Possible dark flight parameters of the Okulovka meteorite

Introduction

On October 27, 2025 at 6:32 local time, a spectacular fireball passed over the Novgorod region of Russia. The meteorite from the fall – currently the only one – was found in early November, crashing into a roof structure. I participated in the prediction of the strewn field with my program – Metlab. Below, I will try to determine the possible limits of certain parameters of the dark flight using the computer model, taking into account the position of the only known meteorite.

Details

This is the second year that I have been trying to help the Polish Skytinel network, and since then we have been modeling the strewn field of all possible meteorite falls with Mateusz Zmija. Since we wrote different programs for the calculation and used different sources for the upper atmosphere winds, if our results are largely the same, it probably means something good. This was the case in the Okulovka fall.

I received the calculated data of the trajectory on October 30, when we made the first strewn field maps starting from different heights. The end of the trajectory was recorded by a camera with relatively poor resolution and from a big distance, so we could not be sure that the real end of the trajectory could be seen. The last definitely measured position was at an altitude of 30 km, so we made strewn fields for altitudes of 30-25-20 km by extrapolating the trajectory.

We learned about the found meteorite and its position at the beginning of November, as the finder requested that the exact location be kept secret, so it will not be included in this article. The dynamic mass calculation gave a result of 5 – 15 kg for the final pieces. My goal was to find an optimal solution for which the extrapolation of the trajectory is the shortest in the given mass range. It seems certain that the approx. 410 g found was a part detached from a larger piece during dark flight, which may have originally been of greater (~500g) mass. Unfortunately, as long as only one meteorite is found in the strewn field, neither the size of this larger piece nor the height of its separation can be determined precisely.

Legend to the images:

• blue – pieces that have switched to dark flight higher along the trajectory
• white – pieces starting from the end of the trajectory
• red – pieces detached during the dark flight
• square symbol – the shape of the meteorite is more square
• round symbol – the shape of the meteorite is more rounded
• The number of points displayed does not reflect the probability of the pieces there

 

 

 

 

Conclusion

The results obtained show that the trajectory must be extrapolated at least 4 kilometers further if the main mass was 5 kg. In the case of a 15 kg mass, only a 2.5 km extension is sufficient. In addition, in the case of a smaller main mass, the height region for separation during the dark flight is also 3 km narrower. Based on these, it is more likely that the main mass is more like 10 kg. Of course, each mass can be answered using the model, this is just a more likely case out of all possible events. How could be possible that the trajectory is 2-3 km longer than the measurement from the footage? As I mentioned earlier, the only footage was taken from a long distance (>300km) of the end of the fall, and also with low resolution and low FPS. This in itself is enough to explain, however, the fall occurred at dawn on the site, almost in a blue sky, which could also have suppressed the fading end of the trajectory.

 

Acknowledgements

We would like to thank Stanisław Korotkij and Yevgeny Trofimov for providing the recordings and data that allowed us to conduct analyses of the event.

References

The Metlab software: eMetN Meteor Journal, ISSN 3041-4261, Online publication https://www.emeteornews.net, vol. 9, no. 6, p. 410-414.
Skytinel Team, Mateusz Zmija: “Moscow fireball and meteorite fall in Novgorod Oblast”  https://skytinel.com/moskiewski-bolid-i-spadek-meteorytow-w-obwodzie-nowogrodzkim/