witch's broom and the veil

  here's the witch's broom nebula:

and the ghoul:

both are part of the veil supernova complex

haunting tale:
7,000 years ago, a massive star burned out, collapsed, and then exploded, creating a supernova.
several thousand years later, prehistoric man looked up in the sky and saw a bright light visible during the day
that lasted for weeks. 
(this was about the time the monolith arrived)

200 years ago, with the aid of the telescope, man discovered
the expanding cloud of gas created by the supernova.
it is very large (3 degrees, or 36x bigger than the full moon) and very faint.
the witch's broom (above) is one edge of the expanding cloud
the other side is shown below at a smaller scale
you can almost see a bow wave ahead of it:


here's the whole thing (click for full size):

Veil nebula

this is a 4 panel mosaic with a total of 32 hours of exposure time
taken over the course of 2 months

~700,000 years from now the expanding shock wave will hit our planet
what will happen to life was we know it?

the bright side (from NASA):
"Although only about one star per century in our Galaxy will end its life in this spectacular way, these explosions are responsible for making all chemical elements heavier than iron, as well as being the main producers of oxygen in the universe. Elements such as copper, mercury, gold, and lead are forged in these violent events. The expanding shells of supernova remnants mix with other clouds in the Milky Way and become the raw material for new generations of stars and planets. The chemical elements that constitute Earth, and indeed those of which we ourselves are made, were formed deep inside ancient stars and distributed by supernova explosions in nebulae like the one we see here".

P.S. recent data indicates heavy elements being formed by neutron star mergers in addition to super novae (confirmed spectroscopically) , something new under the sun. 

On that note:
happy halloween

Jupiter Methane filter

after catching a glimpse of jupiter's great red spot starting to unfurl, i picked up a methane filter (which enhances the great red spot...and looks cool ) to see if i could better detect the activity.  it's a bit hard to wrap your head around what a methane filter does.  the short version is that high altitude clouds on jupiter (including the great red spot) appear very bright with a methane filter (detailed discussion below).

in the methane filter image below, there is high signal at the great red spot (a giant storm high up in the atmosphere), at a high altitude equatorial belt, and at polar clouds.  in contrast the signal is extremely low on the east and west sides where the light passes tangentially through extremely thick layers of methane: 

Jupiter 7/21/2019 05:54 UTC RGB left, Methane center, Methane(as red)-GB right

The swirls around the GRS (center) and red trail (right) might be related to the GRS unfurling: 

Jupiter 6/29/19 06:17 UTC, Europa upper left

Jupiter 6/27/19 05:23 UTC 

here's my take on methane filters.  methane (CH4 for you organic chemistry fans) is present throughout the atmosphere of the gas giants in our solar system.  it generally absorbs light in the red end of the spectrum.  the methane filter only passess light in a very narrow range around a specific *absorption* band of methane in the infrared (no green house gas comments please).  since the gas giants are full of methane, they actually appear very dark with a methane filter (in contrast, the jovian moons are extremely bright relative to jupiter with this filter as they have no methane).  so when sunlight hits jupiter and reflects back to us, the light travels through less methane where high altitude clouds reflect the light back (so less light is absorbed).  the higher the clouds, the brighter the signal (factor of 2 here since the signal is absorbed on the way in and out). 

here's a sequence of jovian moon europa (which has no methane atmosphere) passing across the surface of jupiter.  reflecting all the methane signal, europa is extremely bright in the methane images, in contrast to the dark disk where methane absorbs the light: 


conversely, europa is barely detectable in the visible light images as jupiter's surface shines so brightly: 


Imaging details:

camera ZWO ASI 290MM with ZWO RGB filters

Baader methane 889 nm 8 nm bandwidth

celestron 11" Edge HD
East Bluff, CA

90 second captures, 2x binning for methane
no barlow

7/21/19
2 captures each filter
upsampled 2x for processing, then reduced to 60%
6/29/19
4 captures each filter, except 12 for methane
6/27/19
2 captures each filter

gain 351, exposure ~0.6-1.0 ms, 30% histogram, ~280 fps

methane exposure 111-240 ms, 3-8 fps

hetch hetchy night and day, yosemite

Here are shots of the hetch hetchy reservoir in the northwestern part of yosemite national park

Hetch Hetchy, night and day, Yosemite National Park

Here's a slightly brighter view of the falls and reservoir with the landscape lit by the setting moon.   the diagonal stripe mid frame is the milky way, slightly obscured by passing clouds on the horizon. 

among other things seen in this northern view are Cassiopeia, mid milky way,  and the andromeda galaxy to its right (see later images with annotations)

Here are a few hours of star trails:

the red leaves in the foreground were not turning in July, but briefly illuminated by my red flashlight while imaging. 

here's a video of the rising milky way, with some passing clouds as the moon set, followed by a reverse version with star trails, ending with the setting moon illuminating the hills. 

The dam kicked up quite a bit of spray.  i spent an embarrassing amount of time trying to capture a moonbow as the moon set.  the next morning the rising sun produced a beautiful rainbow at the same site--letting me know i was shooting from the wrong side of the spray.  DOH! 

Though there were no major meteor showers, we saw at least 4 an hour in the dark yosemite skies.  Only caught one with the camera:

Here's sagittarius and the milky way along with a few wandering planets shot from the dam

A bit to the right, here's scorpius with bright jupiter.

straight up we saw the summer triangle with the cygnus the swan mid milky way

In August, we back packed from Tuolumne Meadows to Grant lake (again in Yosemite). 
Here's a cell phone capture of my favorite constellation, Cassiopeia, the giant W, along with the milky way and the andromeda galaxy (same part of the sky as the earlier images). 

Cassiopeia from Tuolumne Meadows

here are sagittarius, saturn and the milky way rising at grant lake.

a final moon set thru haze at grant lake:

imaging details (for astrophotography nerds only):
many technical problems with these outings
the wide field images were plagued by my laptop switching to power saver mode several times grrr...
I missed focus on basically all of the DSLR images, hence the small scale.  the cell phone images showed some promise, but the phone's exposure time is limited to 10 seconds. on the plus side, it allows captures in raw mode, allowing for dark subtraction.
perhaps i'll try this again with a modern DSLR and dedicated wide field lens.

The Moment cell phone lens attachment gives a wider field of view and is faster.
though there was little chromatic aberration, there were severe star distortions at the edges requiring cropping :(

Hetch Hetchy wide field (night)
ZWO ASI 290MC
stock fisheye lens
Shutter=20.0s
Gain=351 (58%)
20 second exposures continuously from
11:43 PM 7/7/19 to 1 AM 7/8/19 AM PDT
Hetch Hetchy, Yosemite National Park, California

(day)
Samsung Galaxy Note 9
FL 4.3 mm f/2.4

Moon
Nikon D60
stock lens (18-55) @15 mm f/3.5
30 s
ISO 1600

Rainbow

Nikon D60
stock lens (18-55) @18 mm f/8
1/250 s
ISO 100

Meteor, Sagittarius, Scorpius, Cygnus
Nikon D60
stock lens (18-55) @18 mm f/3.5
30 s
cygnus 88x30 sec ISO 400
scorpius 8x30 sec ISO 1600
saggitarius 5x 30s ISO 1600
even with dark subtraction, there was significant amp glow especially on the cygnus shot, hence the desaturation.
sky watcher star adventurer mount (tracking stars)

cell phone Cassiopeia and Sagittarius
Samsung Galaxy Note 9 with moment Wide 18mm Lens (Magnification Ratio - .63X)
FL 4.3 f/ .945 ?
30x10 s
ISO 800