Image: Time Dilation vs Orbital Height

Description: Depicts the time dilation as a function of orbital height relative to a stationary observer on Earth. It is common to consider the total dilation as being due to two distinct effects: Kinematic time dilation (customarily referred to as the Special Relativity effect) accounts for slowed time in orbit (relative to the observer on Earth) depending on the orbital velocity associated to a specific orbital height. Gravitational time dilation (customarily referred to as the General Relativity effect) accounts for accelerated time (relative to the observer on Earth) due to the distance to the Earth's gravitational center. Although these sources of time dilation are regularly referred to as "SR time dilation" and "GR time dilation", this usage is incorrect, because general relativity accounts for both effects. The point for "GPS" has been firmly confirmed by decades of measurement, both by satellites of the U.S. Global Positioning System as well as by the satellites of the Russian GLONASS and European Galileo systems in similar orbits. Geosynchronous time dilation has been firmly confirmed by the Chinese Beidou and the Indian Regional Satellite Systems, which use geostationary satellites to improve accuracy above their respective countries. Also included is the measurement at peak altitude of the 1976 Gravity Probe A experiment, which measured time dilation effects throughout most of its nearly vertical trajectory. Time dilation for the ISS (which has orbited at various altitudes, hence the elongated mark) has not yet been confirmed by actual measurement, but this should change with the launching of the Atomic Clock Ensemble in Space (ACES) mission in 2020.
Title: Time Dilation vs Orbital Height
Credit: Own work
Author: Prokaryotic Caspase Homolog
Usage Terms: Creative Commons Attribution-Share Alike 4.0
License: CC BY-SA 4.0
License Link: https://creativecommons.org/licenses/by-sa/4.0
Attribution Required?: Yes