The Fly, Medusa and the Eskimo

NGC 1931, the Fly Nebula. 6 x 120 s at ISO 1600 and 23 x 180s at ISO1600. I only targeted this because the end of my shed (=observatory) was blocking the view of the Medusa Nebula. So, I had sometime to wait until it was high enough  to image.

NGC 1931 Fly Nebula in Auriga

Wikipedia: NGC 1931, is an emission and reflection nebula in the constellation Auriga. The nebula has been referred to as a "miniature version of the Orion Nebula", as it shares some of the same characteristics. It is a mixed emission-reflection nebula, and contains a smaller version of the Trapezium in its hot young star cluster centered in the emission nebula. The entire cluster/nebula complex is only about 3 arcmin in size. The distance from earth is estimated at about 7000 light years.

The Medusa Nebula. I thought I had previously collected over three hours of data on this object, to find the catalogue coordinates were incorrect.
Incorrect (but in Wikipedia and the catalogues in Astrophotography Tool)
                                                              RA 7h 29m 3s        | Dec +13° 14′ 48″
Correct:                                                 RA 7h 29m 11s       | Dec +13° 15′ 57″

 This image is based on 26 x 180 s exposures at ISO1600.

Abell 21, Medusa Nebula in Gemini

Wikipedia: The Medusa Nebula is a large planetary nebula in the constellation of Gemini on the Canis Minor border. It is also known as Abell 21 and Sharpless 2-274. It was originally discovered in 1955 by UCLA astronomer George O. Abell, who classified it as an old planetary nebula. The braided serpentine filaments of glowing gas suggests the serpent hair of Medusa found in ancient Greek mythology.

Until the early 1970s, the Medusa was thought to be a supernova remnant. With the computation of expansion velocities and the thermal character of the radio emission, Soviet astronomers in 1971 concluded that it was most likely a planetary nebula.

As the nebula is so big, its surface brightness is very low, with surface magnitudes of between +15.99 and +25 reported. Because of this most websites recommend at least an 8-inch (200 mm) telescope with an [O III] filter to find this object although probably possible to image with smaller apertures.


The Eskimo Nebula in Gemini looks like a blue star that's not quite right! It's pretty small in my telescope and I think is probably overexposed. This image is based on 22 x 180s exposures at ISO 1600. The inset shows some detail.

Eskimo Nebula in Gemini

The Eskimo Nebula (NGC 2392), also known as the Clownface Nebula or Caldwell 39, is a bipolar double-shell planetary nebula (PN). It was discovered by astronomer William Herschel in 1787. The formation resembles a person's head surrounded by a parka hood.

Not enough data but a quick look at IC447 in Monoceros while waiting for the good ol' meridian flip:

IC447 in Monoceros

Wikipedia: IC 447 is a reflection nebula in the constellation Monoceros. In astronomy, reflection nebulae are clouds of interstellar dust which might reflect the light of a nearby star or stars. The energy from the nearby stars is insufficient to ionize the gas of the nebula to create an emission nebula, but is enough to give sufficient scattering to make the dust visible. Thus, the frequency spectrum shown by reflection nebulae is similar to that of the illuminating stars. Among the microscopic particles responsible for the scattering are carbon compounds (e. g. diamond dust) and compounds of other elements such as iron and nickel.

Gemini Deep Sky Objects and a supernova

Finally a couple of really crisp clear night and no moon!  My targets for the 18th were Jellyfish nebula in Gemini and, while I was waiting for the meridian to pass, I had a look at a pair of interacting galaxies in Taurus, NGC 1410 and NGC 1409, plus a few minutes on Messier 100, which has a supernova visible, first reported on  the 7th Jan.

The Jellyfish Nebula, IC443,  image is based on around 3 hours of data, 180 s  at ISO 1600.

Jellyfish Nebula in Gemini

Wikipedia:IC 443 (also known as the Jellyfish Nebula and Sharpless 248 (Sh2-248)) is a galactic supernova remnant (SNR) in the constellation Gemini. On the plane of the sky, it is located near the star Eta Geminorum. Its distance is roughly 5,000 light years from Earth.

IC 443 may be the remains of a supernova that occurred 3,000 - 30,000 years ago. The same supernova event likely created the neutron star CXOU J061705.3+222127, the collapsed remnant of the stellar core.

The next image shows you need a lot more data sometimes! I only took around 30 mins in total, so, with the size of aperature of my telescope, all we have is fuzzy blobs.

A Pair of interacting galaxies, honest!

Still relatively few exposures (8 x 180 s at ISO 1600), but a much better image of Messier 100. Various fuzzies around it are some of the many thousands, millions, billions of galaxies  outside our own. On 7th Jan it was reported that there had been a supernova in M100. It can just be seen on the right of the core in the inset.

