Night sky highlights - March 2018

The best of astronomy this month: Look for Venus around sunset throughout March.

By Dhara Patel, Astronomy Education Officer

(Details given are for London and may vary for other parts of the UK).

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Top three things to see this month

1st Mar - Look to the waxing gibbous moon beside the bright star Regulus.

7th - 11th Mar - See the Moon pass by Jupiter, Antares, Mars and Saturn.

18th Mar - Catch the very thin waxing crescent moon close to Mercury and Venus.

Look Up! Podcast

As well as taking you through what to see in the night sky each month, Royal Observatory Greenwich astronomers pick their favourite astro news story. For March, they're discussing what's been revealed about the intersteallar asteroid - Oumuamua, in the 4 months since its discovery and the possible detection of rogue exoplanets in a distant galaxy. Have a listen below and vote for your favourite news story on our Twitter poll during the first week of the month. 

1 March

Moon and Regulus

To begin the month, you’ll find the waxing gibbous moon only a degree apart from the bright star Regulus in the constellation of Leo.  That’s about the width of your little finger held out at arm’s length. Regulus is actually a 4-star system but the stars are so close together that they look like a single point. The Moon and Regulus will rise above the eastern horizon by sunset and fall below the western skyline around sunrise so they should be visible all night.

By the following night the Moon will have reached its full moon phase – the first of the two full moons this month.

7-11 March

Moon, Jupiter, Antares, Mars and Saturn

Alike to last month you can once again watch the Moon pass by Jupiter, the star Antares, Mars and Saturn during the predawn hours from the 7th to the 11th March. Look towards the south – the planets look like bright stars. Jupiter will be the brightest of the planets but Mars is getting brighter – it’s brighter now compared to its nemesis in the sky, Antares, which translates as anti-Mars or rival of Mars. Mars is starting to get brighter because later this year the Earth will pass between Mars and the Sun. Astronomers call this an opposition. Due to Mars’ close proximity to the Earth at this time it will appear very bright – outshining Jupiter in fact! 

18 March

Moon, Mercury and Venus

Throughout the month you’ll be able to spot the brightest planet Venus in the western sky as the Sun starts to set and just after. Mercury will be nearby too but it’s much harder to spot. However Mercury will reach greatest eastern elongation on the 15th (that’s when from our viewpoint Mercury is at its furthest point from the Sun) so it will be easier to find then. By the 18th, the very thin waxing crescent moon will join this pair. 

Interesting facts about Venus

20 March

After some quite chilly winter nights, the Vernal equinox on 20th March marks the start of astronomical spring. The equinoxes mark when the Sun crosses the celestial equator. For those of us in the northern hemisphere, it’s when the Sun passes from south to north across the celestial equator. At this time we have approximately equal hours of daylight and darkness and for the coming months, our hours of daylight will get longer and the Sun will appear higher in the sky each day at local noon.

When does Spring start?

25 March

Just a few days later we’ll be marking the start of British summer time so don’t forget to change your clocks on Sunday 25th March. Our clocks will go forward an hour at 1:00 am on Sunday morning so we’ll be losing an hour of sleep but this tradition was started about a century ago to make use of the longer daylight hours. It allows us an extra hour of daylight in the evening that would normally be missed in the morning as most of us would be asleep then.

When do the clocks go forward?

31 March

full moon

On the last day of the month the Moon will once again reach its full moon phase. According to the more modern definition a blue moon is the second full moon that occurs in a single calendar month. But this actually comes from a misunderstanding of the traditional definition which states that a blue moon is the third out of four full moons that occur in an astronomical season. In any case, blue moons are relatively rare events and it’s where the saying 'once in a blue moon' arises. Although the moon can sometimes appear a bit bluer, blue moons aren’t actually blue in colour. So although the Moon won’t look any different, the full moon is still a great sight to observe through the night. 

The Moon's phases this month

Crystal Brilliance © Tommy Richardsen
Crystal Brilliance © Tommy Richardsen
  • 2 Mar - full moon (00:51am)
  • 9 Mar - last quarter moon (11:20am)
  • 17 Mar - new moon (1:12pm)
  • 24 Mar - first quarter moon (3:35pm)
  • 31 Mar - full moon (12:37pm)

See the other amazing photographs from the 2017 Insight Astronomy Photographer of the Year competition in our free exhibition like Crystal Brilliance by Tommy Richardsen which was one of out shortlisted images for Our Moon category in 2016.

Stargazing tips

  • When looking at faint objects such as stars, nebulae, the Milky Way and other galaxies it is important to allow your eyes to adapt to the dark – so that you achieve night vision.
  • Allow 15 minutes for your eyes to become sensitive in the dark and remember not to look at your mobile phone or any other bright device when stargazing.
  • If you are using a star app on your phone switch on the red night vision mode.
  • Need a stargazing telescope or decent binoculars? Check out our range of high-quality observing equipment recommended by Royal Observatory astronomers:

See our range of observing equipment

Share your astronomy pictures

Congratulations to Craig Harvey for his stunning image of the supermoon. He shared this image on our astrophotography Facebook page and we chose it for March's banner image.

If you want to be in with a chance to showcase your astrophotography skills on the banner of next month's night sky blog, share your photos via our Royal Observatory Astrophotography Facebook group

You can also connect with us on Twitter @ROGAstronomers

Insight Astronomy Photographer of the Year

Peak to Peak © Joel Gillespie
Peak to Peak © Joel Gillespie

Come and see the amazing entries and winner to the world's biggest astrophotography competition in our free exhibition at the Royal Observatory.

See the 2017 Insight Astronomy Photographer of the Year competition

If you've been inspired by the image from last year's competition then get involved this year. Enter your astronomy images for the chance to win cash prizes and have your work featured in our 2018 exhibition. This year's competition closes midday 9 March 2018.

Our 2018 Insight Astronomy Photographer of the Year competition is now open

See more of the night sky

Come on an amazing tour of this month's night sky in our Sky Tonight live planetarium show.

See the Sky Tonight planetarium show

Central image: © Craig Harvey 

Resources for teachers and students

The Royal Observatory learning team have also created:

  • Free animated videos that answer the biggest questions in astronomy and free resources to go alongside them.

You can find them here

EM spectrum from ROG video 'What is light?'
EM spectrum from ROG video 'What is light?'
  • A whole host of podcasts featuring interviews with real space scientists, astronauts and active researchers working in UK Universities.

You can listen to these here

  • During the winter months we hold Think Space Lectures - we invite active researchers in the field of physics and astronomy to come and talk about the new research they are doing. School tickets are free.

You can find more information here

Prof Raman Prinja, Astrophysicist
Prof Raman Prinja, Astrophysicist