Evening arrived with very clear sky and mild temperature. It was the last night of winter. The International Space Station was due to pass directly overhead from SW to NE. It would pass near the Moon, Mars, Taurus and Orion. The iPad was set with NightCap app to record for about 3 minutes. After recording the scene, I enjoyed some telescope time.
Comet C/2020 M3 (ATLAS) was discovered on 27 June 2020. The acronym ATLAS stands for Asteroid Terrestrial-Impact Last Alert System, based on the Hawaiian islands. Two telescopes of the robotic early warning system are designed to detect smaller near-Earth objects a few weeks to days before they might impact Earth. Since 2017, the scopes survey one quarter of the observable sky four times each clear night. The system is NASA funded and operated by the University of Hawaii.
Orbits near the Earth of objects larger than 1 km are well-known. Most are well documented and predicted years in advance of their close approaches to Earth. Objects down to 140 meters in size are harder to see. It is estimated ⅓ of them have been found. None of those found so far are predicted to threaten Earth in the next century.
Smaller objects less than 140 meters are detected only when they are much closer to Earth. Late discovery means there is the greater potential for a locally catastrophic collision with little warning time if they are on a collision course. ATLAS looks for these smaller objects. Comet C/2020 M3 (ATLAS) was discovered by this system.
The comet became a popular object for amateur astronomers to image. By November 2020 it was nearing the Orion constellation. This image on 6 Nov 2020 was by José J. Chambó at his web site Cometografia.es. I thought it would be interesting to image this comet several times as it passed through Orion.
This video from the NASA Jet Propulsion Lab points out three interesting things for this month. I’m hoping for clear skies on the 18th in order to see the Moon occult Mars.
The brightest star in the night sky is Sirius in the constellation Canis Major to the lower left of Orion. It is bright in the southeast evening sky at this time of year. Follow the three bright stars of Orion’s belt to the lower left and find Sirius.
I wondered if I could see Sirius in the daytime. On two occasions this week, I looked for Sirius with my 15x binoculars. They binoculars are heavy but steadied with my custom support. Both times I was able to see it shining brightly in bright daylight. This is a first for me.
If you are interested in trying this yourself, here are some details. Sunset is just after 7:15 pm locally. The time of viewing Sirius was about 6:15 pm CDT with very clear sky. It was at 150˚ azimuth (east is 90˚ south is 180˚) and was about 26˚ altitude. I have a small app on my Android phone called Protractor that helped determine the altitude. Give it a try.
Two days ago, the ISS passed over me here in eastern Iowa. I posted a couple of pictures in this short post. This morning, it happened again. The ISS was just below Orion. He had to jump up to avoid getting hit in the ankles.
They were separated enough so two images were needed. First, I got the ISS with Orion’s lower parts in the frame. Second, I got Orion. The two images were stitched into this one. Image details for the interested photographers is below.
|Model||FinePix S602 ZOOM|
|White Balance||Tungsten Bulb|
In addition to ISS and Orion, the Moon was a thin crescent toward the east. The earth glow was very nice. Here is an interesting calendar of Moon visibility.