Messier 100, with the supernova near the core (see magnified inset)

Wikipedia: Messier 100 (also known as NGC 4321) is an example of a grand design intermediate spiral galaxy located within the southern part of constellation Coma Berenices. It is one of the brightest and largest galaxies in the Virgo Cluster, located approximately 55 million light-yearsdistant from Earth and has a diameter of 107,000 light years, roughly 60% the size of the Milky Way.

Seven supernovae have been identified in M100. In March 1901 the first supernova of M100 was found, SN 1901B, a type I supernova found with a magnitude of 15.6 at 110"W and 4"N from its nucleus. SN 1914A was then discovered in February to March 1914; its type was undeterminable but was found with a magnitude of 15.7 at 24"E and 111"S from its nucleus. Observations of M100 from February 21, 1960 to June 17, 1960 led to the discovery of SN 1959E, another type I supernova,with the faintest magnitude, 17.5, among the five found, at 58"E and 21"S from its nucleus. On April 15, 1979, the first type II supernova found in the M100 galaxy was discovered; however the star SN 1979C faded quickly; later observations from x-ray to radio wavelengths revealed its remnant. The fifth supernova was discovered February 7, 2006; the star SN 2006X had a magnitude of 15.3 when discovered two weeks before fading to magnitude +17. Supernova SN 2019ehk, discovered on April 29, 2019, reached a peak magnitude of approximately 15.8. The seventh supernova, SN 2020oi, was discovered on January 7, 2020.

The Bear and the Hunter

My first target this fine clear night was the first of a pair of galaxies in Ursa Major. This is M81, or Bode's Galaxy.

M81 Bode's Galaxy

This is the second of the pair of galaxies in Ursa Major, This is a starburst galaxy, rich in newly forming stars,

M82 The Cigar Galaxy

Wikipedia: Messier 82 (also known as NGC 3034, Cigar Galaxy or M82) is a starburst galaxy approximately 12 million light-years away in the constellation Ursa Major. A member of the M81 Group, it is about five times more luminous than the whole Milky Way and has a center one hundred times more luminous than our galaxy's centre.] The starburst activity is thought to have been triggered by interaction with neighboring galaxy M81. As the closest starburst galaxy to Earth, M82 is the prototypical example of this galaxy type.

You just have to take a pic of M42 this time of year! It is a difficult object since the centre (where the trapezium is) is so bright that it gets blown out when trying to show the fainter edges. Hence the two images here, one to show the Trapezium.

M42 The Great Nebula in Orion

 Wikipedia: The Orion Nebula (also known as Messier 42, M42, or NGC 1976) is a diffuse nebula situated in the Milky Way, being south of Orion's Belt in the constellation of Orion. It is one of the brightest nebulae, and is visible to the naked eye in the night sky. M42 is located at a distance of 1,344 ± 20 light years and is the closest region of massive star formation to Earth. The M42 nebula is estimated to be 24 light years across. It has a mass of about 2,000 times that of the Sun. Older texts frequently refer to the Orion Nebula as the Great Nebula in Orion or the Great Orion Nebula.

The Trapezium in the middle of M42

Wikipedia: The Orion Nebula contains a very young open cluster, known as the Trapezium due to the asterism of its primary four stars. Two of these can be resolved into their component binary systems on nights with good seeing, giving a total of six stars. The stars of the Trapezium, along with many other stars, are still in their early years. The Trapezium is a component of the much larger Orion Nebula Cluster, an association of about 2,800 stars within a diameter of 20 light years.

The Horsehead Nebula was revisited. I have managed to get over an hour of data, mostly  240s @ ISO 1600. So, the noise level is reduced quite a bit

Horsehead Nebula in Orion

Wikipedia: The Horsehead Nebula (also known as Barnard 33) is a small dark nebula in the constellation Orion. The nebula is located just to the south of Alnitak, the easternmost star of Orion's Belt, and is part of the much larger Orion Molecular Cloud Complex. It appears within the southern region of the dense dust cloud known as Lynds 1630, along the edge of the much larger, active star-forming H II region called IC 434.
The Horsehead Nebula is approximately 422 parsecs or 1375 light years from Earth. It is one of the most identifiable nebulae because of its resemblance to a horse's head.

The glare from Alnitak (the most eastwards of the three stars in Orion's Belt) can be seen on the left of the image.

NGC 2403 , the Moon and a Comet

NGC 2403, this time with over 3 hours of data, 100 x 120 s exposures at ISO 1600.

NGC 2403 in Camelopardalis

Compare this with the images in the previous entry!


The Moon was just after first quarter, so the terminator was pretty interesting:

Moon just past first quarter

Mosaic showing the terminator

Aristillus, Autolycus and Archimedes

Alpine Valley

Mare Vaporum

The comet was C/2017 T2 Panstarrs. Again, it moved noticeably between each of  the 3 minute exposures. Clouds were appearing, so I had to ditch some exposure and ended up with a shorter session than I had hoped.