Hunting for Galaxy M61

Hunting for Galaxy M61

I am under no illusion that seeing galaxies is possible from my location on Earth.  Around 30 miles outside of Chicago is still one of the worst locations for light pollution anywhere.  While I can see the core of the Andromeda Galaxy from my backyard, through binoculars, it appears like a fuzzy star, shown here. But Andromeda is very close to our Milky Way and on a collusion course with it.  So excluding M31, no other galaxy should be possible to view unaided.

Nonetheless, I was inspired by Roger Powell’s excellent imaging of M61 and particularly his finding of a supernova back in May. At the least, I thought, I may be able to find the approximate location of M61 and supernova SN 2020 jfo, to say that I “saw” it, if only the black void of area within my telescope’s eyepiece.

As are all of his posted pictures, Roger’s image of M61 is impressive, made possible by very long exposures driven by equitorial tracking to compensate for the Earth’s rotation.  Long exposures of deep sky objects allow the scarce photons from galaxies, millions of light years away, to collect on the camera’s sensor and accumulate, allowing galaxies to take shape in ways impossible by unaided telescope viewing.

So how does one go about finding this galaxy, M61?  Where is it in the sky?  From our perspective on Earth, it resides in the constellation Virgo and near Leo.  On mid June evenings it was up in my Southwest sky.  Here is the location of M61 in my sky (N 41 / W 88) at about 11 p.m. local time a few weeks ago.

(As with all images in this particular post, I highly recommend clicking each to see the full picture.  Otherwise, you will be missing details and perspective referenced in the narrative.)

Virgo is a relatively dim constellation in my sky, outside of the star Spica and a few others.  Leo can easily be found by its edge stars of Denebola near Virgo and famous Regulus on the opposite end.  There are a few faint but visible stars between them.  These can be used as “guide stars” to approximate the location of where to point your telescope.

Here is a closer view of that area of space (M61 is denoted by the square brackets):

This picture, from Stellarium, makes it almost too easy to find the location, since there are so many much fainter stars that can act as guides.  But what do I really see through my area’s light pollution? Compensating for pollution, Stellarium provides a view closer to reality:

This truly is what I have to work with, even on the best of nights and when there is no Moon, like there was for most of mid June.  With so little information in the sky, how can you even hope to get close to an “invisible” object?  Enter imaginary lines and basic geometry.

M61 lies almost on a straight line between Denebola and another faint but visible star in Virgo, named Porrima.  Looking at the sky, I roughly approximated that M61 was about a third of the distance from Porrima to Denebola.  Further, I noticed, in Stellarium, that Porrima and another visible star form an isosceles triangle with M61.  So assuming these two factors – the straight line and that triangle and where they should intersect – I had a very good idea of the general area where I should point my telescope at!

But even by doing these rough estimates, how would I know if my guess was right?  Fortunately, Stellarium allows you to simulate telescopes, eyepieces, and lenses, so you can get a view at the computer extremely close to what you should actually see.

We get to see what should be our “telescope” view.  Obviously, we won’t see the galaxy as shown; the little graphic is just a marker.  But what we should be able to make out are most of the surrounding stars. Keep in mind that this image/simulation compensates for the vertical and horizontal image flipping inherent of Newtonian reflector telescopes (essentially, the image appears upside down).

All of these stars are still relatively dim.  However, I noticed there is one “bright” star near M61 that could be used as a guide in my telescope’s mounted viewfinder.  It is just below the area of M61 and named c.Vir.

So using my telescope’s viewfinder (which is effectively a mini telescope in its own right), I could easily find c.Vir.  And fortunately, given my eyepiece (Q70), c.Vir and M61 could fit within the same view, as shown here by Stellarium:

Notice that there are three stars very close to c.Vir, two above (actually below, given the telescope’s mirror flip), and one below (actually above).  They form a unique pattern that should be easy to identify.

