Perseids 2023

perseids wide field 8/12-13/23
north lower right
radiant at perseus right side

having repeatedly tried and failed to catch any meteor images in my back yard over the past few years, i elected to go out to the Orange County Astronomers dark sky site in anza to image this year's perseids with near new moon conditions.  

Burn line from recent fires near OCA site
Dave Kodama's cameras ready to go

OCA regular heungsoo choi in action

perseid buzzing OCA's anza house 8/12/23 23:06

while i've seen meteor showers from dark skies, including Yosemite and Yellowstone parks, this was in many ways the best.  others have had more frequent bursts, but these were typically faint white lines.  this night's show was filled with bright orange streaks.  by no means a meteor storm--the bright one's trickled in, but there were more than i've ever seen.  over the course of 7 hours, even with passing clouds, my camera captured 21 bright meteors.  they were rainbow colored in the camera, changing from red to green as they heated in the atmosphere, despite an orange visual appearance.  

perseid 8/13/23 00:50 local time

there were many faint meteor candidates, but  they were difficult to confirm due to abundant satellite traffic.  i only included bright streaks that were colored and directed towards the radiant in perseus. 

I used a fisheye lens to capture a wide swathe of sky, nearly horizon to horizon:

milky way center, perseid top left
N-north star, A-andromeda galaxy, P-constellation perseus
northern horizon bottom left
southern horizon top right
SUV bottom right :(
8/13/23 00:50 local time 

sadly, there were clouds passing through many of the images, making a composite difficult.

Star trails 8/12-13/23
polaris, north star lower left
anza house bottom left corner
my annoying SUV side light bottom right corner
southern horizon top right corner
(click for larger size)

typical recommendations are to just sit back and look up to view meteors. 

meteor shower observing accessory

the distribution in this capture was skewed towards the radiant in perseus on the horizon.  however, many of those were foreshortened with longer streaks on the opposite horizon.  

perseid distribution map 8/12-13/23
(click for larger size)

the best time to view meteors is between midnight and dawn.  i've also read 4 AM.  

a steady stream with clusters at 2AM and 3AM

imaging details:
5/12-13/23 10 PM to 5 AM
Anza, CA
passing clouds
nikon D850
Sigma 15mm F/2.8 EX DG fisheye
20 sec, iso 1600

missed the first hour as i set the camera delay to 20 minutes instead of 20 seconds between shots :(

the last meteor was caught at 5 AM, after astronomical dawn.  i saw several bright meteors as i was setting up, so i should have started imaging much sooner despite the "after midnight" recommendations.  

Venus and Mercury

took another crack and venus and mercury.  unfortunately seeing was not great...

Venus 4/16/23 02:43 UTC
IR pass 850nm

Mercury 4/16/23 02:33 UTC
IR pass 850nm

i decided image venus during the day (venus is bright enough to see in broad daylight, it's just really hard to find) for 2 reasons: 

-all other things being equal, the seeing should be better with the planet at higher altitude 

-i was hoping to capture motion of venusian clouds by imaging over a long period of time.  

sadly it was a total bust. imaging runs over 20 minutes captured no cloud detail whatsoever (until earthly clouds obscured my view).  perhaps a hint of something towards the upper half as venus got lower in the sky:

Venus 4/17/23 00:36 UTC
UV

Venus 4/17/23 00:05 UTC
IR pass 850 nm

at a recent meeting of the OC astronomers, Chris Go (who admittedly doesn't image venus) suggested that sunlight saturates the daylight sky with UV ruining the detection of clouds.  or perhaps it was just a clear day on venus ;)

I have captured cloud detail in the past with this set up at twilight:

venus UV clouds

Image details:
camera ZWO ASI 290MM 
filters: ZWO IR pass 850, Baader U-filter bw 320-380nm
celestron 11" Edge HD
East Bluff, CA

4/16/23
mediocre seeing
02:43 UTC
2x barlow
IR pass 850 filter:

venus
FPS (avg.)=215
Shutter=0.746ms
Gain=351 (58%)
Frames captured=69635

mercury
02:33 UTC
2x barlow
FPS (avg.)=116
Shutter=3.281ms
Gain=436 (72%)
Frames captured=12765

