Comet C/2020 M3 (ATLAS)

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.

José Joaquín Chambó Bris

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Dial-a-Moon | 2021

What will the Moon look like on any date in 2021? What will it look like on your birthday? Find out at NASA Dial-a-Moon. The example pictured below is for 16 January 2021. Set dates and see views for northern hemisphere and for southern hemisphere readers by following either link. Enter any month and day to see a high definition image. You may leave the universal time (UT) at the default value. If you wish, your local-to-Universal time conversion can be done at this link. Or, type ‘universal time’ into Google. Go back to Dial-a-Moon to enter the UT.

After visiting Dial-a-Moon, scan down that web page for a wealth of additional information about the Moon’s motions and appearance. The images of Dial-a-Moon are made from those of the Lunar Reconnaissance Orbiter (LRO) in low altitude orbit around the Moon since 2009.

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Jupiter-Saturn Conjunction 2020

It has been fun watching the progress of Jupiter and Saturn over the recent months as they neared each other. I started photographing them November 8th. My camera memory setting opens with the same parameters each time for zoom, ISO, f-stop, shutter, etc. I put it on a tripod and got the images at about the same time on 11 dates as indicated in this image. Using Photoshop Elements, I overlaid the new images as layers on top. Saturn’s positions were aligned with a very faint straight line in the image. Jupiter was always placed in the same location for reference.

Jupiter and Saturn Come Together

Have you been watching Jupiter and Saturn in the southwest evening skies soon after sunset? They are getting closer together. By late December they will be nearly in the same position in the sky. This composite image used 4 images I superimposed in the recent two weeks. The thin line shows how close their encounter will be. Keep watching the show.

Moon Occults β Scorpii | 21 Sep 2020

Beta Scorpii (β Scorpii, Beta Sco, β Sco) is in the southern zodiac constellation of Scorpius. It is also labeled as Graffias in this star chart. The Moon passed in front of the star and hid it from view for about an hour. During the hour before occultation, I photographed the Moon and Beta Scorpii at 10 minute intervals using the same zoom and exposure settings. Photoshop Elements was used to merge the series of images showing the progress of the Moon as it neared the star. Disappearance was at about 8:42 pm. Reappearance was 9:40.

Our skies in Iowa have been filtered with smoke and haze from fires in the western states. The Moon and Beta Scorpii were already low in the southwest during the hour before occultation. The Moon was tinted orange. I hoped to also photograph the emergence of Beta Scorpii on the right side of the Moon after occultation. But, the pair was only 5˚ above the horizon. They had disappeared in the hazy atmosphere. During several recent sunsets, the Sun has turned very red-orange and faded from sight before it actually reached the horizon.