Dominic Ford, Editor
From the Earth feed
The Earth's annual orbit around the Sun will carry it to its furthest point from the Sun – its aphelion – at a distance of 1.02 AU.
The Earth's distance from the Sun varies by around 3% over the course of the year because its orbit is slightly oval-shaped, following a path called an ellipse. In practice, this variation is rather slight, however, because the Earth's orbit is very nearly circular.
The Earth completes one revolution around this oval-shaped orbit each year, and so it recedes to its greatest distance from the Sun on roughly the same day every year. In 2017, this falls on 3 July.
Technically speaking, this marks the moment when the Sun appears smaller in the sky than at any other time of year, and when the Earth receives the least radiation from it. In practice, however, a 3% difference in the Earth's distance from the Sun is barely noticeable.
Annual changes in our weather, for example between the summer and winter, are caused entirely by the tilt of the Earth's axis of rotation, rather than by any change in its distance from the Sun.
The position of the Sun at the moment of aphelion will be:
|Object||Right Ascension||Declination||Constellation||Angular Size|
The coordinates above are given in J2000.0.
|The sky on 03 July 2017|
9 days old
All times shown in EDT.
The circumstances of this event were computed using the DE405 planetary ephemeris published by the Jet Propulsion Laboratory (JPL).
This event was automatically generated by searching the ephemeris for planetary alignments which are of interest to amateur astronomers, and the text above was generated based on an estimate of your location.