Sky and Rockets
Tuesday, April 21, 2026
Building Permit Received - Construction Starts on Night Sky Observatory
Thursday, April 16, 2026
Soldiers Delight Star Party - April 18, 2026 - 8:30pm EDT
Soldiers Delight Star Party - April 18, 2026
Don't miss the next SD Star Party - this Saturday evening!
"Crisis in Cosmology - aka, The Hubble Tension"
Tonight's lecture is on one of the most intriguing puzzles in modern cosmology: The Hubble Tension. This phenomenon refers to the discrepancy between the rate of expansion of the universe as measured by different methods. On one hand, we have measurements from the early universe, such as those from the Cosmic Microwave Background (CMB), and on the other, we have measurements from the local universe, such as those using Cepheid variables and Type Ia supernovae. Despite the precision of these methods, they yield different values for the Hubble constant, leading to a tension that challenges our understanding of the cosmos. Today, we will delve into the methods used to measure the Hubble constant, explore the possible reasons for this discrepancy, and discuss the implications for our understanding of the universe.
All ages welcome.
All programs rain or shine. Time machines will be provided by the Westminster Astronomy Club.
You can find out about special local events by contacting us at https://www.westminsterastro.org/
Date: Saturday, March 18, 2026
Note time change for the Summer Months:
Time: 8:30 p.m. - 10:30 p.m. Eastern Daylight Time (EDT)
Location: Soldiers Delight Environmental Area - Visitor Center
5100 Deer Park Rd.
Owings Mills, MD 21117
Monday, April 13, 2026
New Images
First up, the Eyes Galaxies (NGC 4438 and 4435)
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| The Eyes Galaxies EdgeHD11/ASI2600 - April 8-10, 2026 LRGB - 6hr 21m integration time |
Next, M64 (the Black Eye Galaxy)
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| M64 - the Black Eye Galaxy EdgeHD11/ASI2600 - April 12, 2026 LRGB - 6hr 24m integration time |
Sunday, April 5, 2026
Goodbye Comet MAPS
Friday, March 27, 2026
Latest on the Kreutz Sungrazing Comet C/2026 A1 MAPS
So, the big question is will MAPS be a great comet?
SkyandTelescope has a good article by Bob King on the expectations for comet MAPS. Great simulation/animation by French optical engineer and amateur photographer Nicolas Lefaudeux is included.
Monday, March 23, 2026
SkyShed POD-S Delivered today
Sunday, March 15, 2026
Update on comet C/2026 A1 (MAPS)
On its way to a close encounter with the Sun, with perihelion expected on April 4–5, 2026, comet MAPS is steadily brightening. By mid-March, it had reached magnitude 10—still far too faint to spot without optical aid. However, as it moves deeper into the inner solar system, and if it survives its close approach, it could make an appearance in Earth’s skies around Easter.
| Gerald Rhemann and Michael Jäger - March 10, 2026. |
In early April, some models predict it might shine as brightly as Venus, the brightest planet. But that’s likely an optimistic guess. It will probably reach a magnitude of 1 to -2, making it about as bright as some of the more prominent stars. These estimates are based on its brightness (18th magnitude) when it was still twice Earth’s distance from the sun. Magnitude 18 is far too faint to see with the naked eye, but it’s actually quite bright for a comet at that distance.
Sungrazers can be breathtaking, but their close proximity to the sun makes them hard to see. Even if MAPS glows as brightly as Venus, it will remain near the sun and low on the horizon. Here's a diagram showing the location of MAPS on April 4, at 6:30pm. Notice how close it is to the sun and only about 13° in altitude. Even at magnitude -4 (Venus' brightness) the sun is 1 billion times brighter! Still, there’s a chance we could witness something truly historic.
| April 8, 7:30pm |
As the month progresses, MAPS will get a bit higher in somewhat darker skies. At 8:00pm on April 15th, altough still low in the western sky (10-15° high), it should become easier to see as the sun is now 4° below the horizon.
By the end of April, it begins to drop in altitude and will grow much dimmer as it moves away from the vicinity of the sun.
Plan ahead and pick a spot with a clear view of the western horizon. We just might get to see another Ikeya–Seki.
