Current Affairs

Issue

A strong geomagnetic storm recently hit the earth, according to space-monitoring agencies. It is expected to cause impact on earth.

Details

• Disturbance is earth’s magnetosphere is called geomagnetic storm. The area is controlled by magnetic field and protects earth’s inhabitants.

• The solar mass ejections strike earth’s magnetosphere and interact strongly with earth’s own magnetic field.

• The changes in magnetic field results in solar particles travelling down the magnetic field lines, and hit the atmosphere near poles.

Effects

• Solar winds have great effect on earth’s magnetosphere. Solar wind variations can cause geomagnetic storms on earth.

• Decline in earth’s magnetic field strength can be observed. This lasts for about 6-12 hours and recovers gradually.

Sunspots

Sunspots are cool areas on sun’s surface. They are formed when strong magnetic field cool the surface. They appear dark on bright surface.

Coronal mass ejections

Expulsion of plasma and magnetic field from sun’s corona is called as coronal mass ejections. Plasma is a highly ionised gas on the sun.

Dangers associated with geomagnetic storm

• Geomagnetic storm has effects on long-range radio communication and global positioning system devices.

• Satellites, electronics, astronauts and high-altitude pilots can be affected due to high levels of radiation.

• Power supply can be affected and outages caused as a result of voltage surges due to altered magnetic activity.

• The northern light, Aurora borealis, are also intensified due to geomagnetic storms. They will be visible brighter in the skies of higher latitudes.

Issue

Satellites of Starlink were impacted due to a geomagnetic storm shortly after their launch on February 3.

Background

There are incidents of failure of satellites due to solar storms but losing almost all in a single batch has been unheard of.

Details

• The storm caused 40 of the 49 satellites to fall from orbit before they could be commissioned. These satellites were launched by Falcon 9 rocket to approximately 210 km above Earth.

• The failed satellites did not cause space junk as they were designed to burn out immediately on entering the earth’s atmosphere.

Solar storms

• Magnetic plasma ejected from the solar surface at great speed is termed as solar flare/ storm. They are known to release magnetic energy associated with sunspots.

• Solar storms occurred on February 1&2 but its effects were seen on February 3rd. They can last for minutes or hours.

Effects on Earth

• Solar Energetic Particles (SEPs), high-speed solar winds, and coronal mass ejections (CMEs) can come near to Earth’s atmosphere and impact weather events.

• They can impact space-dependent services like global positioning systems (GPS), radio, and satellite communications.

• Geomagnetic storms can affect high-frequency radio communications and GPS navigation systems. Power grids, aircraft flights, and space exploration programmes are vulnerable.

• Coronal Mass Ejections can create disturbances in the magnetosphere. Astronauts on spacewalks face health risks from possible exposure to solar radiation.

Prediction of solar storms

• Computer models are used by scientists to predict solar storms and solar activities. Current models can predict a storm’s time of arrival and its speed.

• More intense magnetic storms can be triggered due to certain orientations of the magnetic field.

• Prediction of solar storms is absolutely necessary due to global dependence on satellites for almost every activity.

Sun spots

Sunspots are ‘dark’ regions on the Sun that are cooler than the surrounding photosphere and show high magnetic activity.