Chandrayaan-2 found plasma density in the Moon’s ionosphere (GS Paper 3, Science and Tech)
Why in news?
- Recently, the Chandrayaan-2 found that there is a plasma density in the Moon’s ionosphere.
What is the latest finding?
- The spacecraft hovering in lunar orbit discovered that the Moon’s ionosphere has a plasma density in the wake region, which is at least one order of magnitude more than what is present on the day side.
- The spacecraft has been studying the lunar surface ever since it arrived in orbit in 2019.
- The observed plasma density in the Lunar wake region opens new dimensions in understanding the lunar dark side plasma environment.
- In the wake region, neither the solar radiation nor the solar wind interacts directly with the available neutral particles, but still, the plasma is getting generated.
Dual Frequency Radio Science (DFRS):
- The spacecraft used its Dual Frequency Radio Science (DFRS), designed to study the lunar ionosphere. The instrument uses two coherent signals at the S-band (2240 MHz) and X-band (8496 MHz) of radio frequencies, transmitted from the Chandrayaan-2 orbiter and received at the ground station at Byalalu, Bangalore to explore the lunar plasma ambiance using the radio occultation (RO) technique.
- The measurements made using DFRS have shown that the moon’s ionosphere has a plasma density of 104 per cubic centimetre in the wake region, which is at least one order of magnitude more than that present on the day side.
- ISRO said that simultaneous measurements by two coherent radio signals help to mitigate the effect of the Earth’s atmosphere and any uncertainties due to various sources during the experiments.
- A total of 12 such radio occultation experiments were conducted in campaign mode on four different occasions.
Ray-tracing of radio signals in the lunar ionosphere. A1 is the point of impact factor on the given ray path. (Photo: ISRO)
Large electron content:
- The Indian space agency said that large electron content is also seen near lunar polar regions during solar twilight conditions.
- Numerical simulations of the dark side of plasma environment using a 3-dimensional Lunar Ionospheric Model (3D-LIM) developed at SPL that the production of ions by charge exchange reactions may play a pivotal role in producing a significantly large plasma density in the Lunar wake region, which can sustain for a longer period.
- The model suggests that the dominant ions in the wake region are argon and neon, which have a comparatively longer lifetime than the molecular ions of carbon dioxide and water that are dominant in other regions.
Background:
- The Chandrayaan-2 orbiter, which will be used with the Chandrayaan-3 mission, had previously looked at the Sun and found an abundance of magnesium, aluminum, and silicon in the solar corona and observed around 100 microflares, providing new insights about coronal mass heating.
Way Forward:
- These observations are unique in nature as they show post-sunset enhancements in the iEDPs compared to dayside, as reported by earlier missions.
- These results further confirm recent predictions from the theoretical model for the lunar ionosphere.
NRC in Manipur
(GS Paper 2, Governance)
Why in news?
- Recently, the 60-member Manipur Assembly resolved to implement the National Register of Citizens (NRC) and establish a State Population Commission (SPC).
- The approval came after more than two dozen organisations, most of them tribal, demanded an Assam-like NRC to protect the indigenous people from a perceived demographic invasion by “non-local residents”.
Why is Manipur pushing for NRC?
- The northeastern States have been paranoid about “outsiders”, “foreigners” or “alien cultures” swamping out their numerically weaker indigenous communities. Manipur, home to three major ethnic groups, is no different.
- These ethnic groups are the non-tribal Meitei people concentrated in the Imphal Valley, the central part of Manipur, and the tribal Naga and Kuki-Zomi groups mostly inhabiting the hills around.
- There has been a history of conflict among these three groups, but the NRC issue has seemingly put the Meiteis and the Nagas on the same page.
Link to Military coup in Myanmar:
- They claim that an NRC is necessary because the political crisis in neighbouring Myanmar, triggered by the military coup in February 2021, has forced hundreds of people into the State from across its 398-km international border.
