Tianwen-1 Real-time Orbit

Waiting for the lander to land

Tianwen-1 Real-time Orbit

Waiting for the lander to land
Lander remaining time to land

12 Days

Estimated flight less thanhalf month

Distance to Mars

0.0002 AU

About 35,904 KM away

Task phase period (days)
* The planetary trajectory and Tianwen-1 trajectory data are from NASA JPL Horizons.

How to calculate the orbit of Tianwen-1?

The detailed code for simulating orbit calculation through Python has been open sourced to GitHub, you can click here View the source code.

The Tianwen-1 Mars Rover from Earth to Mars uses an improved Hohmann transfer track (fast transfer track), the starting point is at the time of departure The earth, the ending point is Mars at the time of arrival, and the focus is on the elliptical trajectory between the earth and the sun at the time of departure.

On the NASA JPL Horizons website, we can query planetary trajectories and position data , And then establish the coordinates of the Earth when the Tianwen-1 probe departs and the coordinates of Mars when it arrives. According to the fast transfer orbit, an ellipse can be drawn (as shown in the figure below). After curve simulation, you can use Elliptic equation and one-dimensional quadratic equation to solve all the coordinate points on the curve, which is the trajectory of Tianwen-1.

Note: 1. Up to now, the track of Tianwen-1 can also be found on NASA JPL Horizons, and the data is more real and accurate. The running example on the website has been replaced with this data; 2. Thanks to the Weibo blogger @haibaraemily gave me professional knowledge suggestions, and at the same time it introduced the Hörmann transfer track and fast The difference between the transfer trajectory; 3. The example in the open source project is to calculate the trajectory from the perspective of principle, which is for learning reference only

Python simulation orbit-OGWW

From @haibaraemily weibo


Picture is from Baike, datas are from wiki

Basic Information

Names Tianwen-1
Mission type Planetary science with an orbiter, lander and rover
Mission objectives Search for evidence of both current and past life, and to assess the planet's environment
Mission duration 14d 20h 22m (since launch) Orbiter: 2 Earth years (planned) Rover: 90 sols (planned)
Launch date 23 July 2020, 04:41:15 UTC
Rocket Long March 5
Launch site Wenchang, LC-101
Contractor China Aerospace Science and Technology Corporation

Spacecraft Properties

Type Orbiter, lander, rover
Orbiter date 11 to 24 February 2021
Lander date 23 April 2021 (proposed); Utopia Planitia (2 preliminary sites)
Rover date After 23 April 2021 (proposed); Utopia Planitia (2 preliminary sites)