that, I learned that DSCOVR was already between the earth and sun, which meant I could cross it off the list; the object was presumably the DSCOVR second stage. (Except it's actually the Chang'e 5-T1 upper stage.)
Over subsequent months and years, more data came in, and I was able to determine a few more close lunar passes and say something about how sunlight was pushing it around. I kept updating the orbital data for it, and provided files and software so that asteroid observers could check to see if their "new" find was actually a bit of junk. And a few bits of data kept coming in every few weeks or months.
On 2022 January 5, the object passed close to the moon. Eight days later, it was imaged again, and I got another "tracklet" of data ("from this observatory, we saw an object here, then here, then here... at the following times.") I was able to use this to update my estimate of the trajectory.
With that, I got an error message from my software. After a bit of investigation, I had something resembling the following on my computer :
This is a screenshot from my Find_Orb
software, for figuring out trajectories from raw data and determining
where objects are going to go. There's a lot of information packed in
there about the trajectory and the observations and who did the
observing. In this case, the key information is on that red line
about halfway down that says IMPACT in large letters. (That line is
blinking in the actual software. This software is
sometimes used by sleepy people at 3:00 AM on
mountaintops; you don't want them to overlook a possible impact.)
However... everything hinged on that one new tracklet. It made it look likely that the object would hit the moon, but not certain. I also had only a vague idea as to when and where it would hit. The observatory in question almost Never Makes Misteaks, but it would have been embarrassing for me to announce an impact without getting confirming data. This might have been the time where they were actually "off" by a bit.
So (as I occasionally do for bits of junk, and more often for potentially interesting rocks and comets), I posted a request for observations on a mailing list for asteroid/comet observers, explaining the situation. And, that evening and for the next few days while it was still visible, data came in from nine observatories. That simultaneously confirmed the data from the first observatory and really improved the accuracy of the trajectory, so that I could say where and when it would hit with confidence.
After the last sets of data came in on January 20-21, we now just
have to wait until the object becomes observable again on February 7-8.
That will again improve the accuracy of the impact prediction. After
that, we'll probably not get any more data until sometime after
the impact on March 4, if the lunar orbiting satellites can image the
resulting crater. (Actually, there is a small possibility that the
radar that is often used to observe potentially dangerous asteroids
could be used to observe this. There are problems both with observing
something this close -- both "too close" and "too far" are problems
for planetary radar -- and they may not bother; the optical data
will be pretty good, and they've got a lot of targets to chase
already. However, they have the advantage that unlike telescopes,
they can actually observe in the daytime.)
As it turned out, the radar guys were willing to try pinging this object, but ran into some technical issues on the night for which observations were scheduled.
How often does junk hit the moon?
This is the first unintentional case of which I am aware. I keep track of a dozen or so objects in "high", near-moon orbits, mostly so that the folks looking for asteroids will know where they are (and can ignore them; they're looking for rocks, not junk.) In theory, given enough time, such objects will either hit the earth, or the moon, or gain energy by passing the moon and be ejected into orbit around the sun. (That last happened to the booster for the Chang'e 2 mission last summer.)
In each case, I am rooting for a lunar impact. We already know what happens when junk hits the earth; there's not much to learn from that (though junk hitting the earth can be of some scientific interest.) In 2009, a rocket booster was deliberately impacted into the moon in hopes of learning something from the ejecta. In essence, this is a "free" LCROSS... except we probably won't see the impact (it's on the far side of the moon) and it's not in a particularly interesting area; LCROSS was targeted at the south pole, where ice might remain in shadowed craters.
I have particularly hoped for a booster to hit on the near side, in an unlit area, near First or Last Quarter; that would presumably be visible from Earth. But we'd have to get very lucky for that... and when you think that this is the first unintended lunar impact we've had, period, the level of luck required increases.
Better still, perhaps, would be for the folks launching these missions to think about where their boosters are going, and to leave them in orbits that will intersect the moon. I would be a big fan of this, but it does not seem to have been on the radar for either CNSA or NASA.
How much should we worry about this?
Short version : from any 'safety' viewpoint, not at all. (Certainly zero concern from this particular event. From similar junk, there is a very small possible concern; read on.)
Long version : you can perhaps gauge the past level of concern by the fact that, I am (as far as I know) the only person on our green planet computing orbits and making predictions for very high altitude space junk. At that, I do it almost entirely in my spare time. (I did get a small contract to write some software for this a few years back, but that's been about it.) Obviously, junk of this sort hasn't been a big deal. (And I would argue that this level of attention is about right.) As Jonathan McDowell put it : "It's interesting, but not a big deal." Though I should note that Jonathan, like me, is using this as an opportunity to advocate for everybody -- not just SpaceX (or China) -- taking better care of their junk. (Do a search in the linked text for 'DSCOVR'; I don't think I can provide a link directly to the relevant paragraphs.)
