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| Click diagram to enlarge |
Last update: 27 April 2025 09:00 UTC
(this post will be periodically updated with new reentry forecasts)
* The current nominal forecast is reentry on 10 May 2025 04:52 UTC ± 3.3 days *
In the second week of May 2025,
an unusual object will reenter. It concerns the
Kosmos 482 Descent Craft (1972-023E, cat. nr. 6073).
This object is
the lander module from a 1972 failed Soviet Venera mission. I published an extended discussion and analysis of this object and its history
three years ago in The Space Review.
As this is a lander that was
designed to survive passage through the Venus atmosphere, it is
possible that it will survive reentry through the Earth atmosphere intact, and impact intact. There are many uncertain factors in this though, including that this will be a long shallow reentry trajectory and the age of the object.
The risks involved are not particularly high, but not zero: with a mass of just under 500 kg and 1-meter size, risks are similar to that of a meteorite impact. A TUDAT reentry analysis suggests an impact speed (after atmospheric deceleration) of about 65-70 meter per second (~242 km/h), assuming it did not break up or extensively ablate during reentry (see the diagram below: note the logarithmic scale of the x-axis)
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| Click diagram to enlarge |
The diagram below shows the change in altitude of apogee and perigee over the past 1.5 years: notably apogee has been coming down steadily, but in the past few months, perigee has started to come down too. On April 27, the object was in a 386 x 155 km orbit.
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| Click diagram to enlarge |
The reentry is an uncontrolled reentry. At the moment, we cannot say with any degree of certainty when and where it exactly will reenter.
With an orbital inclination of 51.7 degrees, the reentry can occur
anywhere between latitude 52 N and 52 S, and from our current modelling (see below) the reentry should happen near May 10th, 2025 (but this is dependent on a.o. how solar activity develops in the coming two weeks), give or take a few days. The uncertainty in the reentry date will decrease once we will get closer to the actual reentry, but even on the day itself uncertainties will remain large.
Over the past months, together with my colleague Dominic Dirkx, we have been developing a reentry model for this object in TUDAT.
TUDAT, the
TU Delft Astrodynamics Toolbox is open source, multi-platform Astrodynamics software developed and maintained at
the Aerospace faculty of Delft Technical University (where I work). The TUDAT script we use for our analysis
is here, while the TUDAT software itself
is available here.
The Kosmos 482 Descent Craft is probably similar to the descent craft of Venera 8 (which was launched only a few days earlier in 1972). Literature values suggest that the object is about 1 meter in size and semi-globular, with a mass of ~495 kg. Using our TUDAT model and a 1-meter diameter, and the NRLMSISE00 model atmosphere with historic space weather data, we find that the orbital evolution of the object from mid-1972 to early 2025 is actually best matched when we use a mass of 480 kg, 15 kg less than the literature value. All our forecast predictions are therefore done using a mass of 480 kg.
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| Click diagram to enlarge |
The diagrams in top of this post and below (which I will periodically update) give the evolution of our reentry predictions, based on orbits issued for the object since November 2024. Over the past few months, the model consistently points to reentry within a few days of 9-10 May 2025.
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| Click diagram to enlarge |
Below is the evolution of the reentry forecast in tabular form,
latest forecast at the bottom (
I will periodically update this table with new forecasts, more frequently so when the reentry dates comes nearer):
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TUDAT REENTRY FORECAST EVOLUTION for KOSMOS 482 Descent Craft
Date/times in UTC
REFERENCE ORBIT ORBIT EPOCH REENTRY FORECAST +/-
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15-11-2024 05:43 24320.23870400 05-05-2025 23:33 42.9 days
01-12-2024 05:32 24336.23116452 08-05-2025 09:09 39.5 days
15-12-2024 18:58 24350.79080401 07-05-2025 11:51 35.7 days
01-01-2025 11:20 25001.47260254 09-05-2025 07:20 32.0 days
15-01-2025 03:23 25015.14140884 10-05-2025 20:40 28.9 days
02-02-2025 08:54 25033.37115746 13-05-2025 17:52 25.1 days
15-02-2025 03:20 25046.13941015 11-05-2025 09:52 21.3 days
01-03-2025 00:07 25060.00535989 10-05-2025 17:51 17.7 days
15-03-2025 05:56 25074.24770046 10-05-2025 07:57 14.0 days
30-03-2025 12:05 25089.50360681 09-05-2025 21:11 10.1 days
13-04-2025 21:32 25103.89775709 09-05-2025 22:01 6.5 days
20-04-2025 01:39 25110.06916305 09-05-2025 11:31 4.9 days
22-04-2025 21:24 25112.89204293 09-05-2025 12:48 4.2 days
23-04-2025 22:57 25113.95657237 09-05-2025 19:43 4.0 days
27-04-2025 00:27 25117.01893077 10-05-2025 04:52 3.3 days
Here is footage I shot of the object with my tracking camera in Leiden in 2020:
