This looping animation shows the sky low to the east-southeast horizon as seen from the centre of the British Isles from 23 October to 3 November at approximately 6am BST (or 5am GMT when daylight saving time ends on Sunday, 25 October). The interval between frames is one sidereal day, hence the stars appear fixed and the motion of the planets relative to the constellation Leo becomes clear. Venus reaches greatest westerly elongation from the Sun on the morning of Monday, 26 October — the same day it appears closest to Jupiter (1° separation). Eight days later, on 3 November, the brightest planet passes even closer to Mars (0.7° separation). For scale, the graphic is about 40 degrees wide, or twice the span of an outstretched hand at arm’s length. AN animation by Ade Ashford.In two former posts (see here and here), I drew your attention to the gathering of naked-eye planets in the east before dawn. Up until now, all of the Venus—Jupiter—Mars activity has occurred in the constellation Leo, but on Monday, 2 November magnitude+1.7 Mars crosses the border into Virgo. Hot in pursuit, magnitude -4.3 Venus also crosses the Leo-Virgo border the following morning when the two planets will be closest at just 41 arcminutes apart, or ~0.7 degrees. On 3 November, Mars will have a miniscule disc spanning just 4.3 arcseconds, or one fifth of Venus’ diameter.
However, you don’t need a telescope to follow the changing configuration of these three fascinating planets on successive days as it will be obvious to the naked eye or in binoculars. And if you have a low-power, wide-angle binocular, you can encompass all three in the same field of view throughout the period in question — if weather permits, naturally!
Inside the magazine
You can find out more about this month’s planetary peregrinations in the November edition of Astronomy Now in addition to a full guide to the night sky.
If the excitement of the Juno spacecraft’s arrival at Jupiter has prompted you to seek out the solar system’s largest planet, then the 5-day-old cresent Moon acts as a convenient celestial guide during the evening of Saturday, 9 July when it makes a close pass of the gas giant. Here’s our guide to where and when to see this beautiful celestial pairing.
The numerous whirlwinds covering Jupiter are caused by upward gas flows originating deep within the giant planet. This is the conclusion reached by scientists at the University of Alberta (Canada) and the Max Planck Institute for Solar Research (MPS) in Germany after extensive computer simulations. Their models also explain why the Jovian whirlwinds’ direction of rotation is opposite to storms on Earth.
Planetary scientists have discovered pieces of opal in a meteorite found in Antarctica, a result that demonstrates that meteorites delivered water ice to asteroids early in the history of the solar system. Opal, familiar on Earth as a precious stone used in jewellery, is made up of silica (the major component of sand) with up to 30 percent water in its structure.