This week we headed out to see Mercury and Saturn close together in the evening twilight, 25 February being a great night to see the two planets.
Mercury and Saturn's proximity continues for the rest of the week and into the weekend, making for a beautiful conjunction of the two planets.
Everyone's talking about the seven-planet parade visible this weekend, 28 February, but of course the planets are already visible in the sky this week.
You don't need to wait until 28 February to see them!
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It's simply that 28 February is one of your best chances to see Mercury, which has just recently emerged into the evening sky and has become the seventh Solar System world visible this month.
This week offers a nice teaser of the planet alignment, as Mercury and Saturn – two of the trickiest planets to see at the moment – are close together in the sky.
Timings will vary depending on where you're located, but roughly 5.50pm is the time to look.
Where and when
You'll need to look in the west-southwest, and you may be thinking that, at this time of the day, that's exactly where the Sun will be setting.
And you'd be right, but Mercury is currently shining at a 'magnitude' of –1.1.
Magnitude is the value astronomers use to describe how bright an object is, and the lower the number, the brighter the object.
In other words, Mercury should be visible, even through the orangey twilight of the evening sky.
Also, the Sun should have set by this time (see our UK sunrise and sunset timings), which is important as you don't want to be looking too close to the Sun without the use of solar filters.
You will need a clear western horizon because both planets will be low down in the sky by the time it gets dark.
The clearer your horizon, the better chance you'll have to see Mercury and Saturn under darkness.
Once Mercury and Saturn have finally set below the horizon and the sky gets properly dark, you'll see the bright planet Venus in roughly the same position.
The sky will be much darker and Venus will be unmistakable: the true 'star' of the show at the moment!
A matter of perspective
Of course, Mercury and Saturn aren't really close together, in terms of their respective locations in the Solar System.
It's just that they appear as such from our perspective on Earth, as we gaze up at the 2D 'dome' we call the night sky.
Two celestial bodies being apparently close together in the night sky is known as a 'conjunction' (more than two and you have a massing!)
In reality, Mercury is about 58 million km (36 million miles) from the Sun, according to NASA, and sits between the Sun and Earth's orbit.
Saturn, on the other hand, is a whopping 1.4 billion km (886 million miles) from the Sun, and is one of the outer planets of the Solar System.
So despite Saturn being about 25 times larger than Mercury, Mercury looks much brighter to the naked eye.
Have a look tonight and see if you can spot Mercury as a twilight beacon low in the west, and whether you can also see Saturn below it.
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