Tag Archives: magnetosphere

Oxygen and carbon ions detected in Venus’s magnetosphere by BepiColombo

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In August 2021, ESA/JAXA BepiColombo spacecraft bound for Mercury Performed a second flyby of Venus, providing short-term observations of its guided magnetosphere. The spacecraft detected cold oxygen and carbon ions at a distance of about six planet radii, in an area of ​​the magnetosphere that has never been explored before.

Schematic illustration of planetary material escaping through the sides of Venus's magnetic sheath. The red line and arrow indicate the observation region and direction of BepiColombo as the ions escape (C+,oh+,H+) was observed. Image credit: Thibaut Roger / Europlanet 2024 RI / Hadid other.

Venus was similar to Earth in many ways during its formation, including the presence of large amounts of liquid water.

However, Venus eventually underwent a divergent evolution, leading to major differences between the two planets.

Unlike Earth, Venus is currently a very dry planet with no inherent magnetic field.

The continuous influence of the solar wind on the atmospheres of both planets results in significant atmospheric losses.

Venus' atmosphere is primarily composed of carbon dioxide and small amounts of nitrogen and other trace species, and is affected by interactions with the solar wind, leading to significant ion fluxes.

“This is the first time that positively charged carbon ions have been observed to be ejected from Venus's atmosphere,” said Dr. Lina Hadid, a researcher at the Plasma Physics Institute and CNRS.

“These are heavy ions that typically move slowly, so we're still trying to understand the mechanism.”

“An electrostatic 'wind' may be moving them away from Earth, or they may be accelerated by centrifugal action.”

“Unlike Earth, Venus does not generate an intrinsic magnetic field at its core.”

“Nevertheless, interactions between charged particles emitted by the sun (solar wind) and charged particles in Venus' upper atmosphere create a weak, comet-shaped 'induced magnetosphere' around the planet. ”

“Around the magnetosphere there is a region called the 'magnetic sheath' where the solar wind is slowed down and heated.”

On August 10, 2021, BepiColombo passed Venus to slow down and adjust its course towards its final destination, Mercury.

The probe soared up the long tail of the planet's magnetic sheath, emerging from the nose of the magnetic region closest to the sun.

Over a 90-minute observation period, BepiColombo's mass spectrometer (MSA) and mercury ion analyzer (MIA) will measure the number and mass of charged particles encountered, and detect chemical and Captured information about physical processes. magneto sheath.

“Characterizing the loss of heavy ions on Venus and understanding the escape mechanisms will help us understand how Venus's atmosphere evolved,” said Dr. Dominique Delcourt, principal investigator at MSA and researcher at the Plasma Physics Institute. “This is critical to understanding how water is lost.” .

“This result shows a unique result from measurements made during a flyby of a planet, in which the spacecraft may pass through areas that are generally inaccessible to orbiting spacecraft. '' said Dr. Nicolas Andre, a researcher at the Astrophysical and Planetary Institute.

of study It was published in the magazine natural astronomy.

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LZ Hadid other. BepiColombo's observations of cold oxygen and carbon ions on the side of Venus' induced magnetosphere. Nat Astron, published online on April 12, 2024. doi: 10.1038/s41550-024-02247-2

Source: www.sci.news

Decoding Earth’s magnetosphere: A simplified understanding

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Earth’s magnetosphere, essential for protecting us from solar radiation, is in sharp contrast to Mars, which has lost its protective field. Studying this shield, especially through NASA missions such as the Magnetospheric Multiscale Mission, is important for understanding space weather and its effects on Earth.

What is Earth’s magnetosphere?

Enveloping our planet and protecting us from the wrath of the sun is a giant magnetic bubble called the magnetosphere. It deflects most of the solar material that rushes toward us from our star at more than 1 million miles per hour. Without the magnetosphere, the relentless activity of these solar particles could strip Earth of the protective layer that protects us from the sun’s ultraviolet rays. It is clear that this magnetic bubble was the key to the development of Earth into a habitable planet.

The magnetosphere envelops our planet and protects us from the brunt of the sun, and is key to Earth’s development into a habitable planet. credit: NASA

Earth vs. Mars: The role of the magnetosphere

compare with earth Mars – A planet that lost its magnetosphere about 4.2 billion years ago. It is thought that solar winds stripped away most of Mars’ atmosphere, probably after the Red Planet’s magnetic field disappeared. As a result, Mars is the desolate, barren world we see today through the “eyes” of NASA’s orbiters and probes. In contrast, Earth’s magnetosphere appears to continue to protect the atmosphere.

“If we didn’t have the magnetic field, we might be left with a completely different atmosphere, devoid of life as we know it,” said Eftihir Zesta of NASA’s Goddard Space Flight Center’s Geospace Physics Laboratory. states.

The magnetosphere is the result of the Earth’s internal magnetic field, generated by the rotation and convection of electrically conductive material within its central core. This magnetic field spreads out into space and acts as a shield against the solar wind, forming the magnetosphere.

Understanding and researching the magnetosphere

Understanding the magnetosphere is a key element in helping scientists predict space weather that could one day impact technology on Earth. Extreme space weather events can disrupt communication networks. GPS Navigation and power grids.

The magnetosphere is a permeable shield. The solar wind periodically connects to the magnetosphere and forces its reconfiguration. This can cause cracks and allow energy to flow into our safe haven. These cracks open and close many times a day, sometimes even an hour. Most of them are small and short-lived. Others are vast and persistent. When the sun’s magnetic field connects with the Earth’s magnetic field, fireworks begin.

“Earth’s magnetosphere absorbs incoming energy from the solar wind and releases it in bursts in the form of magnetic storms and substorms,” ​​Zesta said.

Illustration of four MMS spacecraft in orbit in the Earth’s magnetic field. Credit: NASA

Magnetic Reconnection and MMS Mission

How does this happen? Magnetic field lines converge and rearrange, resulting in magnetic energy and charged particles flying around at breakneck speeds. Scientists have been trying to understand why this crossing of magnetic field lines, called magnetic reconnection, causes such violent explosions and opens cracks in the magnetosphere.

NASA’s Magnetospheric Multiscale Mission (MMS) launched in March 2015 to make the first observations of the electronic physics of magnetic reconnection. Four of her MMS spacecraft, packed with high-energy particle detectors and magnetic sensors, flew close to the region on the surface of Earth’s magnetosphere where magnetic reconnection occurs. Since then, MMS has conducted similar searches in the magnetotail.

MMS complements the missions of NASA and partner agencies such as THEMIS, Cluster, and Geotail, and will provide important new details for ongoing studies of Earth’s magnetosphere. The data obtained from these surveys not only helps us understand the fundamental physics of the universe, but also helps improve space weather forecasting.

Source: scitechdaily.com