On Tuesday, February 2, Starship serial number 9 (SN9) completed SpaceX’s second high-altitude flight test of a Starship prototype from our site in Cameron County, Texas. SpaceX – Starship

www.spacex.com/vehicles/starship/

On Tuesday, February 2, Starship serial number 9 (SN9) completed SpaceX’s second high-altitude flight test of a Starship prototype from our site in Cameron County, Texas.
Similar to the high-altitude flight test of Starship serial number 8 (SN8), SN9 was powered through ascent by three Raptor engines, each shutting down in sequence prior to the vehicle reaching apogee – approximately 10 kilometers in altitude. SN9 successfully performed a propellant transition to the internal header tanks, which hold landing propellant, before reorienting itself for reentry and a controlled aerodynamic descent.
The Starship prototype descended under active aerodynamic control, accomplished by independent movement of two forward and two aft flaps on the vehicle. All four flaps are actuated by an onboard flight computer to control Starship’s attitude during flight and enable precise landing at the intended location. During the landing flip maneuver, one of the Raptor engines did not relight and caused SN9 to land at high speed and experience a RUD.

ベテルギウスはまだ爆発しない -減光の原因を探り恒星の質量、サイズ、距離を改訂- | Kavli IPMU-カブリ数物連携宇宙研究機構

www.ipmu.jp/ja/20210204-Betelgeuse
2020年初めに前例のない大幅な減光を見せたオリオン座の赤色超巨星ベテルギウスについて、その進化の段階と減光の原因を探るため、明るさの変化を分析しました。その結果、星の脈動に加えて、星から放出された大量の塵が関係していることを示唆し、今回の大幅な減光が超新星爆発の兆候ではないことを示しました。