October 2019 – The Orionids

The next major shower on the calendar is the Orionids, due 21st October – but the advise on observing and imaging the shower is the same for all meteor showers…

Another popular shower with observers and imagers, because of it’s proximity to the magnificent Orion Nebula, this a ZHR (Zenithal Hourly Rate) of around 20.

Source

The source of the Orionids is Halleys Comet. and this very cool image below is interactive so you can drag it around or zoom in to see how the Earcth (blue dot) interacts with the dust trail – click to go to the Meteorshowers.org web page and use the full screen version!

As the comet makes its way around the Sun, it leaves a trail of dust debris and as our Earth makes its orbit, it crosses this trail of dust. As the dust particles collide with our atmosphere, the burn up, causing the streaks we know as meteors or shooting stars. The bigger the grain of dust, the brighter the streak!

How to View

This year, moon rises at approx 21:28 and is waning at 51% illumination. Therefore waiting until after midnight when Orion has properly risen and the radiant is visible is best.

The image below shows where the radiant is

Orionids Radiant
Orionids Radiant

The usual advise is not look directly at the radiant, but further to one side, as this gives a better chance to catch longer streaks.

How many will I see?

Every meteor shower has a ZHR – Zenith Hourly Rate. This is the supposed number you would see under clear dark skies, with the radiant directly overhead at the Zenith. The Orionids is quoted at 20 per hour.

Unfortunately, these numbers are often misquoted by the media and the public are led to believe they will see 100’s of meteors literally raining down on them! Not quite so….

However, the waning moon should not interfere too much, so let’s hope the weather plays ball!

What about using a camera?

Camera’s offer a great way to record the meteor shower! Here are some tips…

  • Mount your camera on a sturdy tripod, and aim it North East
  • Use a wide angle lens and set the aperture as wide as possible (low f/ number)
  • Set the ISO level to around 800 – 1600
  • Set the exposure to 30 seconds
  • Shoot!

You may need to adjust the ISO or exposure time to not wash out the sky or make the camera a little more sensitive to capture the stars.

if you have one, use an intervalometer to program the camera to take repeated exposures – or use a release cable.

Hopefully, you’ll capture some great streaks in your images – and remember to submit them to BAS so we can show them off!

  • Camera on tripod

  • Manual mode

  • Set for 15 seconds

  • Intervalometer set for 15 seconds