Home Science & Technology Our complete guide to a total lunar eclipse this weekend

Our complete guide to a total lunar eclipse this weekend


Don’t miss one of the major astronomical events of 2022: the total lunar eclipse on Sunday.

The The first eclipse season is 2022 reaches its climax this coming weekend, with a beautiful full lunar eclipse that will occur on the night from Sunday to Monday morning. All of South America and much of North America will see a total eclipse, while Alaska and western Canada will see a total eclipse at moonrise, and Western Europe will see the opposite at sunset at dawn.

Circumstances of the eclipse on Sunday

Eclipses occur when the nodes where the Moon’s orbit intersects the ecliptic (the plane delineated by the Earth’s orbit) align with the Sun and Earth, in what is known as syzygy. The orbit of the Moon is tilted just over five degrees relative to the ecliptic – otherwise we would see solar and lunar eclipses every synodic month (29.5 days). When the nodes are near the Sun-Earth line, the eclipse season comes. For example, this first season of 2022 was put in parentheses April 30th partial solar eclipseand then a lunar eclipse will occur over the coming weekend.

Circumstances of Sunday evening

The dark inner shadow of the Earth’s umbrella is about three times the diameter of the Moon (1.5 degrees in diameter) at the average distance of the Moon from the Earth. You can really see the curve of the Earth’s spherical shadow that crosses the moon during an eclipse, no special equipment is required.

Shadows also have a thinner penumbra outer edge, inside which is partially visible light source. From the Earth’s surface you will see a partial solar eclipse during partial shade and a total solar eclipse in the solar cover stage. NASA’s Surveyor 3 did manage to capture an image of a solar eclipse from the moon in 1967:

A solar eclipse … visible from the moon. Author: NASA / Surveyor 3

Perhaps human eyes could repeat this feat when the Artemis mission returned the crew to the moon’s surface beginning in the middle of the decade.

An eclipse on Sunday night … as seen from the moon. Credit: Stellarium.

Don’t expect too noticeable changes in the color of Sunday moonlight until it plunges into partial shade near the middle 22:00 Eastern Time (EDT) / 14:00 World Time (UT). Then the moon will acquire a light tea hue. Around 2:20 UT you will notice shading on the eastern limb of the Moon as it approaches the shadow and the partial stage begins.

The timing and circumstances of the visibility for Sunday’s eclipse. Credit: NASA / GSFC / Annotations: Dave Dickinson

The key is full time, and it will be long for this eclipse, which lasts 1 hour 24 minutes and 53 seconds. The aggregate runs from 3:29 UT / 23: 29 EDT to 4:54 UT / 12: 54 pm EDTmaking it the 5th longest lunar eclipse first quarter of 21street century.

It’s not “Super Bloody Moon Eclipse …” though, no doubt people will try to expose it as such. In fact, the eclipse occurs about a day and a half before the lunar period of May 17th at 15:24 UT when the Moon is at a distance of 360 300 kilometers.

Sky map
A scene of the sky from Norfolk, Virginia, in the middle. Credit: Stellarium.

A lunar eclipse is a wonderful celebration that does not require special optical equipment … although a small telescope or binoculars can definitely improve your view. To photograph a total lunar eclipse is also quite simple, although you want to use a focal length of at least 200 mm – otherwise the moon will look no more than a silvery-white dot. Also, be sure to shoot manually and be prepared to reduce exposure from a fast 1/100 second during partial phases to a slow exposure of 1-4 inches throughout.

From January 31, 2018: “Eclipse of the Windmill”. Copyright and copyright: Starguy Mark (@SSA_Mark)

Areas that see the whole point during the rising and setting of the moon also give photographers the opportunity to capture everything along with foreground objects. Be sure to study your site in advance and plan to have a generous baseline between you and your chosen target before the moon: you will need to be within a mile to make the building or statue seem the size of the moon.

No more Red

Not all total lunar eclipses are created equal. The color of the “Bloody Moon” can change quite a lot throughout the period, from a bright saffron-yellow disk with a blue tinge to dark brick-red. The moon was known almost disappear out of sight throughout all together, as happened during the lunar eclipse in December 1992, shortly after the eruption of Mount Pinatubo in the Philippines. The meaning used to describe the color and intensity of the moon as it appears in general is known as Dungeon Scale from 4 (bright) to 0 (dark).

The crimson aggregate displayed with an 80mm refractor from Shenandoah NPS on Skyline Drive. Copyright and image: Greg Redfern.

