By Singh Rahul Sunilkumar,
Published by the Hindustan Times, 25 September 2023
Rocket launch may have disrupted Earth’s upper atmosphere, puncturing the ionosphere and causing a faint red glow.
A rocket carrying a United States Space Force satellite blasted off on Thursday night (Friday morning in India) and may have caused a disruption in Earth’s upper atmosphere, experts suggest.
This surprise rocket launch, as it wasn’t publicly announced or live-streamed, drew attention when it produced a massive exhaust plume visible from over 1,500 km away. However, after the plume dispersed, a faint red glow lingered in the sky, indicating that the rocket might have punctured the ionosphere, Spaceweather.com reported.
Stephen Hummel, who observed the launch from the McDonald Observatory in Texas, described it as follows: “A bright exhaust cone expanded to cover a large area of the sky during astronomical darkness. After the cone faded, there was a slight red afterglow,” possibly caused by the rocket creating a hole in the ionosphere, the website added.
The satellite, named “Victus Nox,” is part of a US Space Force experiment called “Victus Nox,” testing the ability of the Firefly Alpha rocket to launch a military satellite with only 24 hours’ notice. The launch took place from Vandenberg Space Force Base in California within 27 hours of clearance.
Earlier in July, another low-Earth orbit launch, a SpaceX Falcon 9 rocket left another exhaust plume. The incidents are becoming frequent more so due to the increase of low earth orbit launches.
What is the ionosphere?
The ionosphere is a layer of charged particles that extends from about 80 to 650 kilometres above the surface of Earth. Alongside the neutral upper atmosphere, the ionosphere delineates the boundary between Earth’s lower atmosphere — where we reside — and the vacuum of space, as defined by the National Aeronautics and Space Administration (NASA).
How do rockets create holes in the ionosphere?
According to Spaceweather.com, when rockets ignite their engines approximately 200 to 300 kilometres above Earth’s surface, they release water (H2O) and carbon dioxide (CO2) into the ionosphere. This process reduces local ionization by up to 70%. A complex sequence of charge exchange reactions between oxygen ions (O+) and molecules from the rocket exhaust generates photons at a wavelength of 6300 Ångströms – the same colour as red auroras.
How dangerous are ionosphere disruptions?
The US space agency further explains that this space boundary coincides with the orbits of many Earth-orbiting satellites, including the International Space Station. Consequently, these satellites can be influenced by the ever-changing conditions in the ionosphere, such as sudden increases in charged particles that amplify drag on satellites and shorten their orbital lifespans.
Both radio and GPS signals traverse through this atmospheric layer or rely on it for signal reflection to reach their destinations. In both scenarios, fluctuations in the ionosphere’s density and composition can disrupt these signals.
The disturbances caused by rocket launches may pose challenges, but they are temporary; re-ionization occurs as soon as the sun rises.
See: Original Article