531 days ago
Dominic Ford, Editor
From the Outer Planets feed
Mars will pass close to the Sun in the sky as its orbit carries it around the far side of the solar system from the Earth.
At closest approach, Mars will appear at a separation of only 0°39' from the Sun, making it totally unobservable for several weeks while it is lost in the Sun's glare.
At around the same time, Mars will also be at its most distant from the Earth – receding to a distance of 2.63 AU – since the two planets will lie on opposite sides of the solar system.
If Mars could be observed at this time, it would appear at its smallest and faintest on account of its large distance. It would measure 3.6 arcsec in diameter.
A comparison of the size of Mars as seen at opposition and at solar conjunction.
Over following weeks and months, Mars will re-emerge to the west of the Sun, gradually becoming visible for ever-longer periods in the pre-dawn sky. After around a year, it will reach opposition, when it will be visible for virtually the whole night. A chart of the path of Mars across the sky in 2021 can be found here, and a chart of its rising and setting times here.
The position of Mars at the moment it passes solar conjunction will be:
|Object||Right Ascension||Declination||Constellation||Angular Size|
The coordinates above are given in J2000.0.
The sky on 07 Oct 2021
|The sky on 07 October 2021|
1 day old
All times shown in EDT.
Never attempt to point a pair of binoculars or a telescope at an object close to the Sun. Doing so may result in immediate and permanent blindness.
The circumstances of this event were computed using the DE430 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.
|13 Oct 2020||– Mars at opposition|
|30 Nov 2022||– Mars at perigee|
|08 Dec 2022||– Mars at opposition|
|12 Jan 2025||– Mars at perigee|
© NASA/Hubble Space Telescope