Apogee and Perigee Distance Calculator
The Apogee and Perigee Distance Calculator is used to calculate the farthest and the closest distance of an object (satellite or moon) from the Earth. According to Kepler’s First Law, the orbit of a satellite revolving around the Earth is elliptical with the center of the Earth lying at one of the foci of the ellipse. This elliptical orbit is defined by its semi-major axis ‘a’ and eccentricity ‘e’.
Perigee refers to the point on the orbit of a satellite that is at the nearest distance from the center of the Earth. The perigee distance is computed from the values of eccentricity ‘e’ and the semi-major axis ‘a’ of an elliptical satellite orbit.
Apogee refers to the point on the orbit of a satellite that is at the farthest distance from the center of the Earth. The apogee distance is computed from the values of eccentricity ‘e’ and the semi-major axis ‘a’ of an elliptical satellite orbit.
The eccentricity of the ellipse is the ratio of the distance between the center of the ellipse and either of its foci (= ae) to the semi-major axis of the ellipse. The semi-major axis of the ellipse represents the longest radius of the ellipse. Two important parameters of an elliptical satellite orbit which are the apogee and perigee are calculated using the semi-major axis ‘a’ and eccentricity ‘e’.
GNSS Constellations - A list of all GNSS satellites by constellations
beidou
| Satellite Name | Orbit | Date |
|---|
| BeiDou-3 G4 | Geostationary Orbit (GEO) | 17 May, 2023 |
| BeiDou-3 G2 | Geostationary Orbit (GEO) | 09 Mar, 2020 |
| Compass-IGSO7 | Inclined Geosynchronous Orbit (IGSO) | 09 Feb, 2020 |
| BeiDou-3 M19 | Medium Earth Orbit (MEO) | 16 Dec, 2019 |
| BeiDou-3 M20 | Medium Earth Orbit (MEO) | 16 Dec, 2019 |
| BeiDou-3 M21 | Medium Earth Orbit (MEO) | 23 Nov, 2019 |
| BeiDou-3 M22 | Medium Earth Orbit (MEO) | 23 Nov, 2019 |
| BeiDou-3 I3 | Inclined Geosynchronous Orbit (IGSO) | 04 Nov, 2019 |
| BeiDou-3 M23 | Medium Earth Orbit (MEO) | 22 Sep, 2019 |
| BeiDou-3 M24 | Medium Earth Orbit (MEO) | 22 Sep, 2019 |
galileo
| Satellite Name | Orbit | Date |
|---|
| GSAT0223 | MEO - Near-Circular | 05 Dec, 2021 |
| GSAT0224 | MEO - Near-Circular | 05 Dec, 2021 |
| GSAT0219 | MEO - Near-Circular | 25 Jul, 2018 |
| GSAT0220 | MEO - Near-Circular | 25 Jul, 2018 |
| GSAT0221 | MEO - Near-Circular | 25 Jul, 2018 |
| GSAT0222 | MEO - Near-Circular | 25 Jul, 2018 |
| GSAT0215 | MEO - Near-Circular | 12 Dec, 2017 |
| GSAT0216 | MEO - Near-Circular | 12 Dec, 2017 |
| GSAT0217 | MEO - Near-Circular | 12 Dec, 2017 |
| GSAT0218 | MEO - Near-Circular | 12 Dec, 2017 |
glonass
| Satellite Name | Orbit | Date |
|---|
| Kosmos 2569 | -- | 07 Aug, 2023 |
| Kosmos 2564 | -- | 28 Nov, 2022 |
| Kosmos 2559 | -- | 10 Oct, 2022 |
| Kosmos 2557 | -- | 07 Jul, 2022 |
| Kosmos 2547 | -- | 25 Oct, 2020 |
| Kosmos 2545 | -- | 16 Mar, 2020 |
| Kosmos 2544 | -- | 11 Dec, 2019 |
| Kosmos 2534 | -- | 27 May, 2019 |
| Kosmos 2529 | -- | 03 Nov, 2018 |
| Kosmos 2527 | -- | 16 Jun, 2018 |
gps
| Satellite Name | Orbit | Date |
|---|
| Navstar 82 | Medium Earth Orbit | 19 Jan, 2023 |
| Navstar 81 | Medium Earth Orbit | 17 Jun, 2021 |
| Navstar 78 | Medium Earth Orbit | 22 Aug, 2019 |
| Navstar 77 | Medium Earth Orbit | 23 Dec, 2018 |
| Navstar 76 | Medium Earth Orbit | 05 Feb, 2016 |
| Navstar 75 | Medium Earth Orbit | 31 Oct, 2015 |
| Navstar 74 | Medium Earth Orbit | 15 Jul, 2015 |
| Navstar 73 | Medium Earth Orbit | 25 Mar, 2015 |
| Navstar 72 | Medium Earth Orbit | 29 Oct, 2014 |
| Navstar 71 | Medium Earth Orbit | 02 Aug, 2014 |
irnss
| Satellite Name | Orbit | Date |
|---|
| NVS-01 | Geostationary Orbit (GEO) | 29 May, 2023 |
| IRNSS-1I | Inclined Geosynchronous Orbit (IGSO) | 12 Apr, 2018 |
| IRNSS-1H | Sub Geosynchronous Transfer Orbit (Sub-GTO) | 31 Aug, 2017 |
| IRNSS-1G | Geostationary Orbit (GEO) | 28 Apr, 2016 |
| IRNSS-1F | Geostationary Orbit (GEO) | 10 Mar, 2016 |
| IRNSS-1E | Geosynchronous Orbit (IGSO) | 20 Jan, 2016 |
| IRNSS-1D | Inclined Geosynchronous Orbit (IGSO) | 28 Mar, 2015 |
| IRNSS-1C | Geostationary Orbit (GEO) | 16 Oct, 2014 |
| IRNSS-1B | Inclined Geosynchronous Orbit (IGSO) | 04 Apr, 2014 |
| IRNSS-1A | Inclined Geosynchronous Orbit (IGSO) | 01 Jul, 2013 |
