Crescent Moon.

Saturday night’s crescent moon. One shot for the daylit crescent, the other for the night side lit by earthshine (with some clouds as a bonus). J. helped with focusing the telephoto lens.

The second shot is a lot noisier than I’d like since I was adjusting levels on the JPEG, but I have the raw file, so maybe I’ll be able to do something better with it. It’ll be a good exercise in learning how to use Darktable.

Overexposed crescent moon, with the  night side faintly visible and a glowing cloud below it.

Google has a new camera mode on its Pixel phones called Night Sight, for handling low-light conditions. The short version is that instead of taking a long exposure, it takes a series of short exposures and stacks them to avoid motion blur from hand movements (plus a lot of additional processing). The long version is fascinating.

My Pixel 2 already takes better low-light photos than I would have expected, but I couldn’t wait to try out the new feature when I learned about it. When the updated Camera app finally hit the Play Store, I had to give it a try.

Two high-rise office buildings at night.

This is adjusted slightly to keep the colors from being too light. And it actually isn’t the best example, as it turns out the nighttime city scene already has enough light for the existing HDR+ mode. I’m going to have to try it on some darker scenes somewhere, but it’s still pretty cool. After the cut I’m posting a version with the phone’s regular mode, and the unaltered Night Sight photo. You can see they’re pretty close, but the Night Sight version picks up a bit more of the color, and it’s a little brighter.

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Venus and Jupiter Conjunction June 30, 2015

On June 30, 2015, Venus and Jupiter lined up very closely in the night sky as seen from Earth, just 0.3 degrees apart — closer than the diameter of the full moon!

The day of the conjunction was muggy and cloudy, and I really didn’t expect to see them at all. To my surprise and relief, it cleared up and cooled off after nightfall.

You really don’t notice how much brighter Venus is than Jupiter until they’re right next to each other. Jupiter is much bigger, so it reflects a lot more sunlight, but it’s also a lot farther away.

Also, that conventional wisdom about how stars twinkle, but planets don’t? Not true. In turbulent air, planets absolutely twinkle.

Venus and Jupiter two days after the conjunction

Two nights later on July 2, I walked outside facing west. The sky near the horizon was still orange, but the two brightest planets were clearly visible against the deepening blue.

And just to show you how fast Venus moves across the sky, here’s the view 10 days before the conjunction, on June 20:

The moon, Venus and Jupiter over Mimi's Cafe

I didn’t have a tripod handy that night, so I used the top of the car, which conveniently lined up with Jupiter and the chimney.

The city of Los Angeles recently finished replacing all of its streetlights with high-efficiency LED lights. They use less power, last longer, and require less maintenance than even the sodium vapor lights — an all-around win. They also cast a slightly bluish light, eliminating the amber look of sodium. But my first thought was that with all that work, they could have taken the opportunity to combat light pollution. The night sky doesn’t seem any darker than it did when we moved up to this area.

Then I took a good look at these LED street lights near work. The new fixtures actually do aim all the light downward, shielding upward leakage. They’re plenty bright from the ground, but from a few stories up, I couldn’t tell which lights were on without looking below them to see whether there was a pool of light on the ground.

So if the streetlights really are leaking less light into the sky, why is it still so hard to see stars to the north? Seriously, I can see Orion clearly most nights, but the Big Dipper is practically impossible to pick out.

  • It was a city project, not a county one. There are plenty of other cities in the area that either haven’t been converting their lights, or have only converted a few.
  • They didn’t actually convert all the streetlights in town, just the standard, boring ones (141,089 of them). Phase 2 is converting decorative street lights.
  • There are lots of other lamps that leak light upward: Parking lots, building lights, private roads. LAX is to the north, and there’s a reason for the phrase “lit up light a landing strip.” There’s also a park nearby with a baseball field; those lights drown out quite a bit when they’re on.
  • The ongoing drought has caused smog levels to climb, making the skies hazier.

Rain lit up by a car headlight.Speaking of the drought, I found myself wondering: How much water would we save if the city did a similar project to replace all the grass along street medians, parking lot boundaries, etc. with drought tolerant native plants? A home lawn at least has a potential use as a gathering place, or a play area. But a little strip of lawn six feet across? What’s the point?

And what do they do with medians out in the high desert, anyway? I remember driving out to Joshua Tree once and noticing in one of the towns along the way that all the houses were built on a standard suburban lot plan with space for a lawn, but that they used it for rock gardens, or native plants, or just left it empty. But I can’t remember what they put along the sides and middles of city streets.

And that gets me to the other article: It was a summary of a study on the vulnerability to climate change in various parts of the region. Most of LA will handle a rise in sea level fine, except for the beaches, Marina del Rey, and San Pedro…but depending on how the climate changes, most of LA would be vulnerable to severe flooding.

In any given decade in California, you can expect at least one drought and at least one winter of heavy rains and flooding. And sometimes those floods can be spectacular. A flash flood in 1825 changed the course of the Los Angeles River (it used to flow into what’s now Marina del Rey). And then there’s the Great Flood of 1862, which covered huge swathes of California and Oregon with water, including all the lowlands of what are now Los Angeles and and Orange County.

So in addition to planning for drought, the region also plans for the occasional flood — unfortunately, by trying to channel all that water out of the way as quickly as possible, because, as the study pointed out, more than 80% of the ground in the area is covered with impermeable surfaces — you know, asphalt, concrete, buildings, etc.

They do have spreading ponds to replenish groundwater from at least part of the storm drain system, but a lot of that water just goes straight into the ocean, and in heavy rains, the ponds get overwhelmed anyway.

It just seems like there ought to be a better way to capture the rain we do get.