This is the 202nd most frequent Japanese word.
新た
"新た" means "new" or "fresh."
In this sentence, "新た" is used as an adjectival noun (na-adjective) to describe a new or additional challenge.
彼は新たな挑戦に取り組むことを決めました。
He decided to take on a new challenge.
Here, "新たに" functions as an adverb, indicating that the discovery of the facts was recent or novel.
新たに発見された事実が事件を解明する鍵となりました。
The newly discovered fact became the key to solving the case.
In this statement, "新た" as an adjectival noun emphasizes the novelty and originality of the perspective introduced.