Annecy Sports Orientation

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An eerie spiral lit up the European skies. Here’s why such light shows are becoming more common 
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The shapes can seem to appear out of nowhere: an undulating S-like spiral streaking across the European skies or a glowing orb trailing above the North American coast.

Such strange light shows have been a known feature of rocket launches for years. But as humanity rapidly increases the number of objects propelled into space — more people are inadvertently witnessing the phenomena.

“We’re not used to seeing things that are happening in space in these very low (atmospheric) densities,” said Jonathan McDowell, an astrophysicist and astronomer at the Harvard-Smithsonian Center for Astrophysics, referring to the thin atmosphere that exists at high altitudes and in Earth’s orbit.

When a SpaceX Falcon 9 rocket took off from Florida last week — flying northeastward as it headed for Earth’s orbit to drop off a spy satellite for the US military — it put on a show for millions over the United Kingdom and the European continent.

Shortly after launch, social media users began to report “strange shapes” dancing in the sky.

The scene was “likely to be caused by the SpaceX Falcon 9 rocket,” according to a post on X that the Met Office, Britain’s national weather service, shared after the launch.

The viral images were reminiscent of the “jellyfish” phenomenon that has accompanied some SpaceX launches from Florida and California. Visible from the North American coasts, the “jellyfish” is marked by a massive teardrop-shaped streak of light that grows and stretches as the rocket flies.

Despite their similarities, however, experts said the phenomena of the jellyfish and spiral are distinct.
A ghostly spiral
The eerie bat signal-like spiral following SpaceX’s March 24 military satellite launch formed after the rocket had already made its delivery. The vehicle was preparing to plunge out of orbit and back into Earth’s atmosphere, twirling toward a safe splashdown in the ocean — and leaving fuel in its wake.

Such maneuvers made to dispose of rocket bodies are common after launches.

The Falcon 9 is designed to break into two parts — or “stages.”

The first stage is the bottommost portion of the rocket with nine engines that fire up at liftoff, powering the 230-foot (70-meter) vehicle off the ground. The first-stage booster is also the same part that SpaceX routinely guides to landing after launch and reuses to save money.

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