Trees and Planets and Light Pollution

August 20th, 2021, 12:05 a.m. local time

I took this picture with my iPhone quickly as I was packing up my telescope on Jupiter’s opposition night (more on this in a future post).  This image is largely unremarkable but I noticed in hindsight it reveals much of my stargazing circumstance.

  • In my blog posts I frequently mention the trees blocking my views to the South.  Here you see the westernmost tall cottonwoods of that line.
  • Jupiter, Saturn (faint), and the Moon appear to be in elliptic line, but they are really not.  Each has its own elliptic, notably Jupiter’s is higher that Saturn’s from this vantage.  Jupiter clears the trees so I can take pictures much earlier than Saturn, which has to exit the tree line fully for telescope views.
  • You can see a neighbor’s absurd light pollution bubble.  I have planted my own small trees, not shown here, that do a respectable job blocking the light from my deck.  It’s just the angle of my iPhone shot that happened to catch what I now largely ignore.
  • See that house side at the bottom that looks like it is painted two colors?  The light side is actually streetlight reflection, which has gotten worse in the past year as the traditional bulbs have been replaced by grated high-powered LEDs.

The moral of this story is that trees are a blessing and a curse for stargazing.  While they obscure parts of the sky, they also defend against light pollution.  Trees are in sum a great net benefit for observing the night sky.


Pictures taken with my iPhone and minorly post-processed in PaintShop Pro.

Lazy Late Summer

Taken on an Illinois trail August 18th, 2020.

Greetings.  It’s been a while since I posted, so wanted to do a “check in” post.  I haven’t done much astronomy over the past month, for various reasons which could be considered excuses, but I won’t call them that.  I could itemize the various new light pollution issues in my area that have grated me, but the reality is I already lived in a one of worst polluted spots on Earth.  The residual haze from the western United States forest fires notwithstanding, I hope to get back to sky viewing soon, and certainly in time for the approaching Mars opposition.

The true limiting factor over the past month was some sort of injury to my wrist.  Around the time I took the above picture in August, I did something to my dominant left wrist and I couldn’t put even simple strains on it, let alone try lifting my Dobsonian to take it outside.  And so I restricted my activities to only those necessary.  Fortunately within the last week it seems to be back to normal, though I continue to remain careful and will give it another week-ish before I lift the big telescope again.

Part of me believes this is the “downer” time, after the mid-Summer Jupiter and Saturn oppositions plus the bonus of the Neowise comet.  But things are looking up, as they always do in time.

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.

Click to see full-sized image.

(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):

Click to see full-sized image.

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:

Click for full-sized image.

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.

Click for full-sized image.

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.

Click for full-sized image.

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.

Click for full-sized image.

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:

Click for full-sized image.

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:

Click for full-sized sketch.

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.

Click for full-sized sketch.

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:

Click for full-sized 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:

Click for full-sized sketch.

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:

Click for full-sized image.

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.

Click for full-sized sketch.

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:

Click for full-sized sketch.

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!

Early Morning Glimpse of Saturn and Jupiter

Objects in the early morning sky. Left to right: Saturn, Jupiter, part of the constellation Sagittarius.

June 16th, 2020, 03:22 a.m. local time

I happened to be up early mid-morning and decided to check on Jupiter and Saturn.  I knew from my observations last week that they should have been almost due South, and my direct observation confirmed this.  The above picture was hastily taken with my phone.  Interestingly, this is the stock iPhone camera app, versus NightCap.  Normally, NightCap gives better ad hoc photos of the sky, in my experience, but this time, NightCap’s TIFFs were too dark.

Jupiter is the big bright object near center.  Slightly above and to Jupiter’s left (from our vantage) is Saturn.  You can also see sloping towards the right some of the brighter stars in the constellation Sagittarius.

This picture also emphasizes how bad my location’s light pollution is.  That glow towards horizon is not the Zodiac lights, but the overabundance of artificial illumination even after 3 a.m.

