The phrase "astonishing development" is correct and usable in written English.
It can be used to describe a surprising or remarkable change or event in various contexts, such as news articles, reports, or discussions about progress.
Example: "The scientists announced an astonishing development in renewable energy technology that could revolutionize the industry."
Alternatives: "remarkable advancement" or "incredible breakthrough".
This is a truly astonishing development.
What are we to make of this astonishing development?
That's an astonishing development, considering Apple's traditional protectiveness of its software.
We learn much about the (astonishing) development of social security under Weimar, about seething anti-Semitism and diplomatic blunders.
To longtime fans, the notion of the hidebound Cubs as a laboratory for innovation is an astonishing development.
Begin with the astonishing development that the bullpen appears to have remained armed and dangerous despite being without Rivera in the closer's role for the first time in 15 years.
Among the many astonishing developments that have arisen in the wake of Bear Stearns' final meltdown is the level of involvement of the Federal Reserve System.
Still, Mr. Gauck joins Angela Merkel, the German chancellor, in one of the most astonishing developments of all: only two decades after West Germany effectively swallowed the bankrupt East, two East Germans will be running the country.
We meet in historic times: Never before have the creative industries been so important to help take us through these difficult economic times And never before has the media been under such scrutiny because of the phone hacking scandal And all of this against the backdrop of astonishing developments in technology.
It has experienced astonishing growth and development over the past half-century, and nothing we saw indicates any loss of the spirit and hard work that have produced this.
Brilliant Corners was an astonishing mid-career development from Monk's move to the New York label Riverside.