4/17/23
Venus 
no barlow as UV is faint
mediocre seeing

UV filter:
00:36 UTC
FPS (avg.)=217
Shutter=2.055ms
Gain=351 (58%)
Frames captured=39233 

IR filter:
00:05 UTC
FPS (avg.)=42 ?!
Shutter=0.191ms
Gain=351 (58%)
Frames captured=12865

another falcon

dragged the kids out to the front yard to see a falcon launch with potential for a sunlit plume against the night sky. having been dragged out the night before for a launch that was delayed an hour and then aborted at T-5 seconds, their patience was wearing thin.   

after seeing a thin rocket trail rise above the trees followed by a faint orange plume, my son went back inside...  

only to miss the sunlit plume light up as the rocket passed out of the earth's shadow:

rocket and the owl tree

Falcon-9 7/19/23
note detached fairings and 1st stage trailing in the plume. 

Falcon-9 7/19/23
note detached fairings and 1st stage trailing in the plume

local color

Image details:

wide view

Samsung galaxy S22 ultra

close ups

nikon D850

F-S DX NIKKOR 55-300mm f/4.5-5.6G ED VR

ISO 1600

7/19/23 Newport Beach, CA

night owls

 decided to try my astrophotography skills on a noisy pair in a tree across the street:

Great Horned Owl

Note the big black eyes indicating a night shot, in contrast to the golden irises seen in daylight images.  The owls were not visible to the eye so it took a bit of work to aim and focus.  

Here's the noisy couple in the "owl tree" across the street where they hoot away to the chagrin of my neighbor who is less enamored with them due to their noise and their abundant droppings.    

Great Horned Owls

Oh, and here's M97 the owl nebula for comparison:

image details:

birds:

tall view
Samsung galaxy S22 ultra
f1.8 1/4 s 23mm ISO 2500
1/7/23 eastbluff, CA
close up
nikon D850
F-S DX NIKKOR 55-300mm f/4.5-5.6G ED VR
f/5 @130 mm 1/2 sec ISO 1600
11/10/22 eastbluff, CA

Owl nebula:
Celestron Nexstar8GPS @f/6.3(1300mm), SX AO-.2 sec exposures, CS 10 nm HA/baader oiii 8.5 nm, H9.
4/12-16/08 los alamitos, CA
HFD 3-4 arcsec
bortle white skies
21x20 min Oiii, 20x20 min Ha

maybe time for a reshoot with NII

a rocket for the 4th (falcon 9 6/22-23/23)

 there was a late night falcon 9 launch on 6/22

it being a weekday in the midst of a loooong run of of clouds, i chose to give at quick try from my front yard rather than an optimal viewing site.  so with the spaceX stream running on my phone i went out and looked northwest towards vandenberg.  i'd seen the orange glow of a night falcon launch in the past, so i thought i might catch it.

12:19AM "Lift off"...nothing

T+1:16 "Max Q"...nothing

T+2:35-2:38 Main Engine Cut Off, "stage separation"...nothing

I begin packing up just as a cone of light grazed the owl tree:

Falcon 9

i was able to catch a few closer shots as it faded. difficult catching a moving target in the dark:

Image details:
in viewing the spacex stream, it looks like they were clouded out locally which might be why i couldn't see the rocket on initial lift off.

Eastbluff, CA
6/23/23 ~12:25 AM

wide view
Samsung galaxy 22S ultra
f1.8 1/4 s 23mm ISO 4000
10/27/22 Newport Beach, CA

nikon D850
F-S DX NIKKOR 55-300mm f/4.5-5.6G ED VR
f/4.5 @55 mm 1/80 sec ISO 102,400!
used absurdly high iso to capture the faint moving object
this resulted in very noisy images which had to be denoised after dark subtraction

More mars: northern polar hood, bonus jupiter

 After imaging the mars occultation (which occurred at low altitude), I waited a few hours for mars to reach maximum elevation and increased the magnification.

A layer of clouds, referred to as the northern polar hood, covers the north pole in these images.  Surface structure is more evident in the IR images which cut through cloud cover. 

