On Wednesday night’s full Moon was a super blood moon, caused by an eclipse reaching totality and sunlight bent through Earth’s atmosphere to reach it, turning reddish as a result.
Supermoons are rare occurrences which take place when three distinct lunar events come together simultaneously: full Moon, lunar eclipse and blue Moon. It only happens every few years.
How rare is a super blood moon?
Star-gazers around the globe were treated to an incredible astronomical event this week that transformed the Moon into a striking coppery hue. This event coincided with both a super moon (when the full Moon appears close to Earth due to its oval orbit) and lunar eclipse – events which turn the Moon an orangey shade as it passes through Earth’s shadow and turn its surface red when passing through our shadow – producing an eye-catching spectacle that many tweeting about it have shared as magnificent images.
But why is this lunar eclipse and super moon so unique? It marks the last in a lunar tetrad series that started six months earlier; each eclipse in this tetrad has been a blood moon, where sunlight being blocked by Earth’s atmosphere makes the lunar eclipse look reddish-brown in hue. The last eclipse took place on September 28, 2018.
Astrologers first coined the term “super moon,” which refers to when the Moon reaches its closest point during fullness every month – often when full. This occurs roughly every three or four months and occurs only when Earth and Moon are closest together – when this happens it appears 14% larger than when at its furthest point, known as apogee.
An eclipse magnifies and expands the Moon beyond what it normally would appear, and can seem up to 30 percent closer than usual, earning itself the name “Supermoon”.
A super Moon and blood moon may not be as rare as some might believe, but it remains an incredible natural phenomenon worth witnessing. The next super Moon/total lunar eclipse won’t occur again until 2033 so don’t miss this once-in-a-lifetime opportunity!
For those unable to experience it live, several reputable websites have developed animations and videos so you can experience this spectacle virtually.
How often is a blue moon?
Blue moons occur approximately four times every century and often go misinterpreted due to an 1846 Sky & Telescope misinterpretation; for instance, some believe that when two full moons occur within one calendar year, both full moons should be called blue moons with only the first being known as such; making this misleading description particularly problematic for months such as February which only have 28-29 days and cannot host such an occurrence.
A true blue moon occurs when two full Moons occur within one calendar month which also contains a lunar eclipse. This can happen because when the Moon reaches perigee it appears larger; when its orbit reaches Earth’s shadow it can then become eclipsed completely and turn red from being totally covered up by Earth’s shadow causing its color to change to coppery red.
Lunar eclipses are not rare events, but the combination of a blue moon with a total lunar eclipse is extremely uncommon – this event, known as a super blood moon, first occurred since 1866 on 31st January 2018 (when February’s second full Moon also coincided with a lunar eclipse).
There are two different kinds of blue moons: seasonal and calendrical. A seasonal blue moon refers to any time that an extra full Moon is seen during an astronomical season that typically only contains three, occurring around three times every century in most time zones – it will next be visible between 2019-2023.
Calendrical blue moons occur only every 19 years, most often occurring between March and April; their last appearance was in 2015 while the next one won’t happen again until 2024.
How often is a total lunar eclipse?
On Tuesday’s total lunar eclipse will provide an unforgettable sight, one which many astronomy enthusiasts have eagerly been anticipating for some time now. Commonly referred to as a “blood moon”, these rare events occur when the Moon passes through Earth’s shadow, giving it its distinctive reddish tint as sunlight refracted by our atmosphere is refracted back out into space and refracted onto it once again. Visible across most of America from moonset onward, full lunar eclipses only happen approximately every two and half years – make sure that this event won’t pass you by!
To create a blood moon, the Moon must pass through the darkest part of Earth’s shadow and make its closest approach. Additionally, its perigee must also be near, meaning its largest point on its orbit will need to occur near that time too. As a result of these requirements, supermoon lunar eclipses only usually happen when full Moon passes close to our planet, rarely simultaneously.
Next year will bring another chance for people to witness both a super moon and total lunar eclipse in one calendar year, beginning April 20 and lasting through May 5. Eclipse season will kick off April 20 and run through May 5, with its initial pair being a penumbral lunar eclipse followed by total solar eclipse – this being your only chance until 2028 for such an occurrence!
There are various reasons for why lunar eclipses don’t happen every month on a full moon, other than simply weather. Due to Earth’s tilted orbit and moon’s tilt relative to it, lunar eclipses only pass through our planet’s shadow (the umbral shadow) at certain times each year – this means only three eclipses can be witnessed from anywhere on Earth each year.
The next total lunar eclipse and therefore opportunity for both blue moons and total blood moons will take place on March 20, 2025; however, its occurrence won’t be particularly likely as all necessary conditions must come together perfectly in order for such an event to take place.
How often is a supermoon?
Supermoons occur when the Moon’s full phase coincides with its closest approach to Earth in its elliptical orbit. They can appear 14% larger and 30% brighter than usual. Supermoons tend to occur multiple times each year; though not necessarily consecutive months.
Richard Nolle first coined the term’supermoon’ in 1979. His definition included any new or full Moon that is within 90% of its closest distance from Earth; however, different astronomers can have different interpretations of what constitutes a supermoon; this may lead to one source classifying one Moon as super while not another source.
Astronomer Fred Espenak developed the calendar method used by EarthSky to calculate supermoon dates. A former NASA astrophysicist who has spent much of his career predicting eclipses, Espenak’s method takes into account variations in lunar orbital geometry that occurs with each lunar cycle.
Supermoons may not be common, but they tend to gain extra attention due to their enhanced visual impact. Though not much larger or brighter than other full Moons, supermoons appear closer to the horizon than usual due to more sunlight reflecting off of its surface at perigee causing it to appear brighter and larger than usual.
On very rare occasions, supermoons appear together with blue Moons or blood Moons to produce an incredible lunar display. Such was the case on January 21, 2019, when both events happened simultaneously to create an unforgettable lunar show!
Though no evidence supports that supermoons cause dramatic natural events like earthquakes or volcanic eruptions, they may have an insignificant influence on ocean tides; though any effect will only be noticeable to someone looking at it closely.