‘Once in a Blue Moon’ - Super Blue Moon 2023

‘Once in a Blue Moon’ 

For sure have heard this !  Today is Super Blue Moon ! – what ! – rush out of home to see this and enjoy.  Before that enjoy this iconic image of rover Vikram captured by its co-traveller Pragyan today  around 11 am IST from about 15 m, released by ISRO.

 

India on August 23 scripted history as ISRO's ambitious third Moon mission Chandrayaan-3's Lander Module (LM) smoothly touched down on the lunar surface, making it only the fourth country to accomplish the feat and the first to reach the uncharted south pole.  A few hours later, the rover Pragyan  rolled out on the moon's surface, various observations have been made in pursuit of lunar secrets at the South Pole. 

Of the three objectives of Chandrayaan Moon Mission, two is complete while the third is currently underway. Demonstration of a Safe and Soft Landing on the Lunar Surface and demonstration of Rover roving on the moon are accomplished. While the third objective, conducting in-situ scientific experiments is currently underway. 

On 27 August, ISRO released a graph of the temperature variation on the lunar surface and a senior scientist of the space agency also has expressed surprise over the high temperature recorded on the Moon. The space agency shared an update saying that Chandra's Surface Thermophysical Experiment (ChaSTE) payload onboard Chandrayaan-3's Vikram lander measured the temperature profile of the lunar topsoil around the pole to understand the thermal behaviour of the Moon's surface.   On 30 August, the Laser-Induced Breakdown Spectroscope instrument onboard 'Pragyan' rover of Chandrayaan-3 ‘unambiguously confirmed’ the presence of sulphur in the lunar surface near south pole. Other elements like Aluminum (Al), Calcium (Ca), Iron (Fe), Chromium (Cr), Titanium (Ti), Manganese (Mn), Silicon (Si), and Oxygen (O) are also detected. The space agency further added that the search for Hydrogen (H) is underway.  

Meanwhile, scientists have said that the rover is currently in a “race against time" with ISRO working to cover a maximum distance of the uncharted South pole through the six-wheeled vehicle. “We have only 14 days in total for this mission, which is equal to one day on the moon, so four days have been completed.   

 

For sure, lot of new learning about the Moon is happening – when someone says  "Once in a blue moon …" it refers  something rare.  Stargazers are in for another treat  today.  The most significant lunar phenomenon of the year is happening for a second time this month, also known as the super blue moon. Depending on your location in the globe, you can catch sight of the super blue moon either on August 30 or 31. 

A full moon occurs when the side of the Moon facing Earth is fully lit up by the Sun.  Not all full moons look the same!  Sometimes, the Moon may appear to glow red. Other times, the Moon may appear larger than usual in our night sky. The Moon itself is not changing colors or sizes. Its changes in appearance are usually due to its position in relation to the Sun and Earth.  The different types of unusual full moon types include blood moons, supermoons, blue moons, and harvest moons, and others. 

Despite its name, the moon won’t appear blue; rather, the term ‘blue moon’ denotes a second full moon occurring within a month. This month’s second full moon, also referred to as the blue moon is also the first super blue moon of the year, as the moon will be at its closest proximity to Earth, at a distance of 357,344km. To add to the spectacle, Saturn will also be visible as a bright point approximately five degrees above the moon’s upper part. 

Earth’s only natural satellite, the moon, follows an elliptical orbit around our planet. Consequently, when the moon reaches its closest point to Earth, known as perigee, it’s classified as a Super moon. Due to the reduced distance between Earth and the moon, the lunar body appears larger, fuller, and brighter than during regular phases. According to NASA, spotting a blue moon or super moon is relatively common a few times each year, whereas, a super blue moon, where both phenomena coincide, only happens roughly once in a decade. Hence, the second full moon of August 2023,  qualifies as a super blue moon. The subsequent super blue moon is not anticipated until January 2037, underscoring the significance of this upcoming event. 

A seasonal Blue Moon is the traditional definition of a Blue Moon and refers to the third full moon in a season that has four full moons according to NASA.   As the cycle of the phases of the moon lasts approximately one month, we typically experience 12 full moons each year. Many cultures have given distinct names to each month's full moon. 12 months, 12 full moons, 12 names. Simple right?  NO. The moon phases actually take 29.5 days to complete which means it takes just 354 days to complete 12 lunar cycles. So every 2.5 years or so a 13th full moon is observed within a calendar year.  This 13th full moon doesn't conform to the normal naming scheme and is referred to as the Blue Moon.

 

So if you are reading this now, rush out to experience the bliss of a Super Blue Moon.  I saw that from my house window and here is a photo of the moon too.

 
With regards – S. Sampathkumar
@ 21.00 hrs of 30.8.2023