Mars 12/8/22  07:26.1 UTC

probably snowing on the north pole.  

also got some bonus time on jupiter:

Jupiter 2022-12-08 04:36.3 UTC

Jupiter 2022-12-08 04:29.9-04:42.6 UTC

Image details:

average seeing

Mars 12/8/22  07:26.1 UTC

Jupiter 12/8/2204:29.9-04:42.6

eastbluff, CA

celestron 11" Edge HD

ZWO ASI 290MC (one shot color camera)

2x powermate

baader IR/UV block filter

ZWO IR pass 850 nm for IR images

Jupiter 

Image reduced by 50% due to poor seeing

10x90 sec

FPS (avg.)=42

Shutter=2.581ms

Gain=351 (58%)

Histogramm=41%

Mars

RGB 6x120 sec

FPS (avg.)=145

Shutter=1.000ms

Gain=351 (58%)

Histogramm=46%

IR 2x120 sec

FPS (avg.)=147

Shutter=5.000ms

Gain=351 (58%)

Histogramm=33%

mars eclipse (occultation) 12/7/22 aka 12/8/22 ~02:27 UTC

 On December 7th, both mars and the moon were in opposition--directly opposite the earth.  for the moon that means a full moon.  for mars it means the planet is roughly closest to the earth in it's orbit, so visually much larger and brighter than other times during the year.  since the planets in our solar system generally orbit in the same plane...the moon "eclipsed" (occulted) mars this year at opposition--an excellent photo opportunity.  

Mars emerging from lunar occultation
12/8/22 ~03:34 UTC
stacked composite

A different perspective:

Mars has risen
occultation egress
stacked composite

Same image, full scale crop:

occultation egress
stacked composite
full scale crop

Occultation start, 4x speed:

I used sky safari, to preview the location of mars at egress then, eyeballing the craters, navigated my narrow high power field to where I thought mars would appear.  Miraculously it appeared dead center in the field.  

Occultation end 4x speed:

Kudo's to the sky safari app

Imaging commentary:

The occultation occurred with the moon rising low in the east (6:30 PM local), so I had to move from my usual imaging location.  Unable to set up the night before, I had to bolt from work like Fred Flintstone at the whistle and set up from scratch.  polar aligned sighting thru the saddle at polaris, then 1 object align on mars.  did not have time to tune the ADC. Whatever settings I had last time were probably better than nothing.  

Used a lower gain and max histogram to improve the dynamic range.  

Processing was a bear.  Stacking software (autostakkert) could not handle my occasional field adjustments, so I wound up having to edit the video into smaller clips with PIPP, virtual dub, and photoshop, then process separately.  

The first two images are composites combining a stacked mars image, a stacked moon image, and a single frame.  

Image details:

12/8/22  ~02:27-03:34 UTC

eastbluff, CA

celestron 11" Edge HD

ZWO ASI 290MC (one shot color camera)

ZWO ADC

baader IR/UV block filter

12 fps, 1.844 ms, 152 gain, 100% histogram

isolated mars after egress

56 fps .924 ms, 251 gain (only 41%, should have been higher)

This was my second time using the celestron CGX which has some nice ergonomic features for rapid set up

Mars is here, 11/26/22. filter tricks--IR filter with RGB camera

 Mars is here.

The seeing wasn't great this session, so i imaged without a barlow.  I wanted to test out an infrared filter with a color camera which worked perfectly (see details below).

Mars 11/26/22 8:51 UTC
RGB left, IR 850 pass center, IR-RGB composite right

as i was breaking down the gear, i noticed that the stars were no longer twinkling ;) 
broke out the barlow and got less sleep than planned:

Mars 11/26/22 9:26 UTC
single 120 sec capture

Why an infrared (IR) filter works with a color camera:

the color filters in many color cameras pass infrared light.

(which is why you should use an IR blocking filter)

The ZWO 290 MC passes the IR from an 850 nm IR pass filter equally through all color filters.

as a result, you can get a uniform full resolution monochrome IR image when using an IR filter with a color camera.  

just be sure to set the color balance for all filters to neutral (see below).  

