India's landmark mission to the moon- Chandrayaan-2 launched successfully

Mathi, venmathi, thanmathi, thingal, ambuli, nila, chandamama and more – all names of that shining cool one seen in the sky in the night – Chandran ! -the moon. Luna  by the Romans, Selene and Artemis by the Greeks, and many other names in other mythologies. The Moon is revered liked and held high since prehistoric times. It is the second brightest object in the sky after the Sun. As the Moon orbits around the Earth once per month, the angle between the Earth, the Moon and the Sun changes; we see this as the cycle of the Moon's phases.  There have been many misconceptions too – for  centuries, people have thought that a full moon has somehow been associated with insanity, behavioural changes, seizures, fertility, .. .. the word “luancy” comes from the Latin word “luna” meaning “moon.”  It takes about a month for the Moon to orbit Earth (27.3 days to complete a revolution, but 29.5 days to change from New Moon to New Moon).

A great day for the Nation .. .. … India's landmark mission to the moon- Chandrayaan-2 was launched from the Satish Dhawan Space Centre at Sriharikota in Nellore district of Andhra Pradesh at 2.43 pm today. This was the second attempt at launch. The first attempt on 15 July was aborted due to technical glitch.

As the Moon orbits around the Earth once per month, the angle between the Earth, the Moon and the Sun changes; we see this as the cycle of the Moon's phases. The Moon moderates Earth’s wobble on its axis, leading to a relatively stable climate over billions of years. From Earth, we always see the same face of the Moon because the Moon is spinning on its axis at the same speed that it is going around Earth (that is, it is in synchronous rotation with Earth).

The light areas of the Moon are known as the highlands. The dark features, called maria (Latin for seas), are impact basins that were filled with lava between 4.2 and 1.2 billion years ago. These light and dark areas represent rocks of different composition and ages, which provide evidence for how the early crust may have crystallized from a lunar magma ocean. The craters themselves, which have been preserved for billions of years, provide an impact history for the Moon and other bodies in the inner solar system.

The leading theory of the Moon’s origin is that a Mars-sized body collided with Earth approximately 4.5 billion years ago, and the resulting debris from both Earth and the impactor accumulated to form our natural satellite. The newly formed Moon was in a molten state. Within about 100 million years, most of the global “magma ocean” had crystallized, with less-dense rocks floating upward and eventually forming the lunar crust.

The Moon was first visited by the Soviet spacecraft Luna 2 in 1959. It is the only extra-terrestrial body to have been visited by humans. The first landing was on July 20, 1969; the last was in December 1972. In the summer of 1994, the Moon was very extensively mapped by the little spacecraft Clementine and again in 1999 by Lunar Prospector. Most rocks on the surface of the Moon seem to be between 4.6 and 3 billion years old. Prior to the study of the Apollo samples, there was no consensus about the origin of the Moon. Chandrayaan 2 is a lunar mission that will boldly go where no country has ever gone before — the Moon's south polar region. Through this effort, the aim is to improve our understanding of the Moon — discoveries that will benefit India and humanity as a whole. These insights and experiences aim at a paradigm shift in how lunar expeditions are approached for years to come — propelling further voyages into the farthest frontiers.

Chandrayaan-2 is unique because it will explore and perform studies on the South Pole region of lunar terrain which is not explored and sampled by any past mission. This mission will offer new knowledge about the Moon.Minutes after India’s second moon mission was launched, ISRO chief K Sivan  announced that the country’s most powerful rocket, GSLV MK-III, had successfully placed Chandrayaan 2 in the Earth orbit.“I am extremely happy to announce that the GSLV MK-III successfully injected Chandrayaan 2 spacecraft into Earth Orbit. It is the beginning of a historic journey of India towards the moon and to land at a place near the South Pole to carry out scientific experiments,” Sivan said.Crediting the scientists who worked relentlessly over the past week to remove the technical glitch that had stopped the initial launch of Chandrayaan 2 on July 15, Sivan said ISRO had bounced back with flying colours.

“After a major technical snag in the launch vehicle earlier, ISRO has come out with flying colours. Work done in the 24 hours after technical snag was mindboggling. In the following one-and-a-half days, we took corrective measures,” the space agency chief said.Moon provides the best linkage to Earth’s early history. It offers an undisturbed historical record of the inner Solar system environment. Though there are a few mature models, the origin of Moon still needs further explanations. Extensive mapping of lunar surface to study variations in lunar surface composition is essential to trace back the origin and evolution of the Moon. Evidence for water molecules discovered by Chandrayaan-1, requires further studies on the extent of water molecule distribution on the surface, below the surface and in the tenuous lunar exosphere to address the origin of water on Moon.

The lunar South Pole is especially interesting because of the lunar surface area here that remains in shadow is much larger than that at the North Pole. There is a possibility of the presence of water in permanently shadowed areas around it. In addition, South Pole region has craters that are cold traps and contain a fossil record of the early Solar System.Chandrayaan-2 will attempt to soft land the lander -Vikram and rover- Pragyan in a high plain between two craters, Manzinus C and Simpelius N, at a latitude of about 70° south.

The GSLV Mk-III that carries Chandrayaan 2 to its designated orbit is three-stage vehicle capable of launching 4-ton class of satellites to the Geosynchronous Transfer Orbit (GTO).Its components are:S200 solid rocket boosters; L110 liquid stage&C25 upper stage.

Great day for the Nation ~ Hail Chandrayaan-2- hail our Scientists of ISRO.

Elsewhere, as the world marked the 50^th anniversary of the first Moon landing, the US space agency said it has doubled down on its next giant leap with the Artemis programme that would take "the first woman and the next man" to the lunar surface."Artemis" is named after the twin sister of Apollo who is also the Goddess of the Moon and the hunt."Artemis will light our way to Mars. The new Artemis identity draws bold inspiration from the Apollo programme and forges its own path, showing how it will pursue lunar exploration like never before and pave the way to Mars," NASA said in a statement.The astronauts would explore regions of the Moon never visited before, unlock mysteries of the Universe and test the technology that will extend the bounds of humanity farther into the solar system.

"On the lunar surface we will pursue water, ice and other natural resources that will further enable deep space travel. From the Moon, humanity will take the next giant leap to Mars," said the agency.

Interesting !

With regards – S. Sampathkumar

22^nd July 2019.