The first eclipse season of 2022 will reach its peak this coming weekend, with a spectacular total lunar eclipse taking place on Sunday night until Monday morning.
The eclipse will take place in whole South America and most of North America, while Alaska and western Canada will see totality underway at moonrise, and western Europe will see the reverse at moonset near dawn.
The circumstances for Sunday night''''s eclipse
In what''s called asyzygy, the nodes where the Moon''s orbit crosses the ecliptic are tilted just over five degrees relative to the ecliptic; otherwise, we''d see solar and lunar eclipses every synodic month (29.5 days).
An eclipse season occurs when the nodes are near the Sun-Earth line.
This year, this first season of 2022 was grouped by the April 30 partial solar eclipse, followed by this coming weekend''s lunar eclipse.
At the Moon''s average distance from the Earth, the Earth''s dark inner umbral shadow is about three times the diameter of the Moon (1.5 degrees across). During an eclipse, there is no special gear required.
Shadows have a more subtle outer edge, inside which the light source is partially visible. From the Earthward surface of the Moon, you''d see a partial solar eclipse during the penumbral phases and a total solar eclipse during the umbral stage.
In 1967, NASA''s Surveyor 3 successfully recovered an image of a solar eclipse from the Moon:
Images of a solar eclipse from the Moon (it was a total lunar eclipse on Earth) with a television camera aboard NASA''s Surveyor III lander on April 24, 1967. pic.twitter.com/nPryJl6Xnm
Human eyes may be able to repeat this feat as the Artemis missions return crew to the lunar surface, starting mid-decade.
The moon''s color will not be revealed in any way until Sunday night, as it''s about mid-way scuffled in the penumbra around 10:00 PM Eastern Time (EDT) (2:00 UT).
The Moon will then form a light tea-colored hue. Around 2:20 UT, you will notice a shading on the eastern limb of the Moon, as it begins to circle the umbra and the partial stages.
Totality is the key stage of this eclipse, which will last for one hour, 24 minutes, and 53 seconds.Totality runs from 3:29 UT/11:29 PM EDT to 4:54 UT/12:54 PM EDT, making it the fifth largest lunar eclipse for the first quarter of the 21stcentury.
This is not a ''Super Blood Moon Eclipse,'' though no doubt folks will consider it as such. On May 17, the eclipse occurred about a day and a half before lunar perigee at 15:24 UT, when the Moon is 360,300 kilometers distant.
A lunar eclipse is a fine stately event, requiring no special optical equipment, although a small telescope or binoculars can certainly enhance the view. Although photographing a total lunar eclipse is also quite straightforward to do, otherwise you''ll want to use a focal length of at least 200mm otherwise, the Moon will appear as only a silvery-white dot.
Make sure to shoot in manual mode, and be prepared to switch from a slow 1/100th of a second during the partial phases, to a slow 1 - 4" exposure during totality.
Photographers may snag totality along with foreground objects on their sites beforehand, and make sure you have a generous baseline between yourself and the chosen target in front of the Moon: a building or statue must be up to a kilometer away.
None more red
Not all lunar eclipses are created equal.
The shape of the "Blood Moon" can differ quite a bit during totality, from a bright saffron yellow disk with a blue-tinged limb to a dark brick red. As was the case during the December 1992 lunar eclipse, the Moon was known to nearlydisappear from view during totality, just after Mount Pinatubo''s eruption in the Philippines.
TheDanjon Scalerunning (bright) is a term used to describe the color and intensity of the Moon as it appears during totality.
Two factors determine this value: One is how central the Moon passes through the umbra during a brief (just under five minute) eclipse on the night of 4 April 2015, putting the Moon in a huge debate over the estimated versus actual size of the Earth''s shadow at the Moon''s distance.
The second factor is the amount of dust and aerosols currently suspended in the Earth''s atmosphere, and the red you''re seeing during totality is due to the sunlight from a tenth of sunrises and sunsets, which is then filtered into the Earth''s shadow from around the surface of the planet.
In the last year, volcanic eruptions in Tonga, forest fires, and dust storms around the world may add to this environmental atmospheric load, resulting in a somewhat dark total lunar eclipse.
Tales of the saros
All eclipses are part of the asaros series, or a set of eclipses will almost certainly be spaced just over 18 years apart. This works because 223 lunations almost equals 18 years, 11 days, and 8 hours (just shy of 17 minutes, in fact) with each successive eclipse in the same saros series shifting about 120 degrees westward.
The Babylonians also believed in the saros cycle, which they used to forecast future eclipses. Asian nations include the Greeks, who also knew about the saros cycle of eclipses, and built this knowledge into the famous Antikythera technique used to forecast future eclipses.
Saroses evolve over time, beginning as shallow penumbrals, then becoming central total eclipses before falling. This weekend''s eclipse is member 34 of the 72 eclipses inlunar saros series 131.
This series began waaaay back on 10 May 1427, and will begin producing its last total lunar eclipse on 3 September 2022, before ending on (mark your calendars) 7 July 2707 AD.
During a lunar eclipse, there are a few fun activities to do. One is a long-standing effort to time when specific lunar cratersenter the umbra in an effort to improve the Earth''s established diameter.
Another technique is to attempt to measure your longitude during an eclipse. This technique was used by mariners such as Captain James Cook and (possibly) Columbus.
It works because the eclipse gives you a good one-time ''time hack,'' which allows the observer to determine the position of the eclipsed Moon in the sky, versus a known prediction from a table made for a land-based observatory.
It''s also worthwhile to keep an eye on and reviewing photographs and video for meteors striking the eclipsed Moon. Just an event during the January 2019 eclipseand sent lots of us scrambling, to see if we also caught the flash on the lunar limb.
There is a possibility that aHerculid meteor outburst courtesy of anasteroid (nee comet?) 2006 GY2 might be active this weekend, so it''s a good idea to keep an eye on any further misinformation.
Transits and occultations
During the eclipse, be sure to be vigilant to what happens in front of (and behind) the eclipsed Moon. Although we do not have a favorable ISS transit for the United States during the eclipse, we do have a transit of China''s new Tiangong Space Station on the ground around the start of totality:
Finally, one easy task to try to see during a total lunar eclipse is to nab theelusiveselenelion or seeing the completely eclipsed Moon and rising Sun above the horizon at the same time. This works because the umbra of the Earth is bigger than the Moon, and the Earth''s atmosphere destroys light from both.
For this unique astro-athletic feat, you''ll need high ground and a clear horizon. For Sunday night and Sunday morning''s eclipse, there are two contact zones (see the world eclipse map earlier in this article). These swaths cover western Canada at sunset, and Iceland, the United Kingdom, France, and Central Africa.
This weekend, we''ll keep an eye on weather forecasts. Keep in mind, you''d don''t need a crystal-clear sky to witness a lunar eclipse, but a good clear view of the Moon.
For Sunday night, a projected cloud cover percentage for the CONUS (NOAA)
Are you covered by the Virtual Telescope Project, where the astronomer Gianluca Masi will host the total lunar eclipse starting on May 15 at 2:15 UT/10:15 PM EDT.
Don''t miss the first full lunar eclipse of 2022!
This article was originally published by Universe Today. Read the original article.