I gather there have been some concerns on social media (which, thank the Deity, I'm not on) that the lunar impact might somehow tweak the moon's orbit. Keep in mind that this is a roughly four-ton object that will hit at 2.58 km/s. The moon is fairly routinely hit with larger objects moving in the ballpark of 10-20 km/s; hence, the craters. It's well-built to take that sort of abuse.
For that matter, back in the Apollo era, the later SIV-B boosters were deliberately aimed at the moon. Earlier missions had left seismometers behind; the impacts made "moonquakes" with a well-determined amount of energy at a precisely known time. That helped to calibrate the seismometers. Fifty years later, the moon has remained in its orbit. And, more recently, LCROSS hit the moon (quite deliberately) in 2009 without causing trouble.
Initially, I said there was a small "possible" concern from similar junk. It works like this : an orbit of this sort is "chaotic", in the mathematical sense : any small error in the orbit you determine -- and you can never measure it perfectly -- may get magnified as time goes on; the famed "butterfly effect". Eventually, such objects will either hit the earth (this has happened three times that we know of); pick up speed as it goes past the moon and be ejected into orbit around the sun (this has happened once, last summer, to the Chang'e 2 lunar booster); or it can hit the moon (this is the first time that's happened... again, that we know of; if you're getting the impression this sort of thing isn't carefully tracked, you're right.)
The small concern would be if a piece of junk hit the earth. A very small bit (never really solidly identified) re-entered the atmosphere near Sri Lanka in November 2015. Two Chinese lunar mission boosters, for Queqiao and Chang'e 5, re-entered over the Pacific Ocean. The latter looks as if it was deliberately planned to go past the moon, come back, and plunge in the middle of the ocean, far from land. I am hoping it means CNSA has decided not to leave their junk flying around, but they are unlikely to ever say anything about it.
Such an impact over land would look very dramatic (a bright, slow-moving meteor). I don't think anything would survive re-entry, but would not want to swear to that (I know a lot about figuring out orbits, but not much about the survivability of rocket boosters. Or, if you prefer, I'm not a rocket surgeon.)
Should SpaceX/China be held liable for this?
(Note : we now know that this object is not actually the SpaceX booster; that was a misidentification, by me. I am quite sure this is the upper stage from the Chang'e 5-T1 mission. However, I've left the following paragraphs unaltered, because the point they made remains : without exceptions that I know of, nobody has cared much about where high-altitude junk goes, to the point where I'm the only person keeping track of it, almost entirely in my spare time.)
In truth, it's sheer chance that this happened with a SpaceX booster. It has been common practice to put objects into orbits of this sort. At least three such objects have eventually come back to re-enter the earth's atmosphere, all harmlessly; any of them could have hit the moon instead. There are still several bits of junk we're tracking that may eventually hit the earth or moon or be ejected into orbit around the sun.
Basically, this could have happened with various objects launched by various countries. As mentioned below, high-flying space junk has not been a concern for anybody; it's not just SpaceX.
That said... if an outcome of this event is that some consideration goes into how high-altitude space junk is disposed of, I will not object at all.
What's your involvement in this?
My "day work" is for the asteroid hunting community. The big surveys (Catalina Sky Survey, ATLAS, Pan-STARRS, and ZTF) observe on most clear, moonless nights, imaging the sky for slowly moving objects. Most artificial objects are close to the earth and move fast enough that there is no risk of mistaking them for an asteroid. But there are about a dozen "high-flying" objects that can move slowly enough to look like a rock, at least briefly.
For about fifteen or twenty years now, I've taken these observations and computed orbits. Then, when the surveys find such objects, they can fairly quickly say "never mind; it's not a rock; it's just another nuisance artificial object", and go back to looking for actual rocks.
If it wasn't for that, these objects would go untracked. Objects in lower orbits are very carefully tracked. There are a few tens of thousands being tracked, and they are mostly concentrated in an area a few hundred kilometers above the earth and in the geostationary belt about 35800 km above the equator. There is much more opportunity for one object to hit another, and occasional humans and a lot of valuable spacecraft are at risk. Various militaries want to know what other militaries are doing, and billions of dollars are involved.
High-altitude payloads are carefully tracked. These are almost entirely scientific missions, and you need to know where they're going. For example, NASA can tell you where the James Webb Space Telescope is quite precisely, but they lost interest in its booster once it separated from JWST. (I did not; the JWST booster is being tracked as it goes into orbit around the sun and its orbit computed.) At these altitudes, you go from tens of thousands of objects to a couple of dozen, and it's a much larger volume of space. The risk of impact by junk is not much of a concern.
