In this week's space news, the long lived Arecibo radio telescope fell as SpaceX performed their long-awaited test flight for Starship SN8.
The Arecibo Telescope was built in 1963 in Puerto Rico. The telescope has been short in funding for many years, and in recent months it has been physically crumbling as well. A few weeks ago one of the cables snapped even though it was under less stress than its calculated tolerance. Since then the telescope has been demolished. You can watch the demolition here.
Arecibo Observatory was unique not because of its size but because of its ability to send signals. Famously, the Arecibo sent a message in November 1974 to a starcluster about 25,000 light years away. The message, a beacon of light, for potential alien life, “We are here.” If civilization collapses that message will still be ringing though space, waiting for somebody to hear it. Click here to go to the Wiki article.
In long-awaited news, SpaceX tested their Starship SN8! The entire space community watched as Starship fired its 3 raptor engines, reaching roughly 12.5 km as it pitched completely sideways like a skydiver, then fell. When Starship approached the ground, two engines lit up, pointing upright again. Then, one engine shut off completely, only after a few seconds after ignition. The other engine showed bright green streaks, then went completely green...just as Starship performed a rapid unscheduled disassembly (RUD). Elon Musk has tweeted that the failure was most likely caused by “low header tank pressure”.
Fuel header tank pressure was low during landing burn, causing touchdown velocity to be high & RUD, but we got all the data we needed! Congrats SpaceX team hell yeah!!— Elon Musk (@elonmusk) December 9, 2020
Header tanks are smaller tanks that push the fuel towards the engines so the engines have fuel. In Starship SN8, the header tanks did not push enough of the propellant to the engines. This caused one engine to fail.
The second engine had green streaks, likely caused by the engine itself breaking apart in tiny pieces. The copper alloy of the raptor engine mixed with the exhaust as it broke apart, producing a bright green flame.
Despite the crash landing, this is a huge success for Space X. Space X will continue to test, and engineer incredible advances in rocket science. This is not a setback at all. The entire way that SpaceX improves their technology is by engineering, testing, failing, learning and repeating.
Scott Manley did a great analysis of the flight. You can watch his video here.
Watch the official Space X’s live stream of the event here.
(Liftoff occurs at 1:48:12 and landing occurs at 1:54:40.)