Image details:
11/26/22  08:34-09:26 UTC
celestron 11" Edge HD

first set
ZWO ASI 290MC (one shot color camera)
baader IR/UV block filter for RGB images
400 fps, .191 ms, 351 gain, 40% histogram, 120 sec x 4
ZWO IR pass 850 nm for IR images
set green and blue gain to .5 in fire capture for IR
400 fps, .855 ms, 351 gain, 35% histogram, 120 sec x 3

second image
ZWO ASI 290MC (one shot color camera)
baader IR/UV block filter
televue 2x barlow
152 fps, 2.132 ms, gain 291?, histogram 49%, 120 sec
single 120 sec capture

firecapture, autostakkert 5% stacked, winjupos, maxim, photoshop
elevation ~80 degrees
Eastbluff
Southern California

for IR-RGB blend IR was used as red channel and 30% luminance, color rebalanced on white pole structure.  

ref:

IR filter with ZWO camera

https://astronomy-imaging-camera.com/product/1-25-ir-850nm-pass-filter

"just don’t forget to keep the WB_R and WB_B to 50 (no White Balance applied)."

fire capture screen shots:

click for full size

click for full size

another try at mercury

detail on mercury is still on my wish list.  unfortunately, the goto on my failing mount is not up to mid day imaging.  so i gave it a shot as it set near the horizon.  seeing was pretty bad at low altitude.  a low pass IR filter pulled out the planet, but no evidence of detail. 

Mercury 5/4/22 02:56 UTC

processing notes:

for reasons which escape me, my stacking software (autostakkert) was completely unable to distinguish bright, but totally distorted frames (which were the majority) from a well defined crescent.  as i result i had to manually select approximately 200 frames out of 8,651.  a process made even more tedious by a windows update blowing all my work about half way done.  needless to say, this one sat on the hard drive for a while.  finally made it thru all the frames, but alas, didn't get anything more than a crescent, no detail.  to be expected i guess with such poor seeing.  

prior attempts

image details:

camera ZWO ASI 290mm IR pass filter 850
celestron 11" Edge HD, no barlow
8651 frames @75 fps 6.085 ms gain 351

upsampled ~2x
5/4/22 02:56 UTC (5/3/22 ~8 pm local)
East Bluff, CA
poor seeing, IR filter helped

more craters: petavius and langrenus

cruising along the 3 day old crescent moon from mare crisium leads to this pair of craters with prominent central peaks and terraced walls:

craters patavius and langrenus
3 day old moon 5/4/22 03:04 UTC

to the left is Patavius, notable for a 
-wide double rim
-complex central mountains 1.7 km from the floor and a 
-deep fracture from the peaks to the rim of the crater. 

Patavius

views of petavius are reportedly very sensitive to contrast:  

"The shadows retreat with surprising speed and for the rest of the lunation, until just after full Moon, Petavius is identifiable as a white oval. Its grandeur then reappears briefly before the whole region is engulfed by the lunar night."(Sir Patrick Moore)

to the right is Langrenus notable for a 

-20 km wide terraced rim 3 km high on the eastern side

-1 km central peak

Langrenus

there is a ray system on the crater floor which appears when the sun is directly overhead (not evident in this image).  

In 1645, Michel Florent van Langren was the first person to draw a lunar map while giving names to many of the features. This is the only one of his named features that has retained his original designation (wikipedia). 

Among his contributions were attempts to determine longitude...He believed he could improve the accuracy of longitude determination, particularly at sea, by observing peaks and craters of the Moon as they appear and disappear, hence the map (wikipedia).

between the two craters lies Vendelinus, an ancient crater lacking a central peak who's rounded walls and floor are covered with newer impact craters.  

Vendelinus

image details:

camera ZWO ASI 290mm IR pass filter 850

celestron 11" Edge HD, no barlow

3865 frames @59 fps 6.928 ms gain 351

5/4/22 ~3 AM UTC (5/3/22 8 pm local)

East Bluff, CA

poor seeing, IR filter helped

refs:

https://en.wikipedia.org/wiki/Petavius_(crater)

https://www.skyatnightmagazine.com/astrophotography/moon/petavius-crater/

https://en.wikipedia.org/wiki/Langrenus_(crater)

https://en.wikipedia.org/wiki/Michael_van_Langren#Contributions

https://en.wikipedia.org/wiki/Vendelinus_(crater)

sea of crisis, a lunar mare

a lunar mare (latin for sea) is a large smooth dark region on the surface of our moon.  early astronomers thought they resembled seas on the earth, hence the name.  
mare crisium caught my eye, emerging from lunar night on a 3 day old waxing crescent moon:

