M45 Pleiades cluster

M45 Pleiades cluster

Taken in Northwest Mo, December 9,10-2018 with a Canon 60D 300mm lens, guided using a 60mm guide scope Orion starshoot autoguider, on Celestron avv mount. Expossures, 140 minutes 4 minutes subs lights, 5 flats, 10 darks ISO-1600. Processed using Digital photo pro- to save photos to TIFF, Deep sky stacker, Photoshop cs5 rotated cropped, curves, color balance, selective color, levels, highpass filter

I see a bear paw from underneath.


Great shot.

Gettin ready to break this bad boy out with my college's Astronomy Club this week!

Gettin ready to break this bad boy out with my college's Astronomy Club this week!

I was so confused until I realized that's not a hot water heater.

Why would you need to heat hot water?

Cause it's not hot enough.

Not when it's under enough pressure 👉😎👉

M45 - Pleiades and surrounding dust from very dark skies

M45 - Pleiades and surrounding dust from very dark skies

This my first successful image with a new scope/mount/etc. setup after fighting with guiding and dew images since I got it a year ago. Very happy with the results from nice dark skies! Cross posted from /sub/astrophotography


Telescope: Skywatcher Esprit 100mm, f/5.5, 550mm focal length Mount: Skywatcher NEQ6 Pro Camera: Canon SL2 Guide scope: Solomark F60 60mm, 215mm Focal Length, F/3.6 Guide camera: ZWO ASI120MM QHY Polemaster for polar alignment


Light pollution: Bortle 2 No moon Poor seeing Temperature around 3C Elevation: sea level

Capture Software:

Controlled with EQMod, Stellariam scope astrotorilla for plate solve PHD2 for guiding Captured using Backyard EOS

Capture details:

ISO 800 36 x 5 minute lights 3 hours integration time Camera sensor temp:about 9C


RAW frames prepped in Lightroom. Reduce blacks, set color profile "camera neutral", white balance around 3800, reduce highlights -30. Light noise reduction (mostly color noise). Export to TIF and stack all in DSS PS CS2: Reduce reds and greens with curves to fix color balance a bit RNC Color stretch: stretch 2 versions exported from LR, 1 with heavier noise reduction (stretch power 11, then power 3) and 1 with no noise reduction (single stretch at power 11) LR: Up clarity for non-NR "detail" version PS CS2: Add NR and non-NR versions as layers. "Detail" layer overlayed over NR layer with mask to give the bright parts better detail while keeping the faint stuff low in noise and more smoothed out. PS CS2: Mild curves to add contrast to taste PS CS2: Lower saturation for dimmer areas using layer mask

Thanks! Do you have a link to that discussion (suppose I could google if you don't...). I've used it for maybe 3 images now and it seems good. Better and less noisy than my old T4i, but probably doesn't compare to higher end DSLRs. I did notice noise banding my first image, but dithering completely gets rid of that. I don't have much other reference other than my T4i, but overall a big improvement from that.

No filters? I’ve been trying to get the nebulosity of the Pleiades for some time and it never seems to come through. New to AP though.

No filters. There's a lot of things to consider and it's not an easy target for beginners. Dark skies help, longer exposures help, more stacked exposures helps, and of course lots of practice with image processing to bring out faint details helps. Lots of other things like quality/size of telescope etc. Just keep at it, there's lots to learn.

Orion widefield

Orion widefield

Just blow up already would ya, Betelgeuse?

A lot of atmospheric dust and clouds make for non ideal conditions but it looks alright I think.

Nikon D3300

35mm F/1.8G at F/2.8

8 sec exposure


The star on the right is Alnitak. A binary star system that most likely contains planets. From the surface of Alnitaks planets you'd be able to see the horse head nebula in the night sky with the naked eye.

From the Southern Hemisphere?

Indian stairway to the North Star (part of a giant sun dial)

Indian stairway to the North Star (part of a giant sun dial)

That stairway is not nearly high enough.

Not during the day no duh

This is the Jantar Mantar in Jaipur, Rajasthan; a collection of architectural astronomical instruments completed in 1734.

Jantar Mantar! There's one in New Delhi, too, stumbled on it by accident when visiting some years ago. Apparently there's like five of them overall....

Asteroid Bennu imaged from a distance of 136 km (Enhanced)

Asteroid Bennu imaged from a distance of 136 km (Enhanced)

I wasn't expecting it to look...sparkly almost? I'm not sure what I expected, but this isn't it.

Are there any theories on what is causing this "sparkly" texture?

