Try increasing gamma if dark sections aren't distinguished

Try increasing gamma if dark sections aren't distinguished

Monday, July 16, 2018

conjunction junction venus and luna

conjunction: two astronomical objects coming together.

disclaimer: i'm not much on terrestrial photography and my DSLR battery died as i focused, so cell phone, point and shoot and lots of photoshop. enough excuses...

artsy composition thru trees (see the earthshine?):

California sky, with palm tree, pink clouds, airplane and low smog:

OK back to astrophotography

venus and moon during twilight (which or course didn't fit in the same telescopic field) photoshopped together:

Ultra Venus:

Imaging details:

venus and moon
7/15/18 03:18 UTC
Celestron 11 edge HD
Camera=ZWO ASI290MM
venus with
Baader U filter: 350nm, bandwidth 60nm (320-380nm)

7/15/18 8:40-9:20 PM pacific
wide view
cell phone, Droid Turbo
tree view
Sony DSC-RX100M3
f/2.8, iso 6400 26 mm

Southern California

Sunday, July 15, 2018


While you may have read some of the hype surrounding the most favorable Mars viewing since the 2003 opposition (which helped inspire my interest in astronomy), there's a less encouraging story surrounding Mars recently.  
Recall Mars is the only planet in the solar system who's surface detail can be seen telescopically, and that Mars is only in a favorable position for viewing from earth every 2 years (20 months).  More on Mars in my 2013 blog entry
Unfortunately, what started as a small dust storm on a portion of the surface has evolved into one of the largest dust storms in recorded history, completely obscuring surface detail for the last few weeks.  While planetologists find this fascinating, it's a bummer for amateur astronomers, as all that can be seen is a featureless orange disk.  

Here's an image of mars from 2005.  The snaky white structure just right of center is a dust storm:
Mars 10/19/05 08:00 UTC
Here's my first image of mars this year.  The entire surface is obscured by dust:
Mars 7/14/18 08:00 UTC
An infrared image cuts thru some of the storm, showing a bit better contrast:
Mars 7/14/18 08:00 UTC, infrared

Consider the fate of a manned Mars mission dependent on solar power during a month long planet-wide storm...Potato!

Some nice before and after images can be seen in this sky & telescope article

Nevertheless, the storm seems to be lessening, so there may be more to see during opposition on 7/23/18. 

Image details:
10/19/05 08:00 UTC
nexstar 8 gps, 2.5x powermate
toucam pro ii
1/500 exposure 3000 frames
Los Alamitos, CA

7/14/18 08:00 UTC
celestron 11" Edge HD
televue 2x barlow
zwo RGB filters, Baader IR pass "685" nm
90 second captures each filter, 200 FPS
gain 361, exposure ~1 ms (3 ms blue), 30% histogram
elevation 30 degrees
Southern California

Saturday, July 14, 2018

Ultra Venus

Venus is covered by a thick layer of clouds which shines brightly, making it the brightest planet in the sky.  See prior Venus overview.  Visually it appears to be a featureless white disk which goes thru phases like the moon.  However, UltraViolet light shows rapidly moving clouds, thought to be composed of sulfuric acid and aerosols(wikipedia):  

Venus Visible light 7/3/2018 ~3:30 UTC

Venus Ultraviolet colorized 7/3/2018 ~3:30 UTC

Venus Ultraviolet grey scale 7/3/2018 ~3:30 UTC

Venus Ultraviolet 7/2/2018 ~3:30 UT
Venus Ultraviolet 7/14/2018 3:35 UT
Venus Ultraviolet colorized  7/14/2018 3:35 UT

No detail in this one:
Venus Ultraviolet 7/4/2018 ~3:30 UT

Couldn't pick up any detail in IR:
Venus Infrared 7/3/2018 ~3:30 UTC

Imaging details:
imaging in UV was complicated by light loss and poor focusing of UV light by glass elements in the image train, increased UV susceptibility to atmospheric distortion, and turbulent air near sunset when Venus is visible.
typical capture
Celestron 11 edge HD
Camera=ZWO ASI290MM
Frames captured=109386
FPS (avg.)=272
Gain=361 (60%)
Baader U filter: 350nm, bandwidth 60nm (320-380nm)
Baader IR pass "685" nm

Southern California

Sunday, July 1, 2018

summer saturnalia

Still celebrating a summer Saturnalia.  I've had a run of the best seeing locally in several years.  It's a great time for planetary observing with Venus at sunset, Jupiter transiting at a gentlemanly 9 pm, Saturn near opposition around midnight, and then a blazing Mars rising in the east, approaching  opposition later this month.  

Here are more images from my recent capture of the Saturn's polar hexagon.  Infrared, up-sampling the video by a factor of 3.  
Saturn with north polar hexagon, infrared image 6/26/18 7:45 UTC

Here's a north polar projection, showing the hexagon:

The hexagon was not visible in my RGB image (click on image for full size):
Saturn RGB 6/26/18 7:45 UTC

Here, I've added infrared as luminance to bring out the hexagon in the RGB image.  You can also see that the banding on the disk is much more prominent in infrared (click on image for full size).
Saturn with north polar hexagon, RGB with IR luminance  6/26/18 7:45 UTC

Lastly, here's an annotated wider field:

The cause of the hexagon is still not clear.  One theory is that a hexagon forms where there is a steep variation in the speed and viscosity of atmospheric winds.  The hexagon was blue when it was discovered by the voyager probe in 1981, but has changed to a gold color.  More information on the hexagon at wikipedia.  

