Science News Roundup: In an ancient shark showdown, 'Jaws' may have doomed 'The Meg'; U.S. FAA delays SpaceX final environmental decision to June 13 and more

The agency said in April SpaceX had made multiple changes to its application that required additional FAA analysis.SpaceX founder Elon Musk said in February he was "highly confident" his new SpaceX Starship, designed for voyages to the moon and Mars, would reach Earth orbit for the first time this year. Exclusive-Rocket propulsion startup to offer new, bigger rocket engine in 2025-CEO U.S. rocket engine maker Ursa Major is developing a new medium to heavy-lift rocket engine to serve a growing field of potential customers, jumping into territory dominated by a handful of heavyweights, the startup's chief executive told Reuters.

Following is a summary of current science news briefs.

In an ancient shark showdown, 'Jaws' may have doomed 'The Meg'

An examination of the zinc content of teeth from sharks both living and extinct is providing clues about the demise of the largest-known shark, indicating the mighty megalodon may have been out-competed by the great white shark in ancient seas.

Researchers assessed the ratio of two forms of the mineral zinc in an enamel-like material called enameloid that comprises the outer part of shark teeth. This ratio enabled them to infer the diets of the sharks and gauge their position on the marine food chain.

U.S. FAA delays SpaceX final environmental decision to June 13

The Federal Aviation Administration (FAA) on Tuesday again delayed completing a final environmental assessment of the proposed SpaceX Starship spacecraft and Super Heavy rocket program in Boca Chica, Texas until June 13. In late April, the FAA extended the target date to May 31 for a decision, saying it was "working toward issuing the final Programmatic Environmental Assessment" after several delays. The agency said in April SpaceX had made multiple changes to its application that required additional FAA analysis. SpaceX founder Elon Musk said in February he was "highly confident" his new SpaceX Starship, designed for voyages to the moon and Mars, would reach Earth orbit for the first time this year.

Exclusive-Rocket propulsion startup to offer new, bigger rocket engine in 2025-CEO

U.S. rocket engine maker Ursa Major is developing a new medium to heavy-lift rocket engine to serve a growing field of potential customers, jumping into territory dominated by a handful of heavyweights, the startup's chief executive told Reuters. Ursa Major Technologies Inc, founded in 2015 by a veteran of Elon Musk's SpaceX, expects to launch the Arroway engine in 2025 as a rival offering to those sold now by Aerojet Rocketdyne Holdings and Jeff Bezos' space company Blue Origin.

(With inputs from agencies.)