How Comet Neowise helped me find a bug
Comet Neowise over London
Comets are spectacular but its rare for one to visit us that’s bright enough to be seen with the naked eye. But in the northern hemisphere, comet Neowise is currently visible low in the northern sky in the early hours of the morning.
I’d seen a lot of impressive photos on Twitter and was determined to see it to. So I put its (Declination, Right ascension) in a software tool I’ve been working on and worked out there it would be in the sky at 03:40 Saturday morning and set my alarm for twenty minutes earlier.
I might as well as just have stayed asleep, for it all went wrong. First up, by 3:30 it was beginning to get light, and combined with London’s light pollution it was really hard to see even the brightest stars. Then the location chosen (Battersea Bridge) was too well lit, which ruined my night vision. But the worse thing was the calculations were wrong and the comet wasn’t where expected: my software had a bug in it.
What was annoying was that the sky had actually been amazing and if I’d woken earlier I’d have caught both the comet and some lovely noctilucent clouds, and as you know I do love a good NLC show.
But the forecast for this morning was also looking good so I set the alarm for 2 am and headed out for the local park, suitably dark, and with good view across the Thames at the northern horizon.
And yes, I spotted the comet! I took the zoomed in photo above, and also the one below which shows its reflection in the still river Thames at what must have been around 02:30:
Comet Neowise reflecting in the River Thames in London
Magical!
After visiting us, comet Neowise is heading out into the dark of deep space, and won’t be returning for another 6,800 years. If you want to glimpse the visitor in our skies, it will be visible in the early morning for another week or so and then late evening. But there’s always the risk it might break up, so its not guaranteed to stick around.
Top tips are:
Get a pair of binoculars or camera with long lens: it is visible to the naked eye but more detail is available using some form of magnification
Check the weather for astrophotography - I use the ClearOutside web site and app
Check the position of the comet in the sky - I found it using TheSkyLive web site
Find a location where the sky is dark and you can see low down towards the north. This might mean going to a park or finding a hill
Set your alarm: I found the best hour was 2 am - 3 am: by 3:30 the sky was already getting light.
Good luck!
Tonight I’m not sure I’ll be staying up: I need a good night’s sleep to see if I can find that bug in my software on Monday!
Comet Neowise over trees on the Thames riverbank in London
Update: bug found! Wrong function being called to convert vectors from J2000.0 reference to local frame