Generally speaking, high-altitude junk has gone ignored. (Except, it appears, by me.)
I expect this situation to change (and it would appear 18SPCS plans to start tracking cislunar objects.) More lunar and deep-space missions are planned. I don't regard it as a crisis, but I do have some thoughts on how such objects could be better tracked.
Unfortunately, observations will be basically impossible until sometime
around 7 February, while the object is at low elongations. We'll then get
a brief observing window of a day or two, during which it will be bright,
close, and moving fast. Observations then should enable us to refine the
impact point to within a kilometer or so, possibly better... which is good,
because from 10 February to 4 March, it will again be at low elongations
and we aren't going to see anything. (Though
maybe the planetary radar guys will get something; they laugh at daylight and
clouds. It would be an easy target for bistatic radar, but tracking junk is
not really in their purview... I'm hoping they can be persuaded to go after it
anyway.)
After that early February perigee, it goes out very high, to a point almost twice as far away as the moon; then pauses; then comes back and crashes into the far side of the moon.
Is there confirmation that it actually hit?
I'me quite sure it hit at the predicted time and place, give or take a few kilometers. The object is just moving under the influence of gravity (which we can compute almost exactly) and sunlight bouncing off of it (which we can't compute quite as exactly; that's why we might be off by a few kilometers.) It's true that the theory of gravity is "only a theory", but in practice, the theory gives us a good idea as to where orbiting objects will go. Or as Jonathan McDowell put it, "we trust Uncle Isaac - successfully predicting the trajectory of things in space since 1687".
However, people would understandably like to see images of either the impact happening or of the resulting crater ("pictures or it didn't happen").
We didn't expect to be able to get any image of the actual impact. There are two spacecraft that get images of the far side of the moon, NASA's Lunar Reconnaissance Orbiter (LRO) and India's Chandrayaan-2. Those will be able to find the crater. (Since it's on the far side, all the telescopes we have on earth have no chance at all.) Those spacecraft get to see any given part of the moon about once a month, so we'd have had to be really lucky for them to be at the right place at the right time to see the impact. (Repositioning them isn't much of an option; they don't have that much fuel.) And we weren't that lucky.
Both spacecraft ought to get a look in the next month, but I don't know exactly when that would be. This analysis says LRO should get a look on March 28, and Chandrayaan-2 on April 4. (Do a search within the text for "What Now?" to get to the relevant paragraphs). If so, that would mean both of them got a look about a month earlier, shortly before the impact occurred.
I think the AGI people have done the analysis correctly, and I'm getting similar results for LRO using JPL's Horizons system. The only slight hesitation I have here is that I don't know for sure that the trajectory data for the spacecraft is really "current". I've sometimes encountered cases where it turns out the trajectory data was a prediction made a year back, and the actual current trajectory is somewhat different.
But even if the AGI analysts are using an outdated trajectory, the overall idea that we're likely to have to wait a bit still holds. Quite aside from waiting for the spacecraft to get a look at the site, the data has to be downloaded and somebody has to go through the images and find a fresh, new crater. I don't think that last part will take all that long, though; the area to be searched is maybe ten kilometers across, and the crater is about 20 meters across.
Unfortunately, no. The orbit goes well past the moon and has an eccentricity of about 0.89. The 'usual' SGP4/SDP4 model for two-line elements (TLEs) fails in such cases. I have posted "TLEs" for this object; I use these to generate ephemerides and to identify the object from observations... and they work with my code and (probably) nobody else's.
You can get customized ephemerides for your location and desired time span from a tool provided on this site.
I think (but don't know) that the impact itself will have to go unobserved. (Certainly from earth, since the bulk of the moon is in the way, and even if it were on the near side, the impact occurs a couple of days after New Moon.)
I know a fair bit about computing orbits, but not much more than the next guy about which satellites orbiting the moon can do what. I do know that the Lunar Reconnaissance Orbiter (LRO) and Chandrayaan-2 are in low orbits; the odds that they'll be overhead at the right time are pretty lousy. So I don't expect them to see the actual impact. (Maybe they could maneuver, the way spy satellites orbiting the earth can be. But it costs fuel, it may not be considered important enough, and it's a lot harder to say "put the satellite over this point at this time" than to say "I need an image of this point, but I'm not all that particular about when, as long as the sun is lighting it up".)
However, if we can tell the LRO and/or Chandrayaan folks exactly where the crater is, they'll eventually pass over that spot and be able to see a very fresh impact crater and probably learn something about the geology (well, selenology) of that part of the moon. We know the mass of an empty Falcon 9 booster, and that it will hit at 2.58 km/s; the known momentum and energy of the object making the crater ought to help in calibrating the crater size vs. energy function.