The north polar hexagon can only be imaged from earth when Saturn's north pole is tilted towards us.  It was maximally tilted towards us last year and will be tilting away for the next 15 years, when the south pole will be facing us, then begin tilting back.  So you can see the source of my urgency in capturing it.  

image details
celestron 11" Edge HD
zwo RGB filters, Baader IR pass "685" nm
processed in PIPP
upsampled 3x in autostakkert
sharpened in registax
combined in winjupos
6/26/18  07:45 UT
Southern California

Tuesday, June 26, 2018

Eureka, The Hex!

neared Saturnian nirvana last night 
think i got a legit shot of the hexagon
if you look closely at the top dark ring, you can see the corners:
Saturn Infrared

image details
celestron 11" Edge HD
Baader IR pass "685" nm
3 minute capture
FPS (avg.)=269
Gain=351 (58%)
33% histogram
upsampled 2x in autostakkert
sharpened in registax
6/26/18  07:45 UT

Southern California

Friday, June 15, 2018

Jellyfish, Supernova Remnant IC 443

The Jellyfish nebula is a large supernova remnant in the constellation Gemini. Hydrogen (Ha-red) and Oxygen (OIII-blue):
IC 443 in Ha and OIII
click for larger size
Here's a bright starless Ha version in jellyfish orientation with the "body" up top and "tendrils" reaching down:
Jellyfish Nebula Ha

The OIII signal is much more faint than the Ha, it was boosted in the above image to show the OIII detail. 

A darker version with the blue OIII barely visible

Blink comparing starless Ha and OIII versions:
IC 443 in hydrogen and oxygen
Note that in OIII it looks much more like an expanding ring of gas resulting from an explosion than Ha. 

Here are brighter versions of Ha:
IC 443 Ha
and OIII:
The nebula is 50 arc minutes, larger than a full moon.

Now some of you crab nebula fans are probably asking where is the neutron star remnant? Is there a pulsar, pulsar wind?  The box lower left, is the location of a presumed pulsar--a spinning neutron star left over from the star that exploded:

The blinking spot is the approximate location of the pulsar.  
The thin filament seen in Ha (red) going to the left and upwards slightly, follows  the line of apparent motion of the neutron star superimposed on the pulsar wind (see below). 
There is still some debate as to whether this structure was responsible for the supernova due to it's off-center location.  The assumption is that it was an asymmetric blast. 

The Neutron star was only recently discovered.  It was not detected in visible light, but found by the Chandra X-ray observatory along with a surrounding pulsar wind nebula:
Chandra X-ray image

Though Chandra detected the x-ray source, pulsations were not detected.  The estimated period is 0.1-0.6 seconds, which was below the sensitivity of the equipment, i blinked it at .2 s ;)

The second box, upper right, looks like it might be a small planetary nebula.  
However, SIMBAD lists a star cluster, molecular cloud, and bright nebula at this location--no planetary nebula:
Teutsch GN J0615.3+2253 -- Bright Nebula
  6 15 21.1 +22 53 27

Image details:
When I first shot it, I forgot that it was a supernova remnant and took a few test shots in SII and NII, only to find that they appeared to simply mirror the Ha with much weaker signal.
Despite imaging with narrower band width and 2x binning, the OIII is still much more faint than the Ha.
FS102, SX Trius 694 FL 627.3 mm, 1.49"/Pixel unbinned, reduced in photoshop to 3.9"/px
astrodon 5nm Ha, 3nm OIII filters
Ha 102x10 min + 20x10 min bx2
OIII 152x10 min bx2
total 45 hours 40 minutes ;)
1/14-2/23/2018, bortle white skies
eastbluff, CA

Sunday, June 10, 2018

first Jupiter of the year 6/8/18 6 AM UTC good seeing

Here's my first jupiter of the year:
Jupiter and moons 2018-06-08-0512 UT

seeing was unusually good:
Jupiter 2018-06-08-0611_1 R-G-B

spent all last year tweaking equipment trying to get a good planetary image and got mush.  this year, first time out with older equipment i got lucky with good seeing, blowing away anything i did with my fine tuned rig last year :(

a few comparisons for imagers:
RGB camera up sampled 2x vs barlow:
RGB camera upsized x2
RGB camera 2x barlow
close, but very slight edge to the barlow

RGB camera barlowed 3x2 minute runs combined:

mono camera 1 minute x 2 each channel:

corrector fogged out before i could get a barlowed mono image :(

image details
celestron nexstar 8 GPS (8" SCT on a wedge)
wide view
2 minutes with firecapture 5 ms exposures @ 21 fps
6/8/18 5:12 UTC

large view
ZWO RGB filters,
2x60 second captures for each filter R G B
captures with firecapture ~5ms @ ~180 fps 30% histogram
6/8/18 6:11 UTC
stacked in autostakkert (upsampled x2), combined in WinJupos, sharpened in registax 6
final combine in photoshop

not shown: IR filter added little
adding small boxes closer to the edge in autostakkert, gave better peripheral detail

Southern California