This value depends on two factors. One is how the center of the moon passes through the shadow. During a brief (just under five minutes) eclipse on the night of April 4thth2015, for example, the moon appeared extremely bright on one limb, provoking a lively debate on the estimated and actual size of the Earth’s shadow at a distance to the Moon.

The second factor is the amount of dust and aerosols that are currently in the Earth’s atmosphere. The red color that you see all the time is due to the sunlight of thousands of sunrises and sunsets that is filtered in the cone of the Earth’s shadow from all over the edge. planets. Last year’s eruptions on Tonga, forest fires and dust storms around the world could add to this atmospheric load of the environment, resulting in a rather dark ruddy total lunar eclipse.

Tales of Soros

All eclipses are part of a Saros series, or many eclipses will be almost similar circumstances with an interval of just over 18 years. This works because 223 lunar months are almost equal to 18 years, 11 days and 8 hours (actually only 17 minutes), with each successive eclipse in the same series of saros shifting by about 120 degrees to the west. The Babylonians knew about the Saros cycle and used it to predict eclipses. The Greeks also knew about the Soros eclipse cycle and built this knowledge into the famous anti-guitar mechanism used to predict future eclipses.

Soros develop over time, starting with shallow penumbra, then turning into central total eclipses before retreating. The eclipse this weekend is a member of 34 of the 72 eclipses Lunar Saros 131 series. This series started on May 10th 1427, and will take place its last total lunar eclipse on September 3rdetc. 2022, before the end (note in the calendar) on July 7th 2707 AD.

There are also some interesting projects that can be implemented during a lunar eclipse. One of them is a long-standing effort a time when specific lunar craters enter the shadow, trying to clarify the set diameter of the Earth’s shadow.

Another is trying to measure your longitude during an eclipse. This method used by sailors such as Captain James Cook and (possibly) Columbus. This works because the eclipse gives you a good one-time “hack”, allowing the observer to measure the position of the eclipse moon in the sky compared to the known forecast from a table made for a ground-based observatory.

The totality
Totality through the trees. Copyright and image: Greg Redfern.

You should also watch and view images and videos of meteors that fall into the lunar moon. Just such an event during the c Eclipse in January 2019 and sent many of us to climb to see if we also caught a flash on the lunar limbus. This weekend there is a chance that Fr. Meteor explosion of Hercules provided by the asteroid (comet native?) 2006 GY2 may be active, so it would be a good idea to monitor for any false meteor activity.

Transits and acculturations

Also, be sure to keep an eye out for things that pass before (and behind) the lunar moon. Astrophotographer Chris Beck notes that although we do not have a favorable ISS transit for the US during the eclipse, we do have a transit of the new Chinese space station Tiangun, which crosses the United States around the beginning of the aggregate:

The moon hides a star + 6th magnitude … during an eclipse on Sunday. Credit: Stellarium.

In addition, the Moon will cover the double star +6.3 stars SAO 159317 in the constellation Libra Libra for North America throughout the period. It will be good practice to observe a rare event later this year during the next total lunar eclipse on November 8, when the Moon closes the planet Uranus almost completely.

Occult trail for star + 6th magnitude SAO 159317. Credit: Occult 4.2.

Finally, another unique observation to try to see during a total lunar eclipse is to catch the elusive selenelion, or see both a total lunar eclipse and the rising sun above the horizon. This works because the Earth’s shadow is larger than the Moon, and the Earth’s atmosphere refracts light from both. To accomplish this unique astro-athletics feat, you will need high territory and a completely clear horizon. The best regions to try this during the eclipse on Sunday / Monday morning are between the U2-U3 contact zones (see the eclipse map of the world earlier in this article). These areas cover western Canada at sunset and Iceland, the UK, France and central Africa at dawn.

We are also keeping a close eye on the weather prospects this weekend that are leading to the eclipse. Keep in mind that you don’t need a crystal clear sky to enjoy a lunar eclipse … just a good view of the moon.

Cloud cover
Projected cloudiness percentage for CONUS on Sunday night: credit: NOAA.

Blurred, or do you just live in the wrong hemisphere? Good people from the virtual telescope project were able to reach you live webcast total lunar eclipse, organized by astronomer Gianluca Massi, starting May 15th at 2:15 UT / 22:15 EDT.

Watch the eclipse on Sunday live! Credit: Gianluca Massi.

Don’t miss the first total lunar eclipse in 2022!

Leading image: a mosaic of a total lunar eclipse in November 2021. Copyright and image: Christopher Beck.