Somewhat ironically, the satellite best positioned to observe the actual impact is DSCOVR itself. Except that it's about 600000 km away, and tends to stay focused on the earth; I don't expect they would swerve it sideways to observe an impact that would probably be too faint for it to observe anyway.
Astrometry:
DSCOVR KC2022 01 15.75603 23 58 03.57 -09 30 54.7 17.1 GX J57
DSCOVR KC2022 01 15.76640 23 58 03.16 -09 29 51.0 16.6 GX J57
DSCOVR KC2022 01 15.77722 23 58 03.05 -09 28 43.6 16.7 GX J57
15007B C2022 01 16.06903 00 01 57.97 -09 03 51.8 17.1 718
15007B C2022 01 16.07050 00 01 57.98 -09 03 43.7 16.4 718
15007B C2022 01 16.07123 00 01 57.96 -09 03 38.2 16.9 718
15007B C2022 01 16.07535 00 01 57.91 -09 03 11.2 17.1 718
15007B C2022 01 16.07832 00 01 57.92 -09 02 53.9 17.4 718
15007B C2022 01 16.07906 00 01 57.90 -09 02 49.7 16.7 718
2015-00 KC2022 01 16.73075800 11 11.73 -08 02 48.2 X C95
2015-00 KC2022 01 16.73628500 11 11.94 -08 02 09.7 16.4 GX C95
2015-00 KC2022 01 16.74181100 11 12.19 -08 01 31.4 16.5 GX C95
2015-00 KC2022 01 16.74700200 11 12.52 -08 00 55.9 16.6 GX C95
DSCVR KC2022 01 16.74740 00 11 08.23 -08 01 47.6 16.9 GV 204
2015-00 KC2022 01 16.75183400 11 12.84 -08 00 21.6 16.8 GX C95
DSCVR KC2022 01 16.75351 00 11 09.01 -08 01 04.5 17.0 GV 204
2015-00 KC2022 01 16.75733800 11 13.35 -07 59 43.2 16.3 GX C95
DSCVR KC2022 01 16.75962 00 11 09.86 -08 00 21.1 17.6 GV 204
2015-00 KC2022 01 16.76215900 11 13.80 -07 59 09.0 16.7 GX C95
DSCVR KC2022 01 16.76572 00 11 10.87 -07 59 37.2 17.0 GV 204
2015-00 KC2022 01 16.76695600 11 14.33 -07 58 35.5 16.5 GX C95
2015-00 KC2022 01 16.77177100 11 15.00 -07 57 59.5 16.5 GX C95
DSCVR KC2022 01 16.77183 00 11 12.02 -07 58 53.0 16.7 GV 204
2015-00 KC2022 01 17.72776000 27 30.76 -06 07 55.6 16.9 GX C95
2015-00 KC2022 01 17.73067700 27 31.22 -06 07 28.6 17.7 GX C95
2015-00 KC2022 01 17.73357600 27 31.58 -06 07 04.5 16.3 GX C95
2015-00 KC2022 01 17.73604700 27 31.90 -06 06 43.5 16.6 GX C95
2015-00 KC2022 01 17.73851900 27 32.33 -06 06 23.0 16.7 GX C95
2015-00 KC2022 01 17.74099500 27 32.69 -06 06 01.2 16.5 GX C95
2015-00 KC2022 01 17.74347200 27 33.13 -06 05 39.9 16.4 GX C95
2015-00 KC2022 01 17.74596100 27 33.52 -06 05 18.4 X C95
N40391 KC2022 01 17.74675 00 27 33.93 -06 05 14.1 16.1 VZ K19
2015-00 KC2022 01 17.74842600 27 33.93 -06 04 57.5 X C95
2015-00 KC2022 01 17.75059000 27 34.35 -06 04 38.3 17.2 GX C95
N40391 KC2022 01 17.75171 00 27 34.84 -06 04 31.2 17.1 VZ K19
N40391 KC2022 01 17.75666 00 27 35.78 -06 03 47.9 16.9 VZ K19
N40391 KC2022 01 17.76161 00 27 36.83 -06 03 04.6 17.1 VZ K19
N40391 KC2022 01 17.76649 00 27 37.93 -06 02 21.5 17.1 VZ K19
N40391 KC2022 01 17.77134 00 27 39.14 -06 01 38.5 17.1 VZ K19
N40391 KC2022 01 17.77619 00 27 40.47 -06 00 55.1 17.0 VZ K19
