Messier 8 and the ultra-young Hourglass Nebula

[Martin Meredith]

Here's a live LRGB shot of the Lagoon Nebula from a few days ago taken with my 8" f4 reflector and Lodestar X2 mono guide camera plus Baader filters (just under 6 minutes -- details on the shot). This was a rare night of marvellous seeing. [Ignore the temperature reading -- it was nearer 20C; and I'm guessing that the SQM was around 19.5 with the moon still up]

 

The Lagoon Nebula (M8) has a little of everything. Apart from the great flowing mass of the nebula itself, it houses several of Barnard's dark nebulae, an open cluster (NGC 6530), a nebulosity within the nebula (the Hourglass), as well as 9 Sgr, one of the most luminous stars known (actually, a binary with a period of 9 years); the luminosity is 100s of thousands times larger than our own sun. 9 Sgr and its neighbour are mainly responsible for lighting up the nebula.

Some of these components are indicated on the single 15s sub below (yes, this is bright, even at under 20 degrees of altitude). 

The hourglass is the pink bowtie near the centre of the upper part of the cluster; rotated by 90 degrees the hourglass shape becomes clearer.

This cluster is being ionised by a multiple star 'Trapezium-like' system known as Herschel 36 (the bright object to the right of the hourglass) which consists of a minimum of 10 stars in a 4 arc second radius (= 2 of my pixels).  The Hourglass itself is around 15" x 30". This is well-described in the paper [1] whose Figure 1 shows what the region looks like in near-infrared. 

I read somewhere (but can't lay my hands on it now) that this group of stars is exceedingly young -- 10 thousand years only. Amazing to think that they would have started on their journey at the time we humans were starting to think about building our first cities.

Now I need to wait for a few more years to match this seeing....

cheers

Martin

[1] https://arxiv.org/pdf/astro-ph/0506552.pdf

[Bill S]

Martin

Remarkable detail in those shots.

Best regards

[JeremyS]

That’s super @Martin Meredith.

Do you use Starlight Live with the Lodestar?

[Mike JW]

Fascinating. I was not aware of the hour glass nebula. Those super clear nights are to be savoured.

Mike

[callump]

Fantastic image Martin - perhaps you can send some clear skies this way...

Callum

[Martin Meredith]

19 hours ago, JeremyS said:

That’s super @Martin Meredith.

Do you use Starlight Live with the Lodestar?

Thanks Jeremy. I've been using StarlightLive (SLL) for most of my EEA life since it was released in 2014 I think, but more recently I've been using Jocular, some EEA software I'm developing. Originally I used SLL to 'feed' subs Ito Jocular ie as a capture engine, but in the most recent version of Jocular I've implemented native support for the Lodestar, so it all happens from Jocular. I've also managed to get the SX electronic filter wheel controlled natively, so the whole LRGB capture can be done in a single button press, which means I can concentrate on observing the image building up. SLL was the only way up to now (I think) of doing this kind of multispectral capture in a live setting -- definitely a pioneering piece of software. 

Martin

[Martin Meredith]

Thanks, Bill, Mike & Callum. Believe me, these nights are rare here and I made the mistake of not extending the session far into the early hours because I didn't want to be like a kid in sweetshop, rather thinking of saving some for other nights. A bad decision.... In general August has been quite poor here too -- maybe 4 or 5 clear nights.