How to see tonight’s twin meteor shower in the UK

Want to spot a meteor shower tonight? You can have two: both the Delta Aquariids and the Alpha Capricornids are both set to peak at the end of July 2021.

This means you can expect to see up to 30 meteors shoot across the night sky – with up to five of these being spectacular slow-moving yellow fireballs.

But how exactly can you see them? When? And what exactly actually is a meteor in the first place? Glad you asked: we’ve answered all these celestial quandaries (and much more) below.

Plus, if you’re looking for more stargazing tips, be sure to check out our astronomy for beginners guide, and our full Moon UK and meteor shower calendars.

When can you see the Alpha Capricornid and Delta Aquariid meteor showers 2021 in the UK?

The Southern Delta Aquariids and the Alpha Capricornids meteor showers both peak between 29 July and 30 July 2021, with shooting stars most visible between 2am and 4am.

While you stand the best chance of spotting a meteor during this period, the Alpha Capricornids will last until 14 August, while the Delta Aquariids will last until 24 August. During this time, each will produce a small number of meteors.

The largest meteor shower of the year, the Perseids is also set to peak on 12 August 2021.

How can you see the twin meteor showers 2021?

Leave your telescope and binoculars inside: the best way to spot a meteor is with the naked eye. That’s because although meteors of each shower originate from certain areas in the night sky (known as radiants), they won’t be visible in those exact spots.

In case you’re wondering, Alpha Capricornid shooting stars will originate at a point near the constellation Capricornus. Meanwhile, the Delta Aquariid shower has a radiant close to the constellation Aquarius. If you want to easily find these points in the night sky, we recommend using a stargazing app such as SkyView Lite (free on Android and Apple devices).

Read More:

• How do we predict meteor shower intensity?
• Can you hear a meteor?
• How do spacecraft avoid asteroids and meteoroids?

The later you stay up on the night of 29 July and 30 July, the more meteors you’ll see. That’s because these radiants will appear higher in the sky (and fewer shooting stars will be hidden by the horizon).

Letting your eyes adjust to the darkness for at least 20 minutes will be key before observing a shower. If you can, keep away from city nights and avoid looking at your phone – it will scupper your night-time vision! 

How many meteors will I be able to see?

During its peak, the Delta Aquariids have a zenithal hourly rate of 25. This means – as you may have guessed – you can spot 25 meteors an hour in good conditions (a reasonably strong number, compared to 2021’s other showers).

Meanwhile, the Alpha Capricornids only have a zenithal hourly rate of five. However, some of its shooting stars may be spectacular slow-moving yellow fireballs.

What actually is a meteor shower?

A meteor shower is caused by space debris that lights up the night sky as they burn up in Earth’s atmosphere.

Don’t worry: the debris (normally dust from a comet or asteroid) that falls to Earth is tiny – generally only the size of a grain of sand. Despite being so small, they can create bright streaks in the sky by travelling at extremely high speeds (up to 66km/s – several times faster than a speeding bullet).

It’s currently not clear where the debris of the Delta Aquariid shower originates. However, some have theorised the shower is caused by fragments of the comet 96P Machholz, which orbits the Sun every five years.

On the other hand, astronomers have identified the parent object of the Alpha Capricornids: a comet known as 169/NEAT, likely to be several kilometres in diameter.

Read more about meteors, comets and asteroids:

• How can we tell that a meteorite has come from a particular planet?
• Comets and asteroids: Five things you (probably) didn’t know about them
• The sky is falling: should you be worried about asteroids and comets?

How can I take a picture of a meteor shower?

Before attempting to photograph a meteor, be warned: it’s not the easiest thing to do on your phone. However, it is possible.

Ideally, you want to turn your flash off and set your exposure for as long as possible. Apple users can use the app NightCap for extended exposures (available on the Applestore, £2.99), whereas Android users can download the Camera FV-5 Lite app (Google Play, free). With a long exposure, you need to keep your phone extremely steady – a tripod is a must if you don’t want blurry photos.

 And if you have a digital camera to play with? “For meteor showers, you need to open the aperture as wide as possible – a small ‘/f’ number such as f/3.5,” says Dr Darren Baskill, physics and astronomy lecturer at the University of Sussex.

“The ISO should also be reasonably high, such as 1,600, 2,000 or 4,000 (but this will depend on the camera). As for exposure, try two seconds under light-polluted skies, but much longer (over 15 seconds) under dark skies,” he adds.

Remember, with such a lengthy shutter speed, a tripod (or at least a solid garden fence to lean the camera on) is advised.

What’s the difference between meteors, comets and asteroids?

Although often used interchangeably, there are key differences:

• Meteors are the bits of rock and dusk that break away from comets and asteroids. A meteorite is what falls through the Earth’s atmosphere.
• Asteroids are masses of rock that orbit the Sun in the asteroid belt between Mars and Jupiter.
• Comets, like asteroids, orbit the Sun. However, they’re made of ice and dust rather than rock.

About our expert, Dr Darren Baskill

Dr Baskill is an outreach officer and lecturer in the department of physics and astronomy at the University of Sussex. He previously lectured at the Royal Observatory Greenwich, where he also initiated the annual Astronomy Photographer of the Year competition. 

You can follow him on Twitter.

from... sciencefocus.com