New Delhi: In a fascinating new finding, scientists have come across evidence suggesting that liquid water existed on Mars even around 742 million years ago. This was highlighted in a study published by scientists from the US and the UK who analysed the ‘Lafayette meteorite’—one of the only Martian rocks that left the planet 11 million years ago and struck Earth. The study was published in the peer-reviewed journal Geochemical Perspectives Letters on 6 November.
The exact date of when Lafayette meteorite landed on Earth is unknown, but it was discovered in a drawer at Purdue University in 1931.
Now, scientists have analysed this meteorite to understand its chemical composition and create a timeline of all the different rock weathering processes it has undergone. Through this, they realised that this meteorite has seen ‘aqueous alteration’ which means changes as a result of interaction with water. Scientists used mineral dating to identify when exactly the piece of rock came in contact with water, and found that it was around 742 million years ago. This water too, according to the paper, was not from abundant liquid sources but rather melted ice. Read more here.
Also Read: On Mars, clues to an ancient ocean & DNA analysis sheds new light on life & relationships in Pompeii
Drowning mangroves in the Maldives
A new study published in the peer-reviewed journal Scientific Reports on 12 November talks about the phenomenon of drowning mangrove forests in the Maldives. It documents a mangrove ‘dieback’ that affected 25 percent of the mangrove-carrying islands in the Maldives—a startling number, given how mangroves are essential to coastal ecosystems.
The study, by Australian scientists, found that sea level rise, high salinity, coupled with the Indian Ocean Dipole Event, were mainly responsible for these mangrove deaths. Sea level rise is a heavily documented event due to global warming, but what made matters worse in the Maldives was the Indian Ocean Dipole, which is a climatic phenomenon that refers to currents in the Indian Ocean leading to higher-than-normal sea surface temperatures.
Mangroves are seen as important for climate resilience not just in the Maldives but in India too, particularly in the Sunderbans. Read more here.
Drug resistance among Ugandan children
A peer-reviewed study of Ugandan children by American and African scientists found that some children with severe malaria showed resistance to artemisinin, one of the main drugs used to treat malaria. The study was published in Jama Network on 14 November.
Of the 100 children in Uganda suffering from ‘complicated malaria’ and part of the study, scientists found that 11 had a genetic mutation that was resistant to artemisinin. In medical terms, ‘complicated malaria’ is a version of the disease that is severe and requires hospitalisation.
Since the sample size was small, the study called for more research as well as revised guidelines and treatments for malaria if such mutations that resist the current treatment continue to evolve. Read more here.
Skin-tone bias in technique for cancer detection
A new report by researchers from Johns Hopkins University published on 14 November found that darker skin tones are at a disadvantage when it comes to breast cancer detection through photoacoustic imagery.
To arrive at this conclusion, researchers tested the efficiency of the photoacoustic imagery technique, an emerging tool in detecting breast cancer that uses light and sound. They found that the process was unable to capture targets between 0.5 to 3 mm in size in bodies with darker skin tones. Researchers also found that higher melanin content coincided with lower detectability of smaller-sized targets.
However, the scientists were able to zero in on one specific wavelength of light, 1064 nanometers, and an advanced imaging technique, which together helped overcome this skin-tone bias. Read more here.