N40391 KC2022 01 17.78105 00 27 41.81 -06 00 11.9 16.9 VZ K19
N40391 KC2022 01 17.78598 00 27 43.30 -05 59 27.2 16.9 VZ K19
2015-007B KCK220117:185918 007.04202 -06.05941 16.6 GV 970
2015-007B KCK220117:190403 007.04752 -06.05120 16.6 GV 970
2015-007B KCK220117:190849 007.05319 -06.04306 16.8 GV 970
WE0913A C2022 01 17.82556 00 27 50.87 -05 53 04.1 15.9 Rq 104
WE0913A C2022 01 17.83328 00 27 55.50 -05 51 50.6 16.3 Rq 104
WE0913A C2022 01 17.84874 00 28 05.79 -05 49 22.9 15.5 Rq 104
N40391 KCK220118:1727287 012.35491 -03.36221 16.5 SZ L34
N40391 KCK220118:1737163 012.36542 -03.33885 16.0 SZ L34
N40391 KCK220118:1749283 012.37961 -03.30924 16.1 SZ L34
2015-00 KC2022 01 18.74675900 50 08.84 -03 23 08.4 16.2 GX C95
2015-00 KC2022 01 18.74778900 50 09.33 -03 22 56.2 15.9 GX C95
2015-00 KC2022 01 18.74880800 50 09.84 -03 22 43.9 16.5 GX C95
N40391 KC2022 01 18.74894 00 50 10.21 -03 22 45.0 16.5 VZ K19
2015-00 KC2022 01 18.74983800 50 10.32 -03 22 30.6 16.1 GX C95
2015-00 KC2022 01 18.75088500 50 10.84 -03 22 17.7 16.0 GX C95
2015-00 KC2022 01 18.75191600 50 11.33 -03 22 05.1 16.1 GX C95
2015-00 KC2022 01 18.75295700 50 11.83 -03 21 52.5 16.0 GX C95
N40391 KC2022 01 18.75298 00 50 12.17 -03 21 54.6 16.6 VZ K19
2015-00 KC2022 01 18.75399300 50 12.32 -03 21 39.2 16.0 GX C95
2015-00 KC2022 01 18.75501200 50 12.90 -03 21 26.4 16.2 GX C95
2015-00 KC2022 01 18.75604200 50 13.40 -03 21 13.3 15.9 GX C95
N40391 KC2022 01 18.75702 00 50 14.20 -03 21 04.1 16.6 VZ K19
2015-00 KC2022 01 18.75708300 50 13.88 -03 21 00.4 15.9 GX C95
2015-00 KC2022 01 18.75811300 50 14.42 -03 20 47.4 15.8 GX C95
N40391 KC2022 01 18.76106 00 50 16.28 -03 20 13.3 16.5 VZ K19
N40391 KC2022 01 18.76509 00 50 18.41 -03 19 22.4 16.6 VZ K19
N40391 KC2022 01 18.76913 00 50 20.60 -03 18 31.4 16.7 VZ K19
N40391 KC2022 01 18.77317 00 50 22.86 -03 17 40.2 16.5 VZ K19
N40391 KC2022 01 18.77721 00 50 25.20 -03 16 48.8 16.6 VZ K19
N40391 KC2022 01 18.78125 00 50 27.61 -03 15 56.9 16.6 VZ K19
N40391 KC2022 01 19.79388 01 31 11.77 +01 40 05.0 15.7 VZ K19
N40391 KC2022 01 19.79517 01 31 14.32 +01 40 38.5 15.6 VZ K19
N40391 KC2022 01 19.79646 01 31 16.86 +01 41 11.7 15.4 VZ K19
N40391 KC2022 01 19.79971 01 31 23.40 +01 42 35.6 16.0 VZ K19
N40391 KC2022 01 19.80032 01 31 24.61 +01 42 51.1 15.1 VZ K19
N40391 KC2022 01 19.85776 01 33 36.28 +02 08 06.3 15.7 VZ K19
N40391 KC2022 01 19.85983 01 33 41.72 +02 09 02.1 15.7 VZ K19
N40391 KC2022 01 19.86190 01 33 47.15 +02 09 58.0 15.9 VZ K19
N40391 KC2022 01 19.86398 01 33 52.71 +02 10 54.2 15.8 VZ K19
N40391 KC2022 01 19.86605 01 33 58.29 +02 11 50.2 15.8 VZ K19
N40391 KC2022 01 19.86812 01 34 03.94 +02 12 46.4 15.8 VZ K19
N40391 KC2022 01 19.87020 01 34 09.60 +02 13 42.8 15.7 VZ K19
N40391 KC2022 01 19.87227 01 34 15.34 +02 14 39.1 15.8 VZ K19
