Alpha Monocerotids: Don’t get your hopes up about the rare ‘Unicorn’ meteor storm

Two meteor scientists, Peter Jenniskens and Esko Lyytinen, predicts an outburst by the alpha Monocerotids meteor stream on 21 or 22 November, depending on where you are in the world.

If you’re not an early riser, you’ll have to set your alarm.

alpha Monocerotid outburst: Here’s what you need to know

What are the alpha Monocerotids meteor streams?

According to the Bronberg Weather Station in Pretoria, the alpha Monocerotids meteor streams are “groups of meteoroids originating from dust grains ejected from an unknown comet.”

When the Earth passes through the alpha Monocerotids meteor stream and dust particles, we could witness what is referred to as ‘shooting stars,’ or a meteor shower.

Will it be visible from South Africa?

It will, but there are several factors involved that might spoil the show for us. Those in the northern hemisphere will have prime seats (but not those on the Pacific Coast). It will be 22:50 when the outburst peak for them.

It will be 6:50 in South Africa on Friday morning when Earth passes through the stream, but it would be best to keep an eye starting at midnight.

Do note that optimal viewing conditions aren’t on our side. It will also be mostly cloudy over large parts of South Africa. But that’s not even the worst of it.

NASA meteoroid forecaster is skeptical

Even Nasa refers to the meteor event as a possible upcoming space event, and not a definite one, despite all the hype generated about it in the media. Bill Cooke, Lead at the NASA Meteoroid Environment Office, writes:

“The media is currently broadcasting the prediction of an outburst of the alpha Monocerotid meteor shower on the night of November 21. […] But as the media inquiries increased, I began to wonder if all the attention is justified.”

Cooke explains that, as a meteor shower forecaster, he had to take a “more detailed look” and verify the calculations for himself. He came to the conclusion that if there was an outburst, it “won’t be as impressive as many think.”

Cooke goes on to explain that according to Jenniskens and Lyytinen calculations, the Earth passed through the centre of the alpha Monocerotid meteor stream in 1925 and 1935. However, there is no proof that this actually happened.

An unidentified comet

Cooke does say that it’s a “reasonable assumption if these outbursts were more intense than the last one in 1995”.

Jenniskens and Lyytinen also claim that the parent comet responsible for the meteor shower takes about 500 years to orbit the Sun. Cooke adds:

“If this is right, then we should pass very close to the center of the meteor stream this year, missing it by a scant 15 000 miles. That’s just a tad closer than we got back in 1995, when the observed zenithal hourly rate was about 400 per hour.”

That said, the intensity of the outburst is also dependent on the size of the comet’s orbit. He explains that if the comet is smaller or larger than initially calculated, Earth will pass through the meteoroid stream as predicted, but there’ll be no fireworks in the night sky.

Cooke also reminds us that the mysterious parent comet has not been discovered yet, so there is no way to check the veracity of Jenniskens and Lyytinen’s predictions. But don’t give up hope altogether thought. Cooke says:

“A good reason to step outside Thursday night, [Friday morning, for South Africans] because the cool thing is that if an outburst does occur, we will have a pretty good idea of the orbit of this comet – not from observing the comet with telescopes, but by counting its debris as they burn up in our atmosphere.”

How to view the (possible) meteor outburst

Hey, if there’s still a chance of seeing this rare outburst, we’re all for it. If it’s not too cloudy, find a dark spot outside and look east north-east towards the constellation Monoceros, also known as the Unicorn constellation.

The best time to view the alpha Monocerotids is from around midnight to dawn. If everything works out in our favour, you’d be able to see about four streaks an hour; or even more during the peak.

Also read – Leonid Meteor Shower 2019: What you need to know [live stream]