SpaceX rockets descending from orbit are forming momentary voids in the upper atmosphere, giving rise to radiant red spheres termed "SpaceX auroras." The phenomenon arises from the rockets piercing the ionosphere, situated 50 to 400 miles above Earth, resulting in ionospheric holes, provoking vibrant red streaks akin to auroras.
The well-known phenomenon has been acknowledged for some time, prompting a reevaluation of the wider consequences associated with these events. Despite posing no threat to the environment or terrestrial life, scientists voice apprehension over potential, yet undiscovered ramifications.
SpaceX's Pioneering Ventures: Reusable Booster Create a New Type of Aurora
Elon Musk's private spaceflight company, SpaceX, maintains a steady flow of US government contracts for regular rocket launches, while their Starlink satellite internet system, with thousands of satellites in low Earth orbit, adds to their operational portfolio.
Notably, SpaceX utilizes reusable rocket boosters, enabling controlled descents back to the launch pad, marked by small rocket bursts that generate mini-auroras during the maneuvering process.
In specific instances, such as in July, a Falcon 9 rocket transporting Starlink satellites tore open an atmospheric hole above Arizona, causing a peculiar visual phenomenon. Similarly, a US Space Force rocket in September unintentionally created an ionospheric hole above California, resulting in a subtle red glow in the sky.
Recent observations by astronomers at Texas' McDonald Observatory reveal distinctive red lights persisting long after SpaceX's Falcon 9 rockets exit Earth's atmosphere. Unlike the prolonged streaks seen during rocket launches, these smaller, spherical lights are attributed to ionospheric holes formed by the rockets' secondary boosters during their descent.
The first occurrence of these unique "SpaceX auroras" was noted above the observatory in February, and astronomers now observe "2 to 5 of them each month," according to Stephen Hummel, an astronomer and outreach program coordinator at McDonald Observatory.
These red orbs, characterized as "very bright" and visible to the naked eye, endure for about 20 minutes before the sun's potent radiation reionizes the molecules, stripping away their electrons and closing the holes.
READ ALSO: Elon Musk's SpaceX Launch of Falcon 9 Rocket Punctures a Temporary Hole in Earth's Ionosphere
How Do 'SpaceX Auroras' Form?
Rocket launches and de-orbiting boosters induce ionospheric holes by releasing fuel into the ionosphere, causing ionized oxygen atoms to recombine and emit red light, similar to traditional auroras.
Moreover, SpaceX rocket boosters descending to the southern Atlantic Ocean create smaller, circular holes about 90 minutes post-launch, appearing more frequently than those from rocket launches.
While ionospheric holes pose no threat to Earth's surface, their impact on astronomical science is under evaluation, and changes to the ionosphere may disrupt radio communication and GPS signals. Studying these events helps scientists understand ionospheric chemistry and density variations, offering insights into the efficiency of the ionosphere's processes.
SpaceX's rocket boosters also generate "SpaceX spirals," bright spirals in the night sky created by spinning boosters dumping leftover fuel, forming illuminated clouds of tiny ice crystals. With the increasing frequency of SpaceX launches, these phenomena are likely to become more common in the future.
RELATED ARTICLE: Space Force's Lightning-Fast Satellite Launch: Did It Punch a Hole in the Ionosphere?
Check out more news and information on SpaceX in Science Times.