Mercury reached its greatest elongation from the Sun in the evenings of April 11-14. We were fortunate to have clear skies during some of those days. At about 8:45 on the 12th, I went out with camera and tripod to see if I could get an image. It was easy to locate a little north of west and about 17˚ above the horizon. Here it is with a few guy wires from a nearby radio tower cutting the corner of the frame.
More about high altitude balloons.
I enjoy checking the air traffic over our area using a site called ADS-B Exchange. Their zoomable map shows all the flights anywhere in the world. We live under the flight paths of many planes crossing the country. That is why we are sometimes called a flyover state. Their map includes the smallest one-runway airstrips scattered around the country which support a lot of single engine planes. We also can watch the helicopter traffic over us carrying patients to the University of Iowa Hospital for care. By clicking on an aircraft symbol, it brings up windows with flight details about the aircraft, how high, direction, speed, etc.
Today, I noticed something unusual on the map. It was not a symbol showing an airplane or helicopter. It was a symbol shaped like a hot air balloon. I’ve seen that symbol only one time before on the map. The info window…
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The spring equinox took place on 20 March 2023 in the afternoon. To celebrate the event, I set up a week-long time exposure with a pinhole camera pointing south from a window of our house. I was able to capture the passage of the Sun across the scene during several cloudless days. The equinox day is visible here as the top dark trace. Go here to see how to make solargraphs.
The photo paper from the pinhole camera was put on the flatbed scanner. Software was used to increase the contrast with this result. Bright sunlight caused dark exposure. Lack of light is white. Part of our house is at the left. The straight edge of the window frame is at the upper right. Tree trunks and branches fill the center. Some neighbor’s houses on another street are across the bottom. The pinhole arrangement gives a distorted fisheye effect.
Software was used to invert this negative image into a positive one for a more familiar appearance.
Wolf-Rayet stars are rare and extremely luminous. They were first discovered in 1867 at the Paris Observatory by Charles Wolf and Georges Rayet. They have masses exceeding 20x that of our Sun and have surface temperatures well over 25,000 Kelvin. Our Sun’s surface is about 6,000 K. Of the billions of stars in the Milky Way galaxy, only a few hundred are known to be Wolf-Rayet stars. Strong winds blow out from their atmosphere and eject material into shells of hot glowing gas surrounding the star. Radiated energy by Wolf-Rayets is many orders of magnitude greater than our Sun. It peaks in the ultraviolet part of the spectrum. Their lives are relatively short.
The James Webb Space Telescope observed Wolf-Rayet 124 in June 2022 using the infrared detector MIRI here seen on the left in purple hues. This recently released image reveals details of internal structure.
The Hubble Space Telescope imaged WR124 back in 1997. It used visible light filters to make the image. They were combined to create this false color version showing details of the gaseous nebula around WR124.
I learned how to overlay and compare the two images using this slider tool available in WordPress. Drag the divider left and right.
I first saw this comparison tool in a post by fellow blogger TextileRanger. She writes Little Wild Streak about nature and Deep in the Heart of Textiles about working with fabrics. Take a look at her posts.
Discovered in March 2022, comet C/2022 E3 (ZTF) caused a stir in the astronomy community. In January and February of 2023, hailed in the news as the Green Comet, it was the subject of numerous media stories. The hype surrounding it’s appearance was rather intense. I looked for it on a few occasions when the weather cleared with hopes of seeing what was being described in articles. I was not impressed with it on either of the two times I saw it. I don’t have the equipment to take long exposures or stack multiple images such as those made by astronomers with better resources. I did enjoy their images and appreciate the skill and talent needed to make them.
Where is the comet now in mid-March? It is positioned to the right of the constellation Orion. It is labeled in green in this desktop planetarium simulation. Each day it moves a little farther down and away from Orion as it fades.
How I See It 