Edit: Zooming into the image, I noticed a star was captured above and slightly left of Saturn.  According to Stellarium, that is the (double) star Dahib, brightest star in the constellation Capricornus.

Unidentified flying objects in night sky? What were these?

Click for full-sized image.

April 26th, 2020, 9:10 p.m. local time

Tonight I saw something truly bizarre.  On this clear Spring night, I took my camera out to take pictures of the Moon and Venus together, around 9 p.m. local time.  I started with a wide lens to get both objects together, then quickly switched to my long 300mm lens for a closeup of the Moon in its early Crescent phase.

I had planned to take a number of image sets while refining the focus.  In the middle of this exercise, above the Moon and Venus, and still higher than Castor and Pollux of Gemini above them, I saw appear a trail of light points moving from W-NW to SW, right to left from my vantage and on a gradual incline towards the South.  They were in perfect unison motion and if I had to guess, there were about 30 of them.  They were in no uniform pattern, with some bunched and others alone.  They moved at about the speed of a typical visible satellite, stretching and moving from above Gemini and then disappearing somewhere past Regulus.

I knew I had to act quickly to photograph them, as they were moving fast and I didn’t know how long they would be visible or if more were coming.  Unfortunately, I had my long lens on the camera, so the field of view was far too narrow to appreciate the size and spectacle of this train of moving light points.

If I had had my wider lens on from just a few minutes prior, I know I would have easily gotten a much better perspective shot.  Instead, my best snap of about five is show here, with the light points artificially enhanced so you can see the line.  It’s important to note that this grouping is just a small fraction of the entire visible line I saw high above.

I have no idea what these were.  My first thought was drones, but they were obviously far too high and their motion was akin to any random satellite, except of course that there were dozens of them, moving in a line.  My only other idea was some sort of debris just above the atmosphere that was in perfect position to reflect the light of the Sun (which had set over an hour prior).

The only event I can remotely compare this to was when I saw the ISS and a Space Shuttle, some 15-20 years ago, fly over in perfect unison.  But they were only two points of light, and if I remember, they were more side-by-side, whereas these lights tonight were in a straight line.

Do you have any idea what these light points could have been?  Have you ever seen anything similar?

Edit: It appears I saw the SpaceX satellites.  See this post and its accompanying video:

How To See A ‘Starlink Train’ From Your Home This Week As SpaceX Satellites Swarm The Night Sky

The Stark Contrast of Old and New Bulbs – Light Pollution

I have tried to swear off further posts on light pollution, feeling my prior writings suffice for the time being.  However, this week I walked into an empirical example that I simply could not ignore.

While getting off the train one night, I was on a section of platform that had recently been renovated.  It had received a new walking surface, and the lamp light bulbs had been replaced with newer LEDs.  Within a few paces of one of these lamps with the new bulb was a lamp with an older bulb, closer to the parking lot.  I assumed this was a sodium bulb, or at least it exhibited the characteristics of the old sodiums.

I was able to take a picture of both lamps from the same location, posted here above.  On the left is the old sodium (-like) bulb, and on the right is the new LED bulb.  From my vantage point that evening I quickly observed differences in experiences from being under the light of both.

First, both lights were overall too bright, and they were unshielded.  You can see how the lamp design does very little to restrict the light towards its intended targets.  While the light mostly heads towards the ground, it disperses in all directions, including up.  There are probably at least a hundred of these lights throughout the train station area.

Aside from these issues, all else being equal, here is what I observed, first on the sodium/older bulb:

  • Had a softer glow.  I could look in the direction of the bulb and not feel irritated.
  • Does a far better job of bathing and immersing its surroundings in light.  The entire area around the lamp definitely looked “lit up”.
  • For night, it was relatively easy to make out all the objects around the lamp.
  • The color of the lamp distorts the natural color of the surroundings.

