Gwyneth Paltrow will soon light up candles for her 50th birthday.

But until then, she's reflecting on what this milestone means to her.

The Iron Man actress posted a black-and-white bikini photo on Instagram on Sept. 22.

Which she linked out to a lengthy personal essay about self-acceptance. 

She said she's feeling the weight of the moment as a time of growth and reflection.

She reflected on how aging has changed her body, the "silver hair and fine lines."

"My body, a map of the evidence of all the days, is less timeless," she wrote.

"Scarred from oven, a finger smashed in a window long ago, the birth of a child."

Paltrow, though, said she's accepted these signs of age on her body.

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