International space station maneuvers

This page is periodically updated with data about the ISS maneuvers starting from 2021-10-12. For the older maneuvers, please see this page.

The values are obtained from NASA "ISS.OEM_J2K_EPH.txt" data file downloadable from nasa-public-data and from the TLEs downloaded from Space-Track.org. Please, note that not all figures are significant.
All the TLEs are processed with the SGP4 C++ library v2020-09-10 published by David Vallado and freely downloadable from CelesTrak.

Select a maneuver:

The graph shows:

the radius vector minus 6371 km (just to show an approximate altitude) and the orbital speed before and after the maneuver;
two vertical green lines representing the start and end of the maneuver;
four points showing the semi-major axis (or mean radius vector) minus 6371 km and mean orbital speed of the last and penultimate orbit before the maneuver and the first and second orbit after the maneuver;
four dashed horizontal lines representing the mean radius vector - 6371 km and mean orbital speed of the last two orbits before the maneuver and the first two orbits after the maneuver.

NASA data file: CREATION_DATE =

Start   :  UTC
Duration: ^m ^s
ΔV      :  m/s
Δsma    :  m (variation of the semi-major axis)
ΔRmin   :  m
ΔRmax   :  m

Here's the osculating inclination before and after the maneuver.
The variation of the inclination during one orbit is caused by the Earth's flattening.

Δi: deg (variation of the osculating inclination).

The J2000 ISS state contained in the NASA data file is converted to the TEME reference frame, then the osculating inclination is calculated. The inclination shown in the graph, therefore, is to the true (instantaneous) equator.

The graph shows the 1-orbit averaged radius vector (or semi-major axis) and orbital speed.

ΔV = m/s
Δsma = m (variation of the semi-major axis)

Here are the perigee and apogee radius vector.
For any given TLE, the program calculates the ISS orbital period T. Then the smallest and the biggest radius vector is found from the TLE epoch minus T/2 to the TLE epoch plus T/2.

Δperigee: m
Δapogee: m

Here is the instantaneous radius vector before and after the maneuver.

Δperigee: m
Δsma: m
Δapogee: m

The graph shows the ISS altitude above the WGS 72 ellipsoid for the same TLEs used in the previous graph.