For the new LED bulb:

  • Projected a very harsh brightness.  Cannot comfortably look in the direction of the bulb for very long.
  • The ground around the lamp looked very dark compared to the area around the sodium bulb.  I could definitely see everything but I also felt like my eyes were straining to see the area.
  • The color was more neutral/white than the sodium, but this was offset by the weaker luminous feel.
  • In my peripheral vision, the bulb was distracting.  I’ve noticed this while driving, too.

Any energy savings of these newer LED bulbs are offset and nullified by their degraded functionality.  They seem to be very good at pinpoint brightness but are unable to luminate their surroundings effectively.  On top of that, they are grating on the eyes.

Ultimately, any bulbs (except blues) should be fine for nighttime function so long as they are properly shielded.  I have seen and walked under “dark sky” lights and they are fine for their intended purpose.  These accompanied with motion sensors and smart electronics would go a very long way towards helping reduce light pollution.

Thirty Theses on Light Pollution, 2020 Edition


I have scarcely written about light pollution since my first edition of this list two years ago.  That’s in part because the original theses covered everything I wish to say on the topic, for now.  This update is very minor in form, with just a few small changes throughout.

Light pollution unfortunately continues unabated, with the threat of ever newer and bizarrer ways concocted to ruin our common view of Space.

There is no obvious or quick solution.  I hope this list helps to frame the matter for you, and perhaps will assist you in discussing the topic with others.

(I) Light Pollution is pollution.

(II) Light Pollution is possibly the least-understood and least-recognized form of pollution.

(III) Most people do not know what Light Pollution is.

(IV) Light Pollution distorts the Earth’s natural night sky.

(V) Light Pollution’s distortion on the Earth’s night sky, by extension, distorts the Earth’s natural environments.

(VI) Science continues to accumulate evidence of the environmental impacts of Light Pollution.

(VII) The scientific evidence to-date is insufficient to awaken the general population to the existence of Light Pollution and its impact on Earth’s environments.

(VIII) Light Pollution is a recent phenomenon in human history.

(IX) Light Pollution is artificial.

(X) Moonlight is not Light Pollution, but part of the Earth’s natural environment that evolved over billions of years.

(XI) Humans and most non-nocturnal animals have difficulty sleeping under artificial light, preferring the dark of night.

(XII) Light Pollution directly inhibits terrestrial stargazing and other astronomical pursuits.

(XIII) Light Pollution lessens children’s curiosity about the night sky, stunting their desire to learn and imagine.

(XIV) Light Pollution severs our visual conduit of the cosmos from Earth.

(XV) The intended direction of nearly all artificial night lighting is down.

(XVI) Most artificial light illuminates in all directions (down, up, sides).

(XVII) Artificial light that illuminates outside of its intended range wastes energy.

(XVIII) Artificial light that illuminates outside of its intended range may be an encroachment onto surrounding lands and properties.

(XIX) Light Pollution is caused by artificial illumination of the night sky.

(XX) Light Pollution will never be eliminated completely from civilized locations, but it can be greatly mitigated.

(XXI) Light Pollution can be reduced with no impact to quality of life and security.

(XXII) Light Pollution can be significantly reduced by shielding all outdoor lighting to focus illumination on the intended ground target.

(XXIII) Shielded lights make nighttime visibility easier by reducing harsh bulb glare.

(XXIV) Light Pollution can be significantly reduced through the use of timers and motion sensors.

(XXV) All commercial and home decorative lighting should point downward with bulbs or diodes shielded on their sides.

(XXVI) Most Light Pollution comes from street lights.

(XXVII) Newer LED lights contribute far more to Light Pollution than the older, traditional sodium streetlamps.  This is because newer LED diodes blast light across almost the entire visible light spectrum, whereas the older sodium lamps emitted light at a very narrow yellow band within the visible spectrum.

(XXVIII) Newer LED lights are OK for outdoors but should be low-intensity, shielded, and ideally triggered by motion sensors.

(XXIX) Blue light is the worst light for outdoors because the Earth’s atmosphere absorbs blue spectrum light the easiest.  Think of the daytime blue sky!

(XXX) Images from space of the Earth’s ground illuminated at night were once evidence of progress, but now should be viewed as evidence of our collective ignorance about Light Pollution and not understanding how to lessen its impacts on the Earth’s environments.

What Do You See?

I took this image of Chicago after dusk on December 20th last year.  What do you see?

Some may say they see a city alive, from the skyscrapers to lakefront to the bustling streets that run through Chicago’s commercial, industrial, and residential zones.

Personally, I see photons.  Lots and lots of stray protons, all of them moving up.  Beyond the few markers intended for aviation safety, the sources of these photons are illuminating spaces beyond their intended targets.

What do you see?

Thirty Theses on Light Pollution, 2017

(I) Light Pollution is pollution.

(II) Light Pollution is among the least-understood and least-recognized forms of pollution.

(III) Most people do not know what Light Pollution is.

(IV) Light Pollution distorts the Earth’s natural night sky.

(V) Light Pollution’s distortion on the Earth’s night sky, by extension, distorts the Earth’s natural environments.

(VI) Science has accumulated sparse evidence of the environmental impacts of Light Pollution.

(VII) The accumulated scientific evidence to-date is insufficient to awaken the general population to the existence of Light Pollution and its impact on Earth’s environments.

(VIII) Light Pollution is a recent phenomenon in human history.

(IX) Light Pollution is artificial.

(X) Moonlight is not Light Pollution, but part of the Earth’s natural environment that evolved over billions of years.

(XI) Humans and most non-nocturnal animals have difficulty sleeping under artificial light, preferring the dark of night.

(XII) Light Pollution directly inhibits terrestrial stargazing and other astronomical pursuits.

(XIII) Light Pollution lessens children’s curiosity about the night sky, stunting their desire to learn and imagine.

(XIV) Light Pollution severs mankind’s prime connection for wondering about the cosmos.

(XV) The intended direction of nearly all artificial night lighting is down.

(XVI) Most artificial light illuminates in all directions (down, up, sides).

(XVII) Artificial light that illuminates outside of its intended range wastes energy.

(XVIII) Artificial light that illuminates outside of its intended range may be an encroachment onto surrounding lands and properties.

(XIX) Light Pollution is caused by artificial illumination of the night sky.

(XX) Light Pollution will never be eliminated completely from civilized locations, but it can be greatly mitigated.

(XXI) Light Pollution can be reduced with no impact to quality of life and security.

(XXII) Light Pollution can be significantly reduced by shielding all outdoor lighting to focus illumination on the intended ground target.

(XXIII) Shielded lights make nighttime visibility easier by reducing harsh bulb glare.

(XXIV) Light Pollution can be significantly reduced through the use of timers and motion sensors.

(XXV) All commercial and home decorative lighting should point downward with bulbs or diodes shielded on their sides.

(XXVI) Most Light Pollution comes from street lights.

(XXVII) Newer LED lights contribute far more to Light Pollution than the older, traditional sodium streetlamps.  This is because newer LED diodes blast light across almost the entire visible light spectrum, whereas the older sodium lamps emitted light at a very narrow yellow band within the visible spectrum.

(XXVIII) Newer LED lights are OK for outdoors but should be low-intensity, shielded, and ideally triggered by motion sensors.

(XXIX) Blue light is the worst light for outdoors because the Earth’s atmosphere absorbs blue spectrum light the easiest.  Think of the daytime blue sky!

(XXX) Images from space of the Earth’s ground illuminated at night were once evidence of progress, but now should be viewed as evidence of our collective ignorance about Light Pollution and not understanding how to lessen its impacts on the Earth’s environments.

I don’t normally concluded my posts with “please share/retweet/reblog/etc.” requests, but if you feel better informed of and aware on the topic of light pollution, please forward this to your friends and neighbors.  Spreading knowledge about light pollution is the best strategy for eventually solving the problem!