N40391 KC2022 01 19.87434 01 34 21.12 +02 15 35.8 15.8 VZ K19
2015-00 KC2022 01 19.88390601 34 48.13 +02 20 03.5 15.2 GX C95
2015-00 KC2022 01 19.88556701 34 52.98 +02 20 49.5 15.5 GX C95
2015-00 KC2022 01 19.88849001 35 01.71 +02 22 08.4 15.8 GX C95
2015-00 KC2022 01 19.89122701 35 09.91 +02 23 24.8 15.8 GX C95
N40391 KC2022 01 20.73975 04 28 16.63 +18 01 37.2 12.2 VZ K19
N40391 KC2022 01 20.73989 04 28 21.58 +18 01 59.7 12.8 VZ K19
N40391 KC2022 01 20.74003 04 28 26.57 +18 02 22.6 13.5 VZ K19
N40391 KC2022 01 20.74178 04 29 29.49 +18 07 13.6 12.2 VZ K19
N40391 KC2022 01 20.74192 04 29 34.60 +18 07 36.9 12.3 VZ K19
N40391 KC2022 01 20.74206 04 29 39.74 +18 08 00.5 12.9 VZ K19
N40391 KC2022 01 20.74409 04 30 53.74 +18 13 39.2 12.9 VZ K19
N40391 KC2022 01 20.74423 04 30 58.96 +18 14 03.3 13.7 VZ K19
N40391 KC2022 01 20.74437 04 31 04.17 +18 14 26.8 14.2 VZ K19
2015-007B KCK220120:18340858 072.84231 +18.88656 13.4 GV J95
2015-007B KCK220120:18344030 072.91189 +18.90353 12.2 GV J95
2015-007B KCK220120:18351395 072.98583 +18.92154 13.0 GV J95
2015-007B KCK220120:18363279 073.15992 +18.96363 12.2 GV J95
2015-007B KCK220120:18370950 073.24140 +18.98326 13.2 GV J95
2015-007B KC2022 01 20.77664404 53 04.83 +19 47 45.4 12.8 GX C95
2015-007B KC2022 01 20.77733204 53 36.22 +19 49 48.4 11.9 GX C95
2015-007B KC2022 01 20.77767404 53 51.99 +19 50 48.9 12.7 GX C95
2015-007B KC2022 01 20.77800904 54 07.41 +19 51 48.8 12.4 GX C95
2015-007B KC2022 01 20.77835104 54 23.22 +19 52 48.7 11.7 GX C95
2015-007B KC2022 01 20.77937504 55 10.76 +19 55 51.2 11.6 GX C95
2015-007B KC2022 01 20.78005804 55 42.53 +19 57 51.8 12.9 GX C95
Station data:
(104) San Marcello Pistoiese (N44.063034 E10.804200) Italy. Observers P.
Bacci, M. Maestripieri. Measurers P. Bacci, L. Tesi, G. Fagioli. 0.60-m
f/4 reflector + CCD.
(204) Schiaparelli Observatory (N45.868330 E8.769930) Italy.
Observer L. Buzzi. 0.84-m f/3.5 reflector + CCD.
(718) Tooele (N40.641406 W112.295800) US/Utah. Observer P. Wiggins. 0.35-m
f/5.5 Schmidt-Cassegrain + CCD.
(970) Chelmsford (N51.744713 E0.495400) UK/England. Observer N. James.
0.28-m f/10 Schmidt-Cassegrain + CCD.
(C95) SATINO Remote Observatory, Haute Provence (N43.932040 E5.712390)
France. Observer J. Jahn. 0.60-m f/3.2 Newtonian reflector + CCD.
(J57) Centro Astronómico Alto Turia, Valencia (N39.950157 W1.109110) Spain.
Observer A. Fornas. Measurers A. Fornas, G. Fornas, E. Arce, V. Mas.
Reflector 0.4m + CCD.
(J95) Great Shefford (N51.474969 W1.447003) UK/England. Observer P.
Birtwhistle. 0.41-m f/6.3 Schmidt-Cassegrain + CCD.
(K19) PASTIS Observatory, Banon (N43.999459 E5.647310) France. Observer C.
Demeautis. 0.28-m f/2.2 reflector + CCD.
(L34) Galhassin Robotic Telescope, Isnello (N37.939358 E14.020610) Italy.
Observer A. Nastasi. 0.40-m reflector + CCD.