- A majority of those who fled or are fleeing belong to the Kuki-Chin communities, ethnically related to the Kuki-Zomi people in Manipur as well as the Mizos of Mizoram.
- In July, seven Manipur students’ organisations and 19 tribal and mixed groups submitted a memorandum to Prime Minister Narendra Modi and Home Minister Amit Shah demanding the implementation of NRC and the establishment of an SPC to “check and balance the population growth”.
- The State Assembly bowed to these demands and decided to go for NRC and SPC.
Protective mechanisms:
- In December 2019, Manipur became the fourth northeastern State to be brought under the inner-line permit (ILP) system after Arunachal Pradesh, Mizoram and Nagaland.
- A temporary official travel document to allow inward travel of an Indian citizen into a protected area, the ILP is implemented under the British-era Bengal Eastern Frontier Regulation.
- But less than two years later, an umbrella organisation that spearheaded the ILP movement said the system was flawed and that Manipur needed a stronger and more effective mechanism for protecting indigenous populations.
- The pro-NRC organisations said Manipur did have a robust pass or permit system that regulated the entry and settlement of outsiders. But it was abolished by the then chief commissioner Himmat Singh in November 1950, a tad more than a year after Manipur’s merger with the Union of India. This led to the increase “beyond imagination” in the population of non-indigenous people.
- They also recalled a movement in the 1980s for the detection and deportation of foreigners from Manipur, following which the State government had signed two agreements for using 1951 as the base year for identifying the non-residents and evicting them.
- In June 2022, current government approved 1961 as the base year for identifying the “natives” for the purpose of ILP. Most groups are not happy with this cut-off year and insist on 1951 as the cut-off year for the NRC exercise.
Are Myanmar nationals the only bugbears?
- According to data presented in the Manipur Assembly, the population growth rates in the hill districts of the State were 153.3% between 1971 and 2001 and 250.9% between 2001 and 2011 compared to the corresponding national growth rate of 87.67% and 120% respectively.
- In the case of the valley (Imphal and Jiribam, a small patch adjoining southern Assam’s Barak Valley) districts, the growth rate was 94.8% and 125.4% during these periods. The abnormal population growth rates of the hill districts point to a strong possibility of a huge influx of non-Indians.
- The situation is such that smaller indigenous communities may face extinction, necessitating a study and action. This indicated the government had Myanmar nationals, primarily the Kukis, on its radar.
Migrants:
- Kukis are not the only communities to be viewed as demographic invaders. The pro-NRC groups have identified “Bangladeshis” and Muslims from Myanmar who have “occupied the constituency of Jiribam and scattered in the valley areas”, as well as Nepalis (Gurkhas) who have “risen in tremendous number”. The Kukis have termed the threat perception irrational.
- The Kuki Inpi, the apex body of the community, said an NRC implemented with 1961 or 1951 as the cut-off year will not succeed and would affect some Meiteis and Nagas too.
- The major worry for the Kukis are community members who had to relocate from Senapati, Tamenglong and Ukhrul districts after an alleged ethnic cleansing by Naga extremist groups.
What is the status of the NRC elsewhere in the northeast?
Assam:
- Assam is the only State in the region that undertook an exercise to update the NRC of 1951 with March 24, 1971, as the cut-off date for citizenship of a person.
- This date, incorporated in the Assam Accord of 1985 that ended a six-year anti-foreigners movement, was chosen because a large number of people were believed to have crossed over from erstwhile East Pakistan from March 25, 1971, onwards after Pakistan launched an operation to effectively start the Bangladesh liberation war.
- The complete draft of the Assam NRC was published in August 2019, excluding 19.06 lakh out of 3.3 crore applicants, which the BJP-led government in the State and some indigenous groups have refused to accept. Their petitions for re-verification of the NRC to weed out “Bangladeshis”, allegedly included erroneously or fraudulently, are pending before the Supreme Court, which had monitored the exercise.
