Saturday, October 21, 2017

M76 in Perseus

Little Dumbbell Nebula

Unlike the first planetary nebula I saw (M27 Dumbbell Nebula), M76 is not an easy binocular target. I have tried to see it from rural dark skies with my 15x70 binoculars and failed. However, it is visible from suburban skies even with a small telescope.  

This little guy was discovered in 1780 by a french astronomer named Pierre Mechain who shared his discovery with Charles Messier and therefore it was included in the Messies List. Although, it was not until 1918 that was recognized as a planetary nebula by the American astronomer Heber Doust Curtis. It was baptized as little dumbbell because it resembles its big brother M27. I personally think that this one looks more like a peanut shell rather than a dumbbell.

Finding M76 is not a difficult task since it is located close to two fairly bright stars in the foot of Andromeda and the hand of Perseus: 51 And and Phi Persei respectively. From this last star, one can hop less than a degree to HIP8063 and once there, the peanut smudge will show up in the FOV of a low magnification eyepiece.

In small  to mid sizes scopes, M76 only show a defocused central bar sorrounded by a very dim glow but even with my 6 inches of aperture and 100 magnification I needed to use averted vision to discern the shape of a peanut shell. According to sketches I have seen from large telescope users, M76 will show more of its bipolar structure: two lobes formed by the material ejected off of the star equator. In photographs, a central nucleus of 16th magnitude can be seen.

If you have clear skies, this is a good time to go out and hunt for M76 with the telescope. Hope you have enjoyed my short report.



Greetings,



LG


Edited by Jennifer Steinberg (editor in chief).



Monday, October 16, 2017

Chasing Comets

C/2017 O1 (ASASSN)

My first comet ever seen was C/2012 ISON, back in 2013 from Colombia, and my first comet seen from China was  C/2014 Q2 Lovejoy, both in binoculars. ASASSN1 has some significance because it
Click to enlarge image
is my first comet seen in the US. This was the first comet discovered by the All-sky Automated Survey for Supernovae (ASASSN) on the last 19th of July.  This year, it was expected to reach maximum brightness (around magnitude 9.3)  by mid October when it reached perihelion at around 108 million kilometers from Earth, beyond the orbit of Mars.  

Last 13th of October, friday night, I set up the scope early with the purpose to catch ASASSN in the first hours of Saturday. I had to wait until the constellation of Perseus would make its way through the giant trees around, but also I wanted to avoid the moon glance, to keep the sky as dark as possible.  However, Stellarium was reporting this comet as magnitude 12.05, so I was a little skeptical about being able to reach it with the telescope.

When Perseus had gotten up at a good altitude above the trees at 2 in the morning,  I aimed the scope at bPer with the red dot finderscope and then went to the RACI view. From there, I went down looking for the comet and suddenly stumbled into a lovely parallelogram made by 4 stars; HIP 21972 was the brightest of all.  Once I had landed there with the RACI, I went to the 40mm eyepiece eyepiece. To look for comets and other dim stuff I rather prefer to hunt with a low magnification eyepiece and my hunter is the 40mm Celestron Omni.  What I saw through the eyepiece view was the comet: a dim central stellar core sorrounded by a fuzzy bluish/gray halo.  The core was as dim as the closest star, reported in Stellarium as magnitude 11.20 so I estimated the core to be at 11th magnitude too, information that matches with the report for that date in the website of sky live.

With the Comet in middle of the FOV, I decided to try more magnification, so I tossed the 15mm Luminos eyepiece on to see what it could reveal. The core was almost gone, but two tiny background stars appeared close to the comet’s core. With averted vision I thought I saw traces of a tail of the comet, but I could not confirm them later. I finally decided to perform a sketch of the area using the lowest magnification possible and the sketch featured is a result of that sketch processed in photoshop.

If the sky is clear, this is a good time to search for ASASSN because lunar phases are heading to New Moon.

Good hunt!


LG


Edited by: Jennifer Steinberg (editor in chief)



Sources

Monday, September 25, 2017

Caldwell 28

A ghosty cluster among the stars

The other night I was stargazing  from my little window of sky between the trees and stumble into the constellation of Andromeda. After watching Andromeda Galaxy and its two companions, M32 and M110 for several minutes, I decided to hunt for a new object that I had not record before. Stellarium was showing me an open cluster in the skirts of Andromeda: C28, a discreet 5.7 magnitude open cluster.

At the time of the observation, 23:36 hours, Andromeda had reached an altitude of 40 degrees over the eastern horizon. High enough to avoid local light pollution, but the whole area was touched by the huge dome of light pollution coming from Silicon Valley.

Making it to the area was not a challenge, but due to the low magnification in the binoculars, seeing the components of the cluster was relatively difficult. Most of those dim unresolved stars turn into hazy areas slightly lighter than the background.

In the sketch, there are three groups of stars that could be  the cluster, but only one is. The first group of bright stars makes a hook shape, below them, there is a second group with most of its stars forming a crown shape and finally, almost touching the lower edge the of FOV there are some scattered stars. That is where the open cluster is located. Try to enjoy the sketch in a dark room to see the subtle details in the background and around the cluster. This is a close simulation of the view in my Bortle 5 skies in US.





Thanks for reading!


LG


Edited by Jennifer Steinberg (editor in chief).