Saturday, April 25, 2015

Lighting in Wildomar: Glarebombs slip though the cracks

A new building in Wildomar has installed lighting the violates Wildomar's municipal code and creates a safety hazard near a public school.


The Wildomar City Council has taken action on lighting violations in the past, and so this presents another problem-solving opportunity. It may be difficult to correct this building, as so much lighting has already been installed. The parking lot lighting needs to be of a lower color temperature (no higher that 3500 k). The wall-mounted glare bombs are useless, and need to removed or replaced. Even the decorative post lamps fail because they aren't adequately shielded.

These glare bombs are on Bundy Canyon Road across from Elsinore High School, a route that is frequently tread by youth showing poor judgment when crossing roads. The area is fairly dark, but now a motorist will have to see the students' dark silhouettes against the glare from the building.

This is how a community loses its dark sky.


jg

Sunday, April 5, 2015

Lunar Eclipse, 3 April 2015

I've been in the desert for a couple days chasing the eclipse but caught a few other gems as well. Photo 1 is the eclipse, which makes me want to draw a distinction between total visual and total photographic. This eclipse skirted the edge of the earth's inner shadow and though it appeared completely in shadow, none of my photos show a completely shadowed moon.




These photos show one of those scenes not seen in nature, except when it is seen in nature. You will never see a setting crescent moon with the lit side of the crescent up, unless of course, unless of course, it's a partial eclipse that is setting with the shadow conveniently on the bottom side. 






Below is a sun pillar that greeted me on sunrise (the vertical column about the point of sunrise). 




Last is the kind of thing perhaps only I like: a contrail being replaced by it's own shadow.



jg


Saturday, March 21, 2015

Volcanic Mayhem

My latest science illustration project is this diagram of death blows from a volcanic phenomenon known as a Large Igneous Province. The diagram is a contribution to a two-part post on the subject by John Mason, writing for Skeptical Science. 


Links to the post:


jg

Thursday, March 19, 2015

Nova in Sagittarius

A nova has appeared this week in Sagittarius. This time of year, Sagittarius is in low in the south between 5:00 and 6:00 am. I made a video comparing Sagittarius as seen on March 18 with Sagittarius seen last year.



Two years ago I photographed a nova in Delphinius. My regret is not following up over the year to observe the fading of the nova. Therefore, I have no personal estimate of how long a nova will last. I know it's not hard to research, but I prefer to observe first, a bit like reading a book before watching the movie.

Sagittarius is a summer constellation, so I will have a good six months to observe the nova's decline.

jg

Monday, March 2, 2015

An unusual fascination with pinhole projections and other optical analogies from my time in prism

I created a new astronomy presentation last weekend. I'll be presenting it to my club, the Temecula Valley Astronomers, tonight at 7:00 at the Temecula Library on Pauba Road -- nothing like the last minute, as working on it this weekend suggests, but it's based on observations of pinhole projections, also called the camera obscura, that I've been interested in for many years.

I believe the pinhole projection provides all the information to intuitively understand how telescopes work and how focal ratio affects depth of field:



To complete the analogy, I add prisms, which lead me to contemplating William Herschel's discovery of infrared. To resolve a discrepancy, I examine black body radiation curves, which leads me to understanding the green house effect, and for the first time I think I can explain why nearly every illustration of the greenhouse effect is wrong by over simplification.

I'd write more, but it's, as I said, last minute and I have preparation to do.

My presentation (which severely lacks annotations) can be found at this location:

http://www.brightstarstemeculavalley.org/pages/presentations.html


jg

Sunday, February 22, 2015

Hole punch clouds

Shortly after sunset on Feb. 19 I saw what looked like a hole-punch cloud, also called a fall streak hole. It looked a bit like a giant space amoeba from Star Trek:





OK. Maybe a lot like one.

I understand these are caused by a domino-like effect where super-cooled water vapor needs a nudge to create a cascading condensation that then falls out of the cloud. One possibility for the source of the nudge is a passing airplane.
I've seen these before and I assumed updrafts from our nearby mountains were the cause, but I don't know.
At least one of my pictures confirms the hole punch occurred near the flight path of planes. The bright line in this photo is a plane:

However, my pet theory that the mountains are creating updrafts that trigger the condensation suggests that there would be more hole punches to coincide with the few peaks in the area, as shown in this photo from a couple years earlier:
Hole punch clouds above the mountains on my western horizon


I looked around for others and did find one, though it was less impressive:


Though less impressive, it did look a little like a giant rabbit in the sky (on its back), something I've been seeing a bit of recently and shared with the Orange County Astronomers last week:

Multiple hole punches does not eliminate planes as the source, so the cause in my region is not settled.

As the hole punch drift east, the sky was dark enough to bring out a few stars: 


Other hole punch clouds:




jg

Saturday, February 14, 2015

What's Up February 2015

A better blogger would be more punctual in sharing his projects. I continue to create presentations but rarely find time to share the content on the web. I recently presented a What's Up on the night sky to the Orange County Astronomers, which I'll share here.

Before looking at the stars, one has to look through the atmosphere, so I always share any recent observations of parhelia, that is, sun and atmosphere effects. The best example I've had recently are these iridescent clouds from late December:

As this effect occurs close the sun, please be careful to avoid looking at the sun.

And, if you start to see things, you've looked too long:

Giant multi-colored sky rodent

Turning to the night sky, here are the locations of planets, constellations, and areas I chose to discuss:
Venus (yellow) and Mars (red) linger in the west; Jupiter rises in the east. The winter milky way passing over head in the evening, but is visible only from a dark location.

Rectangles represent areas that I photographed and share below.

Comet Lovejoy is in the northwestern sky moving from Andromeda to Cassiopeia.

The green arrow shows the path of comet Lovejoy.

Along with Lovejoy, there are many other fine objects for the telescope or binoculars. Now is a good time to look from a dark location. Soon, these objects will plunge into the western horizon.


Note that on Feb 20, Lovejoy will pass near M76. The two will be worth a look through the telescope.

Here's a photo of comet Lovejoy from this week:


As a side note, while taking the above photo I captured an enjoyable coincidence:


This photo is a plane passing in front of M31. I was alarmed when I saw the photo on my camera's LCD display, for I was sure the trail was an airplane, but I hadn't identified the source of the sudden brightness. When viewing the photo on a computer, it was obvious that the flash was the Andromeda Galaxy (M31) oriented so that the long axis of its oval shape aligned with the path of the plane. Normally I don't boast of my photos of the flight path out of LAX, but this one is an exception.

In the east we see the Big Dipper, also "Ursa Major, the Big Bear" rising:


Lacking a good starry photo of the rising, leading edge of Ursa Major, I used this one taken from June of 2014 from a darker location.

Of course, when flipping a western photo to make it look like an eastern one, keep in mind the trees or any other incongruities:

A little cropping and diagramming shows the location of some worthwhile deep-sky targets for this time of year:


Each year I forget to spend quality time observing M81, M82, M108 and M97, which all require a telescope to see. The reason is that these are rising in February, when it's cold, and by late spring when I am out at a dark location, these objects are already setting in the western sky glow or lost in the trees at Palomar Observatory Campground. This year, my goal is to catch them rising, and take some photos to help me remember their qualities and locations. If I fail, there's always next year: unlike a beautiful open space on Earth, you don't have to see it before someone changes it. E.g., no one is going to enter Ursa Major with earth movers and develop it. So, it's safe to fall in love with a part of the sky, knowing it's never going to go away for good. (I once mentioned this to my former County Supervisor, who joked if there was a way to make money developing the constellations, developers would try anyway.)

The darkest part of the sky, regardless of your location, is overhead. Now, the view overhead reveals Auriga, the Charioteer:


Auriga offers some star clusters that can be found in binoculars.

However, these clusters, such as M35, are best viewed in a telescope:

No winter sky presentation is complete without calling out the location of the best nebula in the night sky, visible high in the south in binoculars as well as the telescope:


Find Orion in the south, then find its belt of three aligned stars. From there, look below the belt to the region named as Orion's sword. This region is a star cluster and nebula. Some people will see this with the naked eye, but all will see it well with binoculars. 

Back to the planets, there is a delightful conjunction of Venus, Mars, and the crescent moon on Feb 20. Also, Jupiter is falling into an alignment in which the orbits of its moons can be seen edge on, making the moons pass in front of each other and making for eclipses:

Imagine Jupiter moving through it's orbit carrying it's moons with it. Our view of it's tilt will change from year to year, This year, the view appears edge on.

I recorded a similar series of eclipses 12 years ago and had the wits to document my observations. The following illustration shows my pictures of the moon Io being occulted by the shadow of the moon Ganymede.

Happy star gazing, and local viewers may want to plan to attend the Wildomar star party at Marna O'Brien Park on April 25, 2015.

jg