Mare Crisium, Sea of Crisis
5/4/2022 03:01 UTC

mare crisium is a realtively small lunar mare on the northeast quadrant of the moon.  it can be easily seen on the full moon:

mare crisium is the dark circle top
in front of the "bunny rabbit's ears"

it's the first mare to appear after the new moon, forming the "eye" of the moon's crescent:

mare crisium, the eye of the crescent upper left

lunar maria are thought to have been formed by huge asteroid impacts on the young moon which had a thin crust over hot magma.  the huge asteroids created large craters and cracked the crust.  liquid magma then flowed in--filling the craters and cooling to a smooth surface.  so at one point, they sort of were seas.  the high concentration of iron in the magma darkens the surface.  

refs:

https://lovethenightsky.com/how-did-lunar-maria-form/

https://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/lola-20100702-crisium.html

https://www.glyphweb.com/esky/surface/marecrisium.html

image details:

camera ZWO ASI 290mm IR pass filter 850

celestron 11" Edge HD, no barlow

880 frames @16 fps 6.928 ms gain 351

5/4/22 ~3 AM UTC (5/3/22 8 pm local)

East Bluff, CA

poor seeing, IR filter helped

full disk

11/27/12

FS 102, SX H9 (probably)

crescent

5/26/2006

FS 102, SX H9 (probably)

falcon-9 launch 10/27/22

tonight's falcon-9 launch exceeded expectations despite a relatively bright sky:

Image details:

nikon D850

F-S DX NIKKOR 55-300mm f/4.5-5.6G ED VR

first image f/5 @55 mm 1/80 sec ISO 1600

close ups:

 1/250 sec f/5.6 @300 mm ISO 1600 

wide views 

Samsung galaxy S22 ultra

f2.2 1/30 s 2.2 mm ISO 640

f1.8 1/10s 6.4mm ISO 1000

10/27/22 Newport Beach, CA

Jupiter and Saturn on a warm summer night

had a rare warm summer night with clear skies and decent seeing.  unfortunately my mount is on the fritz, so i was unable to get out the big scope, but had a nice session with my C8 cruising the summer sky, then finished off imaging saturn and jupiter which just happen to have the GRS in view:

Jupiter 9/4/22 07:00 UTC
click image for large size

It's been a while since i've imaged saturn, the ring tilt is really decreasing.  better view of the globe, north pole difficult:

Saturn 9/4/22 07:15 UTC

Imaging Details: 
celestron nexstar 8 gps, zwo adc, baader IR/UV block filter, zwo asi 290 MC
90 sec captures

jupiter 
FPS (avg.)=66
Shutter=1.000ms
Gain=351 (58%)

saturn
FPS (avg.)=70
Shutter=14.24ms
Gain=351 (58%)

Eastbluff, CA 9/3/2022

color boosted lunar eclipse

some models predict all the colors of the rainbow can be detected at the edges of an eclipsed moon.  here's an image at the end of the total eclipse with the color saturation boosted to bring out the color:

5/15/22 lunar eclipse
color saturation boosted

A discussion on the cloudy nights forum covers it.  There are 3 phenomenon leading to color on the eclipsed moon:

1. preferential scattering of shorter wavelength light as it passes through the earth's atmosphere (red sunset effect).

2. atmospheric refraction of light (prism effect).

3. preferential absorption of red light by ozone in the upper atmosphere (blue filter effect).  

i'm only seeing red going to blue, but none of the rest of the rainbow in this image. 

if you look below the blue section, there's a hint of teal (the blue level is equal to green, but never exceeded by it).

Here's an over-the-top article on the topic:
High-resolution spectroscopy and spectropolarimetry of the totallunar eclipse January 2019

image details:
5/15/22 
near pacific ridge trail head overlooking el moro canyon in crystal cove park (southern california)
nikon D850
poor transparency 
F-S DX NIKKOR 55-300mm f/4.5-5.6G ED VR @ 300 mm F/5.6