Orbital elements: WE0913A = DSCOVR object = 2015-007B = NORAD 40391
Perigee 2022 Jan 20.9916485 +/- 6.77e-6 TT = 23:47:58.43 (JD 2459600.4916485)
A1: 1.68e-8 +/- 2.85e-8 A2: 7.55e-9 +/- 1.14e-8 A3: 2.7e-9 +/- 4.33e-9 AU/day^2 [1/r^2]
Epoch 2022 Jan 21.0 TT = JDT 2459600.5 Find_Orb
M 0.1621535087 +/- 0.00017 (J2000 equator)
n 19.4160785231 +/- 0.0095 Peri. 149.2278077 +/- 0.0037
a295911.94259 +/- 96.5 Node 17.8212832 +/- 0.0006
e 0.889824677 +/- 3.05e-5 Incl. 27.0092517 +/- 0.00006
P 18.54d H 26.3 G 0.15 U 9.6
q 32602.193723 +/- 2.09 Q 559221.69147 +/- 191
From 111 observations 2022 Jan. 15-20; mean residual 0".731
Residuals in arcseconds: 220115 J57 .254+ .117+ 220117 K19 .644- .158+ 220119 K19 .213- .560+ 220115 J57 .308+ .222+ 220117 K19 .356- .032+ 220119 K19 .126+ .702+ 220115 J57 .298+ .124- 220117 K19 .440+ .059+ 220119 K19 .212- .459+ 220116 718 .801- .928+ 220117 K19 1.9m- .447- 220119 K19 .314- .369+ 220116 718 .136- .281- 220117 K19 .061+ .327- 220119 K19 .152+ .334+ 220116 718 .207- .586+ 220117 970 .307+ .233- 220119 K19 .313- .311+ 220116 718 .076- 1.32+ 220117 970 .166+ .138+ 220119 K19 .020- .231+ 220116 718 .267+ .444- 220117 970 1.6m+ .055+ 220119 K19 .173+ .133+ 220116 718 .039- 1.01- 220117 104 .318+ .938+ 220119 K19 .608+ .147+ 220116 C95 .648- .627- 220117 104 .294+ .940+ 220119 K19 .035- 765µ+ 220116 C95 .178- .192+ 220117 104 .406- .279+ 220119 K19 .107+ .063- 220116 C95 .164- .458+ 220118 L34 .280- .617+ 220119 K19 .018+ .185+ 220116 C95 .231+ .092- 220118 L34 .374- .277- 220119 C95 .473+ .376+ 220116 204 .246- .132+ 220118 L34 .169- .342- 220119 C95 .233- .677+ 220116 C95 .170- .375+ 220118 C95 .169- .462+ 220119 C95 .064+ .985- 220116 204 .040+ .107+ 220118 C95 .162- .135- 220119 C95 .891- .187- 220116 C95 .337+ .082- 220118 C95 .176+ .508- 220120 K19 .688- .032- 220116 204 .324- 8.2m- 220118 K19 .315+ .180+ 220120 K19 1.40- .711- 220116 C95 .277- .190- 220118 C95 .062- .031- 220120 K19 1.61- 1.00- 220116 204 .073- .068+ 220118 C95 .126+ .178- 220120 K19 1.64- .469- 220116 C95 .747- 1.07- 220118 C95 .070- .439- 220120 K19 .971- .458- 220116 C95 .303- .167+ 220118 C95 .240- .837- 220120 K19 .059+ .154- 220116 204 .349+ 2.3m+ 220118 K19 .175+ .217+ 220120 K19 .321+ .088- 220117 C95 .782- 1.59- 220118 C95 .576- .485- 220120 K19 1.50+ .600+ 220117 C95 .314+ .772+ 220118 C95 .510+ .434- 220120 K19 2.48+ .681+ 220117 C95 .312- .287+ 220118 C95 .263+ .232- 220120 J95 .302- .195- 220117 C95 .871- .254+ 220118 K19 .292+ .160+ 220120 J95 .175- .061- 220117 C95 4.6m- .360- 220118 C95 .421- .381- 220120 J95 .277- .085+ 220117 C95 .414- .220+ 220118 C95 .178- .305- 220120 J95 .315- .046- 220117 C95 .137+ .221+ 220118 K19 .319+ .210+ 220120 J95 .208- .035- 220117 C95 .330- .248+ 220118 K19 .289+ .297+ 220120 C95 3.28+ .074- 220117 K19 .034+ .443+ 220118 K19 .146+ .169+ 220120 C95 2.02+ .951+ 220117 C95 .686- .188- 220118 K19 .072+ .054+ 220120 C95 2.92+ .784+ 220117 C95 .313- .224+ 220118 K19 .171+ .045- 220120 C95 2.89+ 1.24+ 220117 K19 .116+ .311+ 220118 K19 .246+ .172+ 220120 C95 3.27+ .426+ 220117 K19 .399- .389+ 220119 K19 .174+ .204+ 220120 C95 3.95+ 1.02+ 220117 K19 .415- .197+ 220119 K19 .150+ .549+ 220120 C95 2.50+ .195+ Ephemerides (geocentric): Date (UTC) RA Dec delta elong mag " sig PA ---- ----- ------------ ------------ ------ ----- --- -------- 2022 01 18 00 33 37.259 -04 45 50.64 372112 68.5 17.4 .261 15 2022 01 19 00 58 50.853 -01 35 02.07 294160 74.5 16.6 .594 76 2022 01 20 01 47 47.879 +04 37 17.89 187576 87.1 15.0 6.62 63 2022 01 21 11 44 19.798 +10 41 30.25 32704 128.0 9.8 98.9 115 2022 01 22 20 34 14.822 -25 29 03.38 189943 7.1 32?? 