Saturday, May 9, 2026

Three New Images from 'the soon to be constructed' Night Sky Observatory

Observatory Plans

Plans for the groundbreaking of the new observatory building, Night Sky Observatory, are almost complete. Hopefully I can start digging the hole for the pier footing next week or soon after. I have all the parts except for the lumber, sonotube and concrete. Digging the hole is straightforward, but I need to have the lumber for the deck available to make sure the height of the concrete top is at the right distance from the deck floor when constructed. Once the concrete is poured it's all said and done - no more changes (at least not easy ones!).

Meanwhile, I was able to capture and process a few more deep space images. 

NGC 3242 - Jupiter's Ghost

Drifting through the constellation Hydra, NGC 3242 is a striking planetary nebula commonly known as Jupiter’s Ghost. The nickname comes from its nearly planet-sized apparent disk and vivid blue‑green glow, which early astronomers likened to the appearance of Jupiter through small telescopes. In reality, this object has nothing to do with the planet—it marks the final visible breath of a Sun‑like star that shed its outer layers near the end of its life, leaving behind a hot, dense white dwarf at its core.
NGC 3242 (HOO) - March and April, 2026
EdgeHD11/ASI2600mm
1hr 50min total integration time (Ha and Oiii)

Jupiter’s Ghost reveals beautifully layered structure: a bright elliptical inner shell, delicate outer halos, and subtle knots and jets sculpted by fast stellar winds and intense ultraviolet radiation. The characteristic turquoise color is dominated by doubly ionized oxygen glowing at specific wavelengths, giving the nebula its ethereal, eye‑like appearance. Though this cosmic shell spans roughly a couple of light‑years, it is fleeting on astronomical timescales—destined to fade as the central star cools and the nebula disperses into interstellar space.

HDR processing was used to highlight the inner structure. This is a cropped version of the original stacked image.

Arp 104

Arp 104, also known as Keenan’s System, is a striking example of an interacting galaxy pair captured in Halton Arp’s Atlas of Peculiar Galaxies. It consists of two galaxies—NGC 5216, an elliptical galaxy, and NGC 5218, a highly disturbed disk galaxy—locked in a close gravitational encounter in the constellation Ursa Major. The most eye‑catching feature of the system is the faint but distinct bridge of stars and tidal material connecting the two galaxies, a structure formed as their mutual gravity pulls stars out of NGC 5218 and stretches them across intergalactic space.
Arp 104 (LRGB) - April 2026
EdgeHD11/ASI2600mm
5hr 24min total integration time

This stellar bridge, spanning roughly 22,000 light‑years, offers a vivid snapshot of galactic interaction and evolution in progress. The encounter has triggered structural distortions and star formation, particularly within the dusty central regions of NGC 5218, while NGC 5216 appears comparatively calm and evolved.

NGC 4561 - Umbrella Galaxy

NGC 4651, often called the Umbrella Galaxy, is a striking spiral galaxy in Coma Berenices, roughly tens of millions of light‑years from Earth, whose serene appearance hides a dramatic past. At first glance it shows a beautifully structured, nearly face‑on disk with sweeping spiral arms and a bright, compact core. But deep exposures reveal the real showpiece: a long, delicate tidal stream arcing outward like the handle of an umbrella. This faint stellar plume is the remnant of a smaller galaxy that NGC 4651 tore apart and absorbed, leaving behind a graceful ribbon of stars that wraps around the system.
NGC 4561 (LRGB) - April 2026
EdgeHD11/ASI2600mm
5hr 2min total integration time

Once again, I’ve had some issues with my flats not completely correcting my lights. So, I’ve cropped this image slightly to exclude the artifacts. And yes, once again PixInsight failed to register all the subs complaining about 3 red, 16 green and 8 blue. So, I used APP to do the calibration and registration (although I could have just supplied the PI calibrated subs). All lights were successfully registered.

Friday, May 1, 2026

The 'Need' for Infinity

Ultrafinitism, a philosophy that rejects the infinite, has long been dismissed as mathematical heresy. But it is also producing new insights in math and beyond.



This is a bit outside the usual scope of the blog, but it popped up in my email and caught my attention. I’m not planning to dive into it myself, but I’m sharing it to see what everyone else makes of it. An interesting read at Quanta Magazine. Comment below if you like.

Three New Images from 'the soon to be constructed' Night Sky Observatory

Observatory Plans Plans for the groundbreaking of the new observatory building, Night Sky Observatory, are almost complete. Hopefully I can ...