What to See in The Autumn Sky

Autumn is a superb time for stargazing and viewing some of the planets furthest from Earth – the gas giants as they are known. There is the opportunity to see meteor showers and rare alignments. Local night sky expert Geoffrey Lindop gives us some background, the best viewing dates and photo tips for making the most of the autumn skies.

Saturn: The Ringed Giant in Autumn Skies

Saturn used to be called ‘the planet with the rings’ but various space probes have also discovered rings around Jupiter, Uranus and Neptune as well – albeit less spectacular. You need a telescope to observe the rings, so why not book a place in one of the public observatories in the South of Scotland such as Moffat, Whithorn, or just across the border at Kielder. With plenty of accommodation nearby, you can choose from cosy B&Bs and family-friendly cottages for your stargazing holiday.

Rising in the east just after sunset during August, observers can spot Saturn most of the night. It remains in the constellation of Pisces, the fishes, although its position in the sky will change from hour to hour and day to day. On September 21 at 6:10am BST, it will be at its closest to Earth for this year. However, at that specific time, it will be low in the west. The best time to observe will be around midnight on days around that date, when it will be at its highest in the south. This year, the rings tilt at a narrow angle of 2 degrees, so they are not as spectacular as they could be, but they are well worth seeing. Especially on September 21, when the planet will be in an equivalent position to the Full Moon and hence no shadow, no gibbous phase. The tiny particles that compose the rings are, in effect, mini full moons. Consequently, the rings will be slightly brighter than normal.

Lunar Events: Eclipses and Occultations

At a quarter of a million miles, the Moon is the closest celestial object to Earth. The telescopes at the public observatories in the region can see objects as small as 5 miles, and even binoculars can see fairly small craters. Bring one along on your trip to observe the Moon by night, and the local wildlife by day.

Astronomers don’t enjoy observing the Moon when it is full. There are no shadows and therefore no contrast with the crater walls, making it difficult to observe the full detail of its landscapes. However, many will watch it on September 7/8, when the Earth’s shadow will totally eclipse it. The next lunar eclipse on March 2/3 next year will not be visible in the UK, so don’t miss this one.

We can even see the Moon move against the background of stars. On September 12, the Moon passes in front of the Pleiades star cluster. You need to be at one of the public observatories unless you have a small astronomical telescope. Concentrate on the dark side of the Moon – the one in the shadow of lunar night. Suddenly, the stars of the Pleiades blink into vision, and you can watch them as the Moon moves further away from them. The first star to appear will be 17 Tauri at 22:05 BST, followed at 22:31 by 23 Tauri. Alcyone, the brightest star in the Pleiades, will appear at 23:24. Observers may see other stars depending on the telescope’s size. The Moon clears the Pleiades at 01:19 the next day. If you missed the phenomenon, astronomers call it a lunar occultation, there will be another opportunity on October 10, but conditions are not as favourable being close to sunrise.

The camera on your mobile phone is all that is required to capture the Moon close to other celestial objects. Having one of the stunning historic sites in the South of Scotland in the foreground makes for a splendid picture.

Planetary Alignments & Constellations

This season offers some striking opportunities to see planetary alignments. The Moon, planets and bright stars appear close together, events that can often be spotted with the naked eye or binoculars. They are especially fantastic for keen astrophotographers: Capture these stunning displays with the backdrop of local landscapes.

On September 8 the Moon, almost full, rises just after sunset very close to Saturn. There will be a nice display on September 11 with Saturn in the west, the Moon, Uranus, Jupiter and Venus in the east all equidistant from each other. Unfortunately, Uranus is too faint to be seen without binoculars.

In the early hours of October 13/14, the Moon and Jupiter will be in Gemini, just below Castor and Pollux, the two brightest stars in that constellation. If you miss it, try again on November 9th or December 7th, when they will be in a similar position.

Pollux, the brightest star in Gemini and situated to the left of Castor, the second brightest star in that constellation, is about three times further away than Procyon. Its light takes 34 years to reach us. Astronomers classify it as a red giant, the closest such star to Earth. Its mass is almost twice that of the Sun. The planet Thestias orbits it, but scientists do not consider it capable of supporting life. Castor is slightly fainter than Pollux, despite being not one but six stars much further away than Pollux. We are seeing Castor not as it is today, but as it was 49 years ago!

Procyon is the eighth brightest star in the sky and located in the constellation of Canis Minor, the Little Dog. It is one of our nearest celestial neighbours with light taking only 11.46 years to reach us. It is not one star but a pair that orbit each other every forty years. The two stars are separated by a distance slightly less than that of Uranus from the Sun.

In the early hours of October 13/14, the Moon and Jupiter will be in Gemini, just below Castor and Pollux, the two brightest stars in that constellation. If you miss it, try again on November 9 or December, when they will be similarly placed.

Then, on November 13 the Moon will be close the Regulus, the brightest star in Leo.

Castor, Pollux and Procyon are again photogenic on the morning of September 13 when Jupiter will be between the three of them. Jupiter is the largest planet with a mass greater than all the other planets combined. Ninety-seven moons orbit the giant planet. Galileo discovered the four largest moons when he focused his telescope on them in 1610. If you don’t have a telescope, visit one of the public observatories where you will also see the Great Red Spot on Jupiter – a storm larger than the Earth that has raged since the time of Galileo and probably forever.

Mars spends most of the next few months on the other side of the Sun, and Venus will disappear from our skies in the middle of October.

Mercury, the closest planet to the Sun, is always difficult to spot, but will be at its furthest from the Sun just after sunset on October 29, and just before sunrise on December 7th. You should be able to see the planet, weather permitting, on the days either side of those two dates. It is a planet whose surface looks much like the Moon, but only spacecraft can reveal that. Even the telescopes at our observatories will only show it as a small disc.

Autumn Meteor Showers & a Comet

A comet has been described as a dirty snowball. Dust and grit left over from the formation of the Solar System is mixed with a high proportion of water-ice. When comets fly past the Sun, they eject material. The dust particles that form their tails end up orbiting the Sun, and when the Earth passes through that debris, it forms a shooting star, also known as a meteor. A fascinating display worth staying up for.

The Draconid Meteor Shower is due to appear on October 8/9 but bright moonlight will spoil the display. Better wait until a few weeks later around October 21/22 when the Orionid Meteor Shower coincides with New Moon. This debris from Halley’s Comet, which seems to originate from the constellation of Orion, produces trains of very swift meteors. 

November is a particularly good month for seeing meteor showers. Debris from Comet Tempel-Tuttle creates bright trains of shooting stars, originating in the constellation of the Lion on most nights of the month. The Leonids are expected to peak on November 17, when 15 meteors per hour are likely to be seen.

One of the best showers is the Geminids, which will streak across our sky on December 13-14, maybe a few days before. These are debris from an asteroid rather than a comet, and they tend to be larger and therefore brighter.

If you want to know more about the phenomena above our heads – make for the Dark Space Planetarium in Kirkcudbright, Scotland’s Artists Town. Here a hands-on display brings the subject to life for all ages and regular talks and showcases in their dome offer a close-up view of our solar system.

You can learn more with our Top Tips for stargazing and be sure to visit our Dark Skies section for all the information and inspiration you need to plan your next visit.

Geoffrey has written a guide to the night sky to assist visitors in the South of Scotland, available to purchase at various locations across the South of Scotland or directly from the publisher.

We are grateful to Geoffrey for producing a regular guide to the skies above us, so you can check out what there is to see throughout every season. Make sure to look up on a clear night and look out for the glittering display of our truly dark skies.