In the evening of 12 May 2021 at 8:41pm, the waxing Moon was near Venus low in the western sky. Clear conditions allowed a fine binocular view. Without them, I would not have seen the Moon’s very thin crescent.
If the sky is clear the evening of 13 May, look again for the Moon in the west. It will be to the left of Mercury this time. Not quite as close as it was to Venus. Binoculars will help. The Moon will be illuminated 4.34% and easier to find.
The Hubble Space Telescope was launched into space 24 April 1990. Astronomers recently aimed Hubble at one of the brightest known stars, AG Carinae, in the constellation Carina. This luminous blue variable lies about 20,000 lt-yr from Earth. It exploded about 10,000 yrs ago. The nebula surrounding the star contains the equivalent of about 15 times the mass of our Sun. The star has about 55 times the mass of our Sun. Scientists from NASA, ESA, and STScI made this color image by combining four color-filtered greyscale images listed at the left.
The following video was released by NASA Goddard to celebrate this occasion. It lasts about 5 minutes.
In April 2019, astronomers with the Event Horizon Telescope EHT released the most detailed image of the region near a black hole in the large elliptical galaxy M87. This image was the first view inside the core of a galaxy showing the extremely energetic spinning disc, or donut, of material and radiation surrounding the invisible black hole at the center. Material falling into the black hole disappears within this horizon. Not even light can escape. This black hole is about 55 million light-years from us and has a mass 6.5 million times that of our Sun.
We are not seeing the black hole. We are aware of the absence of anything visible in the center. That is where the black hole is located. I invite you to read my previous non-technical post about this story.
In April 2021, new findings from multiple radio, optical, X-ray, and gamma-ray telescopes were shared revealing greater detail about the broader surroundings and processes taking place in the vicinity of galaxy M87. The telescopes are ground based and some are space based. They observed in wavelengths from long radio waves of many meters, the more familiar shorter waves of the optical spectrum, and in extremely short X-ray and gamma-ray wavelengths. Such broad coverage will give scientists greater insights into the dynamics near black holes and aid their understanding of Einstein’s General Theory of Relativity.
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.
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.