I think that I may have gotten a bit carried away during a period of paper-writing avoidance. I made this toy embalming kit for my partner (who's an embalmer) and I've learned more than I ever thought that I would about aneurysm needles, grooved directors, and Frigid Rigid. So much fun! :-)

I'm in Yellowknife this week, and sky was lovely last night. Wow. Just, wow.

Just a few more images from Elginfield Observatory. Taken with my full-spectrum Canon 7D and a 720nm filter.

As a follow-up to my last post about Space.com getting the details wrong, here's the actual press release describing our work properly...

news.westernu.ca/2025/06/came...

Although they got the details wrong, this is us :-)

www.space.com/astronomy/ea...

The image that is shown is for a single camera stack over a 24h period. Thousands of satellites (mostly LEO) are observed passing through the field-of-view, highlighting just how busy our night sky is becoming.

To answer your question, though, when we see strong calcium lines in a meteor spectrum, it's typically coming from the calcium H and K lines which are very short wavelength, making them look quite blue/purple. These are different lines than you see when doing a flame test.

And some are sodium-rich, while others are iron-poor. Also, the oxygen/nitrogen is from the atmosphere, and we seen it, with increasing strength, at speeds > 25 km/s. There are many different compositions that we see, when observing meteor spectra, and it's not nearly as simple as the image suggest.

It's worth noting that most meteors will be composed of many different elements. So, you will typically see iron lines along with sodium and magnesium. Some are mostly iron, and you will then see just the iron 'multiplets' that are towards the blue/green end of the spectrum.

I decided to take a break from work today, step outside, and take a few infrared (720 nm and beyond...) pictures around the observatory. I always find observatory domes to be photogenic subjects that look good even in daylight.

While taking pictures of the lunar eclipse the other night, I thought, 'Wow, nice clouds!' while looking at the camera screen. A few shots later, I realized that they weren't clouds at all. Just an artifact of not using a filter on a full-spectrum camera. A rookie mistake, but still kind of pretty.

In a recent open-access article published in PASP the meteor-tracking spectrograph for the Canadian Automated Meteor Network (CAMO-S) is described. iopscience.iop.org/article/10.1....