I would imagine it is because asteroids are mostly piles of rocks and rubble not just one giant rock like we are led to believe by movies. The asteroid also doesn't have strong gravity to pull down the surface and smooth it out. Thus, it's covered with rocks and dust that pile up at different angles. Those rocks are then catching the light at different angles and reflecting it back at the camera. The sparkling you are seeing is just all the various angles of the rubble catching the light in different ways.

This is why it is whiter on the right, because the sun is off to that side and there are more angles that are catching light and reflecting it back at the camera.

this thing is about 400-500 meters in diameter just so you know

It's the Little Prince planet!

Barnard 174 - Dark Nebula in Cepheus

Barnard 174 - Dark Nebula in Cepheus

This is a giant blob of cold gas and dust (like enormous, thousands or millions of solar masses and tens to hundreds of light years across), which is something we can’t see through in visible light, so anything behind it is blocked. It is also so cold that it can’t emit visible life itself, so it is completely black. They are of significant interest in infrared and radio astronomy though and can form stars when they collapse. A normal nebula is hotter, because they typically come from stellar birth or death, which are energetic events. This allows the dust and gas to emit light.

What makes is so dark?

This is dark nebula Barnard 174 in the constellation Cepheus. 1.5 hours just starts to bring out some edge details, so I'll call this a work in progress for now.

E.E. Barnard published a list of dark nebulae in 1919, known as Barnard objects, they number from Barnard 1 to Barnard 370.

Tech Specs: Sky-Watcher Esprit 120mm ED Triplet APO Refractor, Celestron CGEM-DX mount, Canon 6D stock camera, ISO 3200, 88 x 60 second exposures with dark/bias frames, guided using a ZWO ASI290MC and Orion 60mm guide scope. Image date: October 3, 2018. Location: The Dark Side Observatory, Weatherly, PA, USA.

I used to study these before I changed careers, perhaps I can help.

Dark nebula are molecular clouds or complexes, colloquially called GMCs. They have high enough densities that they ‘self shield’ protecting the gas and dust within from heating by nearby stars. This make them opaque in visual wavelengths, but also with no heating source the temperatures (thermal energy) of the gas and dust are very low. At about 10-20 K the gas and dust radiate like a blackbody in the far infrared. Remember the cosmic microwave background radiates like a blackbody at 2.7 K which is detectable in mm wavelengths (aka microwave). I used to observe these with a telescope called Herschel (space telescope) at wavelengths of around 250-500 microns. At these wavelengths the dark nebula become optically thin (transparent). We also use emission of exotic carbon monoxide detectable via radio telescopes, around 1 mm in wavelengths, as a proxy to estimate the amount of hydrogen within these clouds.

Why? Like others have said these GMCs can contain hundreds/thousands of solar masses of hydrogen and with temperatures so low gravity is able to pull the gas into over dense cores or knots. These over densities continue in fall and if not perturbed go on to make stars. These GMCs are quite literally stellar nurseries! I studied these to learn about the physical processes of radiative transfer and the role it plays in the conception and formation of stars.

These complexes are incredibly fascinating and have a lot of really interesting physics happening. Here’s a neat video by the ESA showing how FIR can be used to peak inside the Horsehead nebula in Orion, (hope its ok to link a video).

Newly released NASA Juno spacecraft footage of the "Dolphin" on Jupiter

"So long and thanks for all the fish."

How many Earths is this dolphin

That's what I want to know, just how massively large is this dolphin?

Here you go (static though):

Here you go (static though):

Picture of the Carina Nebula I took a couple of months back in Jamberoo, Australia.

Picture of the Carina Nebula I took a couple of months back in Jamberoo, Australia.

Awesome. I only live 10 minutes away. From Jamberoo, not the Nebula.

Wish me love, a wishing wish to kiss and tell

What's your setup?

We know if you meant the nebula you'd have said "only 10 light-minutes" .

Looking at Western Australia on the map, I envy your dark sky options. I'm on the east coast of the US, which looks like one big gleaming mass in satellite photos. How much light pollution do you get on the east coast of NSW?

The cookies at the Toronto Astronomy on Tap last night were out of this world!

The cookies at the Toronto Astronomy on Tap last night were out of this world!

The picture is of the Pinwheel Galaxy, taken by the Dragonfly Telescope, built by one of the speakers!

Did millions of voices suddenly cry out in terror and were suddenly silenced when you took a bite?

I’d rather eat a Milky Way.

That's definitely not the whirlpool galaxy, looks more like maybe the pinwheel galaxy?

Still cool though

Try one of these subthreads