Vikram Lander does a hop, goes to sleep; goodnight till Sept. 22

Subject: Science and Technology

Section: Space technology

Successful Hop Experiment and Significance

The Chandrayaan-3 mission’s lander, Vikram, recently accomplished a significant feat by executing a successful hop experiment.
On command, Vikram fired its engines and ascended approximately 40 cm before landing safely about 30–40 cm away.
This achievement holds substantial importance for future moon missions, including sample return and human missions.

Vikram and Pragyan’s Soft Landing and Lunar Activities

The lander module, carrying the rover Pragyan, made a soft landing on August 23.
Pragyan was deployed on the lunar surface shortly after.
In-situ measurements conducted by one of Vikram’s payloads confirmed the presence of plasma near the moon’s surface.
Additionally, two payloads detected and verified the presence of sulfur in the moon’s south-polar region.
Pragyan traversed over 100 meters on the moon’s surface.

Vikram and Pragyan in Sleep Mode and Hope for Awakening

ISRO announced that Vikram had been placed in sleep mode, following Pragyan’s earlier transition.
ISRO plans to awaken both Vikram and Pragyan around September 22, 2023, with the expectation of successful reactivation.
Vikram and Pragyan have a mission life of one lunar day (approximately 14 Earth days) due to concerns about electronics’ extreme cold tolerance during lunar nights.
The lunar night can reach temperatures below minus 200°C.

The lander and rover will be in power-saving mode until the lunar night ends, similar to putting a phone in power-saving mode until a charging source becomes available.

Study spots ‘bottleneck’ in human evolution

Introduction:

The human population nearly faced extinction due to a bottleneck event.
A novel genomic analysis technique (FitCoal)sheds light on this critical period in human history.

The Bottleneck Crisis:

Around 930,000 years ago, the ancestors of modern humans experienced a severe population crash.
Drastic climate change triggered this bottleneck, leading to a population of fewer than 1,280 breeding individuals.
Approximately 98.7% of human ancestors were lost at the start of this bottleneck, posing a threat of extinction.
This population constraint persisted for over 100,000 years before recovery.
The bottleneck possibly contributed to the divergence of early humans into two evolutionary lineages, including Neanderthals and modern humans.

Fit Coal (Fast Infinitesimal Time Coalescent):

Researchers in China developed FitCoal, a cutting-edge method for reconstructing human evolution.
FitCoal divides history into fine time slices, enabling a detailed model of evolution.
The study analyzed genomes of 3,154 individuals from 50 global populations.
The pre-bottleneck population consisted of approximately 98,000 breeding individuals.
Researchers speculate that the fusion of chromosomes (forming Chromosome 2 in modern humans) may have occurred after the bottleneck, influencing modern human genetics.

Bottleneck Event in Evolution:

Population Contraction: Bottleneck events involve a sharp reduction in a population’s size.
Genetic Diversity Loss: These events lead to a significant decrease in genetic diversity within the population.
Genetic Drift Impact: Genetic drift, or random allele frequency changes, becomes influential during bottlenecks.
Founder Effect: Sometimes, a small group becomes isolated, leading to a founder effect and distinct genetic characteristics.
Vulnerability Increase: Reduced genetic diversity can make populations more vulnerable to environmental changes, diseases, or threats.
Causes: Bottlenecks can result from natural disasters, habitat changes, overhunting, or disease outbreaks.
Long-term Impact: Bottleneck consequences shape a species’ future evolution and adaptation.