Nagaland:
- Nagaland attempted a similar exercise called RIIN (Register of Indigenous Inhabitants of Nagaland) in June 2019 to primarily sift the indigenous Nagas from the non-indigenous Nagas.
- The move, seen as directed particularly against the Nagas of adjoining Manipur, was shelved following opposition from several groups, including the extremist National Socialist Council of Nagalim or NSCN (I-M), the bulk of whose members are ironically from Manipur.
Chellanam’s new tetrapod-based seawall
(GS Paper 1, Geography)
Context:
- Over the past few years, Chellanam, an idyllic coastal village in Kerala’s Ernakulam district, would unfailingly hit the headlines during the monsoons for massive sea incursion and widespread destruction of homes.
- However, this monsoon, despite heavy spells of rain lashing Ernakulam district from May, Chellanam has remained largely unaffected due to the construction of a new tetrapod-based seawall.
Background:
- Earlier, the conventional seawall of Chellanam failed to check sea ingress which resulted in massive ruin and destruction. This triggered one of the longest-running protest campaigns, which is now well past 1,000 days, demanding a permanent solution.
- Coastal erosion, which intensified after Cyclone Ockhi in 2017 further worsened with Cyclone Tauktae last year, leaving many residents in relief camps for extended periods.
- Since then, many of them chose to either seek rented accommodation for shorter durations or relocate forever by selling off their small holdings under the State Fisheries Department’s Punargeham project in the face of periodic onslaught by the sea which rendered their homes uninhabitable.
- Now, due to the tetrapod-based seawall, residents of the coastal village vouch that even those stretches that were most vulnerable to sea erosion have remained by and large safe.
What are the contours of the seawall project?
- The construction of the tetrapod-based seawall forms the foundation of the ₹344 crore coastal conservation project being implemented by the State government in Chellanam.
- The six networks of groynes being erected along the Chellanam Bazar area, which used to face the wrath of the sea in the past, are also part of the project.
- In the first phase, the wall is being constructed in a little over seven-km stretch between Chellanam harbour and Puthanthodu.
- The project was launched on the basis of a study conducted by the Chennai-based National Centre for Coastal Research (NCCR) while the work is being supervised by the Anti-Sea Erosion Project Management unit of the Irrigation department.
- Tetrapods are being set upon a 2.5-metre foundation of granite and at a height of 6.1-metre from sea level as per the norms set by the NCCR. A three-metre-wide walkway is being readied over the tetrapod seawall along a stretch of 6.6-km in the first phase.
How much has the project progressed?
- Although the project was formally inaugurated by Chief Minister in July, work had commenced a few months before that.
- On an average, Kozhikode-based Uralungal Labour Contract Co-operative Society (ULCCS) deploys about 350 tetrapods of different tonnage depending on the depth of the sea along the coast.
What lies ahead?
- Demand is already rife for the launch of the project’s second phase to extend the seawall along the remaining 10-km stretch of the coastal part between Kannamali and Kaithaveli.
- It is understood that the estimate for the next phase is being drawn up right now.
- In addition, a detailed project report (DPR) for a ₹941-crore scheme to develop Chellanam into a model, eco-friendly fishing village has also been submitted to the State government by the Kerala University of Fisheries and Ocean Studies (KUFOS) and Kerala State Coastal Area Development Corporation (KSCADC).
How has the project been perceived?
- There are still voices of dissent. The Chellanam Janakeeya Vedi, which has been at the forefront of the protest demanding a permanent solution to sea erosion, dismisses the tetrapod-seawall as a temporary solution at best.
- The group is peeved about the ‘publicity’ garnered by the success of the project, which it sees as a “political ploy by the government to hide its failures”. Beach nourishment reducing the depth of the sea along the shore alone offers a permanent solution, it contends.
- Meanwhile, environmentalists have warned that large scale extraction of stones to manufacture tetrapods could aggravate the natural disasters that the State has been witnessing lately.
