Dave Payne's Astrophotography & Interpretation – APRealSpace

Explore Dave Payne's Astrophotography, showcasing stunning images and insights into astronomy, star formation, galaxies, and more.

Photography

The Hidden Galaxy – Now you see it

IC342/Caldwell 5 – The Hidden Galaxy in LHaRGB Planewave CDK 12.5in; AP 1100GTO AE; QHY600M, – Baader Cmos Opt Broadband and 6.5nm Ha FiltersL: (50 x 180s, Bin 1, Gain 100); H: (29 x 720s Bin 1, Gain 100); R,G,B: (25,23,22 x 210s, Bin 1, Gain 100)Total integration time = 12.4 hrs (Feb 10-12, 2025) Maple Bay, BC, Canada For full resolution, downloadable image, visit my gallery at Victoria RASC Zenfolio or Astobin The Hidden Galaxy gets its name from its position in the sky, near the Milky Way and partly obscured by our galaxy’s dust. If not for the dust, IC342 would be visible with the naked eye and occupy about the same size as the moon. In reality

Its Supersonic! – But it’s complicated

The massive explosion of a supernova sends material (and light) outwards in all direction, at velocities greater than the speed of sound. The speed of sound is another way of saying the speed that pressure or density waves can travel or disperse through the medium that it is moving through. The particles ejected by the supernova are moving so fast and so much momentum that they don’t disperse but act like a moving wall of material, bulldozing and sweeping up any additional material in its path. Along the way, the particles that make up this moving wall, or shock front involves a lot of friction between particles so that it heats up to extreme temperature (million of degrees) and the wall emits light that we see as the remnants or remains of a supernova.
This wall, known as a shock-front, eventually runs out of momentum due to is expanding spherical geometry and sharing of momentum, but remains visible to our cameras long afterwards, until it fades through cooling. The patterns of emitted light are both beautiful and distinctive from other subsonic flow patterns, and these patterns enable us to identify these objects as supernova remnants. or leftovers from the supernova explosion.

The Whirlpool Galaxy (M51) – In for Questioning

The M51 Galaxy or “The Whirlpool Galaxy” definitely strikes an awsome pose, with its two apparent “centres”, and multiple star fuzzies emanating from its extremes. I decided to get all Sherlock Holmesy on it in my desire to figure out what was going on. Yes it is two glalaxies interacting, but what is the nature of this interaction. What happened to its bottom arm? – it looks like it was bitten off. The upper arm looks more intact, but also exhibiting Halpha starburst too. Is the bottom of the galaxy connected to the top with stars circling the left hand side? Can infrared light help us? Can it potentially reveal something? I recommend reading more to find out.

The Cave Nebula and Hydrogen’s Journey

One cannot understand the creation of stars from molecular hydrogen clouds any more than one can understand the weather here on earth without reference to thermodynamics. The weather is largely driven by water in gaseous (vapour), liquid (rain, clouds) and solid (snow, ice and ice crystals) forms. Knowing the pressures and temperatures at which these physical phase states occur is fundamental for both water in its role of creating weather, and for hydrogen in its role of creating both stars and the galaxy itself. Every atom and molecule of hydrogen must undergo and piecewise continuous journey through its phase/space – there is no leaping allowed, and the conditions must exist somewhere in a system for phase transitions to occur.
In our description of galaxies, we discuss the atomic and molecular phase states of hydrogen, but here we illustrate and explain the rest of the phase/state journey that hydrogen, at least at the nucleus of a star, must undergo to enable star formation. This is a journey from molecular gas all the way to becoming a hot, molten, liquid metal.

Collapse of a Molecular Cloud in 3 waves

The standard textbooks indicate that the start or conception of a new star formation is the collapse of a molecular cloud. But my background in thermodynamics, heat/mass transfer and fluid mechanics leaves this superficial explanation ungratifying (at least to me?). This pervasive theory has already be debunked in my description of spiral galactic structure, but what should replace it? What would cause a molecular cloud or part of one to “collapse”. I have presented here, three variations of the same view of the Bernard 169 (the loopy one on the right), and Bernard 174 (shaped like a foot on the far left) – both molecular clouds in the process of “collapsing”, or as I would rather put it – condensing – towards star conception. Both B169 and 174 are dark nebulae that emit no light of their own, but rather block light from the background and reflect any starlight from stars in their proximity. There are indications, even in this dark nebula, of new star formation – can you spot them?

Winding Problem Solved – Galactic Spiral Structure (Part 4)

If the galaxy were a disk, gravity would act toward the centre of the galaxy, centrifugal forces in the opposite direction, and viscous drag perpendicular to both. In a galactic spiral structure, this is not the case as components of all three forces act along and perpendicular to the spiral arms. This gives spiral shapes the ability to avoid the arms winding upon each other, and even orbits spots that aren’t at the galactic centre. Force balances on the spiral arms, show how this comes together in this detailed analysis. The post is long, but I think insightful and revealing. Coupled with the thermodynamics of hydrogen – even does away for the need for dark matter.

Narrowband Light & Filters – A Quick Overview

Using the fascinating and recently discovered Squid Nebula (Ou4) as an example, I discuss the use of narrowband filters to image emission nebula. To emit light at specific narrowbands, the right element, degree of stimulation (UV light), and even density must be present. It makes for beautiful images and reveals a lot of structure in the targets.