A team of Indian scientists from the Indian Institute of Geomagnetism (IIG) reported the first evidence of the presence of solitary waves around Mars in a first-of-its-kind discovery.
What are Solitary Waves?
- Solitary waves are distinct (bipolar or monopolar) electric field fluctuations with constant amplitude-phase relationships.
- Their shape and size are less affected as they spread.
- Solitary waves are thought to be in charge of plasma energization and transport in the Earth’s magnetosphere.
Uncovering the hidden solitary waves
- The Earth is a massive magnetic entity encased in a magnetosphere created by the movement of molten iron in its core.
- This magnetosphere forms a protective layer around our home planet, shielding us from the Sun’s solar winds.
- However, unlike Earth, Mars lacks a strong intrinsic magnetic field, allowing the high-speed solar wind to interact directly with the Martian atmosphere.
- This interaction suggests that, even with a weak and flimsy magnetosphere, solitary waves on Mars are still a possibility.
Why is this a significant achievement for India?
- Despite several Mars missions, their presence was never detected — until now.
- Indian scientists, on the other hand, have successfully identified and reported the first-ever solitary waves detected on Mars.
- They arrived at this conclusion by analysing approximately 450 solitary wave pulses observed by NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft’s Langmuir Probe and Waves instrument.
Decoding the data
- Their analysis revealed distinct electric field fluctuations lasting between 0.2 and 1.7 milliseconds.
- Such signals were most common between dawn and dusk at altitudes ranging from 1000 to 3500 kilometres above Mars’ surface.
- More research is needed to determine why these waves are dominant at certain times of the day.
The importance of such waves on Mars
- These pulses are most visible at an altitude of 1000-3500 km around Mars in the dawn and afternoon dusk sectors.
- Researchers are investigating their role in particle dynamics in the Martian magnetosphere, as well as whether such waves contribute to the loss of atmospheric ions on Mars.
- The study of these waves is critical because wave-particle interactions directly control particle energization, plasma loss, transport, and so on.
Source: https://pib.gov.in/PressReleasePage.aspx?PRID=1891584