91.9 80 2022 01 23 21 31 52.747 -22 37 02.63 296133 17.1 24?? 84.5 75 2022 01 24 22 00 31.024 -20 38 12.60 374337 22.7 23?? 83.2 72 2022 01 25 22 19 40.096 -19 06 22.39 434713 26.3 22?? 84.0 70 2022 01 26 22 34 19.778 -17 49 21.53 481700 29.0 22?? 85.8 69 2022 01 27 22 46 29.209 -16 41 04.92 517670 31.0 22?? 88.6 68 2022 01 28 22 57 07.875 -15 38 01.38 544006 32.7 21?? 92.2 67 2022 01 29 23 06 50.400 -14 37 52.06 561524 34.2 21?? 96.8 67 2022 01 30 23 15 59.617 -13 38 53.69 570669 35.6 21?? 103 66 2022 01 31 23 24 52.518 -12 39 38.82 571604 36.9 21?? 110 66 2022 02 01 23 33 43.524 -11 38 42.16 564246 38.3 21?? 120 65 2022 02 02 23 42 46.759 -10 34 27.46 548249 39.7 20?? 133 65 2022 02 03 23 52 18.100 -09 24 49.23 522908 41.3 20?? 150 64 2022 02 04 00 02 37.519 -08 06 28.74 486823 43.1 20?? 174 64 2022 02 05 00 14 22.312 -06 29 35.99 436532 45.3 19?? 206 61 2022 02 06 00 31 06.828 -03 45 51.66 366976 49.1 19?? 355 51 2022 02 07 00 59 59.244 +01 11 22.63 279168 56.5 17?? 773 47 2022 02 08 02 05 43.110 +12 05 44.81 164630 74.6 15.3 2298 50 2022 02 09 13 40 42.373 -08 04 56.60 56663 113.6 11.5 235' 124 2022 02 10 19 13 40.625 -34 22 47.77 199629 37.2 19?? 544 10 2022 02 11 20 24 37.352 -32 19 02.93 304771 24.5 22?? 759 38 2022 02 12 20 59 52.824 -30 16 32.31 386470 19.0 24?? 805 40 2022 02 13 21 22 45.006 -28 33 44.76 452797 15.9 26?? 805 40 2022 02 14 21 39 37.627 -27 05 20.32 507681 14.1 27?? 791 40 2022 02 15 21 53 04.489 -25 46 47.44 553391 12.9 28?? 772 40 2022 02 16 22 04 21.378 -24 35 01.41 591379 12.2 29?? 753 40 2022 02 17 22 14 11.007 -23 27 54.49 622626 11.7 29?? 735 40 2022 02 18 22 22 59.921 -22 23 53.80 647821 11.5 29?? 717 40 2022 02 19 22 31 05.957 -21 21 47.83 667450 11.3 30?? 699 40 2022 02 20 22 38 41.924 -20 20 38.08 681850 11.2 30?? 684 41 2022 02 21 22 45 57.602 -19 19 33.68 691240 11.2 30?? 669 41 2022 02 22 22 53 00.921 -18 17 47.46 695744 11.3 30?? 657 42 2022 02 23 22 59 58.718 -17 14 32.74 695395 11.4 30?? 647 43 2022 02 24 23 06 57.295 -16 09 00.32 690149 11.6 29?? 639 44 2022 02 25 23 14 02.894 -15 00 14.85 679879 11.9 29?? 636 46 2022 02 26 23 21 22.196 -13 47 10.21 664374 12.3 29?? 639 47 2022 02 27 23 29 02.945 -12 28 22.62 643323 12.9 28?? 649 49 2022 02 28 23 37 14.867 -11 01 59.62 616291 13.8 28?? 672 51 2022 03 01 23 46 11.148 -09 25 21.25 582675 14.9 27?? 712 53 2022 03 02 23 56 11.016 -07 34 25.48 541605 16.4 26?? 781 55 2022 03 03 00 07 44.204 -05 22 40.08 491718 18.4 25?? 898 56 2022 03 04 00 21 33.646 -02 38 53.82 430220 21.3 24?? 1076 57 RA/decs are astrometric J2000 coordinates (corrected for light time lag, but in the inertial J2000 frame, i.e., not rotated for precession or nutation, and differential light deflection is not included.) Display can be turned on/off in the 'advanced options' for ephemerides. When turning them on, you can select from various format choices (base-60, decimal, different precisions, etc.) Distances are in kilometers for distances under one million km (about 0.00668 AU), and in AUs for larger distances.