Originally Posted by j.gardavsky Hello all,
this is a short report on a short observing session with my 6" F/5 achromatic refractor. Abell 7 planetary nebula in Lepus
The Abell 7 touches a triangulum of 8mag – 9mag stars about 2° west off Mu Leporis, so its position is easy to find.
With its large extent of 871“ x 670“, and low surface brightness, it has been for a long time on my to-do list.
Close to 20:00, the Zeiss (magnification 58.6x) eyepiece with the UHC filter has
Originally Posted by not_Fritz_Argelander https://arxiv.org/abs/1701.01840
Over the past few decades, a consensus picture has emerged in which roughly a quarter of the universe consists of dark matter. I begin with a review of the observational evidence for the existence of dark matter: rotation curves of galaxies, gravitational lensing measurements, hot gas in clusters, galaxy formation, primordial nucleosynthesis and cosmic microwave background observations. Then I discuss a number of anomalous signals in a variety
I forgot to mention that I did raise the gamma a smidge before the final step. Sorry I forgot to mention that. Originally Posted by JohnP_1 Here is what I came up with. Note that I first convert the jpeg to a 16 bit image removing the jpeg artifacts. Also, I included a snapshot of when I adjusted one of the color curves to give you an idea of what I'm talking about. With the Carboni actions for PS, I edited all or most of them to delete the conversion to 8 bit mode that he included in most. I only convert
Deep in the heart of winter here in the north, with its cold (sometimes brutally so) temperatures and sometimes crystal clear skies, the stars seem to shimmer like diamonds casually tossed onto a jeweler’s mat of black velvet. While this is a wonderful season to plunder the myriad of open clusters along outer portions of the galactic plane, there are also numerous planetary nebulae that dot the sky on these cold winter evenings. Our friends to the south, with their summer season in full bloom, also
Southern Celestial Hemisphere NGC 2438 (Puppis):
Planetary nebula, mag=10.8, size=73.0”x68.0”, SBr=10.8 mags/arcmin2
We now swing south of the celestial equator to Puppis. This constellation is one of three parts of what was once the most expansive constellation known in antiquity, Argo Navis. Listed by 2nd century astronomer Ptolemy in his Almagest, it represented the ship used by Jason and the Argonauts in pursuit of the Golden Fleece. Over time,
Updated 02-01-2017 at 12:06 PM by KT4HX