By the time Dragonfly reaches Titan in 2034, it has been almost 30 years since Saturn’s satellite was last visited by a spacecraft.

英訳に間違いが有れば正してください。

2034年にドラゴンフライがタイタンに到着する頃には、土星の衛星が最後に宇宙船に訪問されてから30年近くになることになる。
ドラゴンフライは探査機のこと
By the time Dragonfly reaches Titan in 2034, it has been almost 30 years since Saturn’s satellite was last visited by a spacecraft.

ヒント
ことになる

答え hasをwill haveにする

By the time Dragonfly reaches Titan in 2034, it will have been almost 30 years since Saturn’s satellite was last visited by a spacecraft.

時制の間違い。未来の話なので当然に未来形にする。

By the time Dragonfly reaches Titan in 2034, it will have been almost 30 years since Saturn’s satellite was last visited by a spacecraft.


引用元
New NASA Mission Will Fly Titan’s Frigid Skies to Search for Life’s Beginnings

https://www.scientificamerican.com