On June 7th I made my first attempt to locate M61.  I used the drawing application Procreate on my iPad, along with an Apple Pencil. Sometimes I feel like an Apple commercial (I have mentioned the benefits of my iPhone, iPad, and Apple Watch for astronomy previously), but it really is an excellent setup, able to replace traditional pencil and paper.  I need to practice my drawing and using Procreate, but still I was amazed how easy it was to start sketching with little preparation. Here is the first sketch I took with Procreate, on June 7th:

I used a red background with white pencil, since red light is best to keep your night vision.  Afterward, I replaced, via PaintShop Pro, the red with black to make it easier to see here.  I will only show the black edits of subsequent sketches.  And in subsequent sketches, I replaced the above red with an even darker red, which helped my night vision even more.

Unfortunately, that first night I considered a failure, as I was unable to align my very crude star patterns with anything in the vicinity of M61.  It was after this first night that I went back and truly studied Stellarium, found c.Vir, and memorized the star formations around M61.

My next viewing attempt came on June 14th.  This time, knowing a little more about what I should look for, I drew this sketch:

Aha!  Now we are getting somewhere.  This at least looks somewhat like the simulations in Stellarium.  You must see the full image to identify the fainter stars, particularly near the bottom.

At this stage, I feel it important to note that I was not “cheating” at the telescope.  My PC desktop was inside my house, and I did not reference it while drawing at the telescope.  I had planned to find c.Vir and then star hop “down” (actually up) to find the stars near M61.  The results of that night, about 20 minutes of viewing, are in the above sketch.

In post-analysis I found this image interesting on two fronts.  c.Vir is easily identifiable.  This allowed for an easy star hop down (again, actually up) to M61’s neighborhood.  Zooming into my own sketch, I am fairly confident in identifying the location of M61:

Also identified here is my guess at the location of galaxy NGC 4301.  I referred back to Roger’s M61 image, cross-referenced with Stellarium, to estimate this location within my sketch.  I thought this important as it helps to give perspective in size from my sketches and his picture that started my trek.  Note how many stars Roger captured within this small space!  I assume many of those visible are of the 12+ magnitude range.

The sad news is that, based on my guesses, I saw nothing of M61 directly on June 14th.  But this was not unexpected.  Still, I wanted to give the hunt one last try.  In preparation, I noted the two “anchor” stars (my term) closest to M61, that would allow me to hopefully focus that area with the help of my 2x Barlow lens.  From Stellarium:

The brighter, HIP 60224, is magnitude 8.15.  The unnamed star below it has a magnitude of 10.35.

On June 15th, I looked at this area of space with the same telescope setup as the prior night, but this time using the Barlow lens to double the magnification.

In this sketch, HIP60224 is the brightest dot, and the unnamed 10.35 star is below it on an angle to the right.  These two, I saw very easily.  What was not easy were the three other stars drawn to their right and above.  I cannot emphasize enough how difficult it was to see these.  I had to use my peripheral vision and stare at the area several times over.  Vibrations in the telescope and atmospheric distortions were obvious.  These stars were clearly at the limits of both my equipment and my own visual abilities, within my light polluted sky.

In hindsight, I think those three stars are too far to the left of M61 to be near the galaxy’s core or even possibly the supernova.  Thus my exploration for M61, at least in 2020, has come to an end.  The supernova is now too faint and should disappear soon.

As a side trek, since I already had my Barlow and virtual sketchpad available, I decided to look one last time at c.Vir.  Interestingly, I clearly saw a third star next to the earlier pair of two:

The top star of the original two-pair is listed as magnitude 10.05.  I assume this third star is at least magnitude 12, maybe higher.  It was fainter than the other two, though that doesn’t quite come through in the sketch.

Although I did not find M61 or the supernova, it was a lot of fun trying.  And hopefully, I started to learn techniques that will help me to find and sketch other deep sky objects.

For those that made it to the end of this post, thank you very much for reading all the way through!

Paul

Paul

I write frequently about astrophotography, technology advice, and my other interests like science fiction. I have over 30 years of experience in computer programming, information technology, and project management.

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