Wednesday, March 11, 2026
Soldiers Delight Star Party - March 21, 2026 - Topic: The James Webb Space Telescope
Soldiers Delight Star Party - March 21, 2026
Don't miss the next SD Star Party:
"Unlocking the Cosmic Secrets: The James Webb Space Telescope"
Join us on a captivating journey beyond the visible spectrum! The James Webb Space Telescope (JWST), one of humanity’s latest cosmic sentinels, has already started to revolutionize our understanding of the universe. Imagine peering through the veil of dust and time, witnessing the birth of galaxies, the dance of exoplanets, and the cosmic symphony of star formation. In this exclusive talk, we’ll delve into the cutting-edge science, awe-inspiring innovations, and mind-boggling discoveries that JWST has provided. Buckle up, stargazers—Webb has already challenged our understanding of the Universe and is continuing to unveil the cosmos as never before!
All ages welcome.
All programs rain or shine. Time machines will be provided by the Westminster Astronomy Club.
You can find out about special local events by contacting us at https://www.westminsterastro.org/
Date: Saturday, March 21, 2026
Time: 6:30 p.m. - 8:30 p.m. Eastern Daylight Time (EDT)
Location: Soldiers Delight Environmental Area - Visitor Center
5100 Deer Park Rd.
Owings Mills, MD 21117
Monday, March 2, 2026
Stretching and HDR Processing
Stretching
HDR Multiscale Transformation
Applying the Processes
The Science of Image Stacking - Experimenting with Sub Exposure Times
Instead of taking one very long exposure (which can be ruined by a plane crossing the field or wind moving the equipment), astrophotographers take many shorter exposures of the same object (a galaxy, nebula, star field, or planet). Each image records the signal (real light from stars and deep-sky objects) as well as noise (random fluctuations from the sensor, heat, electronics, and sky background).
Because astronomical objects are effectively static over short time spans, these multiple images contain the same signal but different random noise patterns. Since the signal is consistent across images it adds together as the individual subs are built up, but the noise is random and averages out toward zero. As a result, the signal-to-noise ratio (SNR) improves by the square root of the number of images stacked (√N).
Indeed, the sky background, due to excessive light pollution, limits exposures of under 3-5 minutes in order to prevent the object from being swamped out. In very dark skies this is not generally a problem; but near cities where streetlights and buildings are dense, it is.
Noise is the biggest enemy in low-light imaging. Stacking reduces random noise far more effectively than any single long exposure, producing smoother backgrounds and cleaner detail. In addition, stacking allows bright stars and faint structures to coexist in the same image without clipping highlights or crushing shadows, revealing more tonal information across the scene.
In summary, image stacking works because math beats physics: Physics limits how much light a single exposure can collect without noise while statistics allow many imperfect images to combine into one high-quality result allowing modern amateur astrophotographers to produce images that rival professional observatory photographs from decades ago.
Of course, you need to determine an appropriate exposure time to capture the needed photons (if no photons are picked up by the sensor it doesn't matter how many subs you stack in the end). But you can limit the exposure time by quite a bit depending on the object of interest.
As an example of just how well this works, I imaged the famous Orion Nebula, M42, with my EdgeHD telescope in Hyperstar mode (an f/2 optic train). This nebula is the brightest nebula in the night sky. A single 60 second exposure can give you a nice result (albeit a bit noisy). A ten-minute exposure would really bring out the detail. But 10 minutes is way too long of an exposure in the light polluted sky of my backyard. The science of stacking, however, claims that a stack of ten, 1-minute exposures would provide the same image as a single ten-minute exposure with the added benefit of reduced noise, hence better SNR.
Here are three final photos of the Orion Nebula taken with differing sub-exposures and stacked to provide the total integration time of ten minutes.
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| 80x8sec |
Can you see any differences? In fact, looking at the original images (these are reduced size JPGs for posting here) the 80x8sec stacked version is noticeably better in terms of SNR, although the post processing software I use has some terrific noise reduction tools that were used in the creation of these images.
The drawbacks of this are few, but worth mentioning. It takes 8 times the storage to hold the 80 8-sec subs vs the 10 60-sec subs and the post processing time (and required storage on the computer) also goes up. But this is a small price to pay for such wonderful results.
Saturday, February 28, 2026
Total Lunar Eclipse this Tuesday Morning
Building Permit Received - Construction Starts on Night Sky Observatory
It's been a long time waiting (almost a month to the date) for my building permit to get approved and issued prior to starting the const...
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Like in any tech field, advancements in technology, tools, and processes keep pushing the boundaries of what’s possible, and astrophotograph...
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We had an unscheduled ' entertainment ' activity last evening (actually, early morning of the 13th). The ship ran into a fairly lar...












