What you need
Binoculars
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THE coming week is a great time to look for planets. A new moon on 28 October means no moonlight and, with the exception of Neptune, every planet is visible at some point in the coming days. Even distant Uranus, which at 8 pm GMT on 27 October will be a mere 2.8 billion kilometres away.
Venus is the easiest to find, with an apparent magnitude of -4.6. In the magnitude scale, objects with lower numbers are brighter. It is close to the sun, so you can find Venus in the east before sunrise or in the west after sunset. On 29 October, you should see it below the crescent moon after sunset.
The following day at the same time, Mercury (magnitude -2.0) will be very close to Venus. We will be returning to Mercury in a few weeks’ time, however, when it is at its furthest point from the sun.
The other planets are harder to find, so it helps to know how they differ from stars. The first is that stars twinkle more. Twinkling happens because light refracts in different directions as it passes through Earth’s atmosphere. Stars are points of light, so they seem to twinkle more than the light spread over the disc of a planet.
Another giveaway is position. Stars stay fixed relative to one another, but planets move and can appear in a different place from one night to the next. The ancient Greeks called them wandering stars, planetes asteres, hence the name planet.
That wandering isn’t random. Because they orbit in a similar plane as Earth, from our point of view planets all follow the path of the sun, roughly speaking.
Jupiter is fairly bright, glowing blue-white at -2.7 magnitude. It will be near the moon on Thursday, setting in the west at about 8 pm local time. If you have binoculars, try to spot the tiny pinpricks of its moons spread in a straight line on either side.
²Ñ²¹°ù²õ’s magnitude varies. At the moment, it is fairly dim at around 1.8. It has a reddish glow and this month appears in the east/south-east before sunrise.
Saturn (magnitude -0.5) is pale yellow and this month will set about 2 hours later than Jupiter in the southern part of the sky. The way Saturn’s poles are tilted right now means it is a good time to see its rings if you have a telescope.
Even though Uranus is close, it is very dim: magnitude 5.7. If you did the light pollution test from week three, you should know if it is possible to see it from your area. On 28 October, it reaches opposition, meaning it is on the opposite side of Earth from the sun, so in theory, it is visible all night. Uranus rises in the east as the sun sets, following the sun’s path and reaching the highest point in the sky around midnight.
If you are uncertain about what you can see, try a stargazing app to confirm whether you were right.
To download a printable version of the page click here.
For next week
You don’t need anything
Next in the series
2 Find the North Star and Southern Cross
3 Test your area’s light pollution
4 Identify the craters of the moon
5 Orion and Sirius: how to star-hop
6 Planet spotting: Mars, Mercury and Uranus
7 Taurus and the zodiacal constellations Star-hop from Orion into the zodiac
Stargazing at home online
Projects will be posted online each week at Email: maker@newscientist.com
