Bima Sakti di Atas Glacier Point

Yosemite memiliki langit tergelap yang pernah dilihat sebagian besar pengunjung Amerika. Polly mendengar ini dari Tomas. Dia ingin melihatnya sendiri.

Yosemite has the darkest sky most American visitors ever see. Polly had heard this from Tomas. She wanted to see for herself.

Dia menunggu sepanjang sore di Glacier Point, sebuah tempat pandang 970 meter di atas dasar lembah. Sekelompok kecil orang berkumpul di sana untuk menyaksikan matahari terbenam. Polly duduk di pagar.

She waited out the afternoon at Glacier Point, an overlook 970 metres above the valley floor. A small crowd was there for the sunset. Polly perched on the railing.

Matahari terbenam di balik punggung Sierra. Half Dome, di seberang lembah, menangkap cahaya merah terakhir di wajahnya dan menahannya selama dua puluh detik. Kemudian cahaya merah itu menghilang. Kerumunan bertepuk tangan pelan.

The sun went down behind the Sierra ridge. Half Dome, across the valley, caught the last red light on its face and held it for twenty seconds. Then the red was gone. The crowd clapped softly.

Seorang astronom taman dengan rompi cokelat menyiapkan teleskop kecil. Dia memberikan ceramah sementara langit semakin gelap. Dia menjelaskan bahwa sebagian besar kota di Amerika telah kehilangan Bima Sakti karena lampu jalan. Namun di Yosemite, pada malam yang cerah, Anda masih bisa melihat apa yang telah dilihat manusia di sini selama ribuan tahun.

A park astronomer in a brown vest set up a small telescope. He gave a talk while the sky grew darker. He explained that most American cities have lost the Milky Way to streetlights. But in Yosemite, on a clear night, you can still see what humans have seen here for thousands of years.

Bintang pertama muncul satu per satu. Saat malam benar-benar gelap, Bima Sakti tampak seperti pita cahaya pucat melintasi langit. Pita itu terputus oleh bercak gelap di mana awan debu menghalangi bintang di belakangnya. Bercak gelap terbesar disebut Great Rift. Polly bisa melihatnya dengan jelas.

The first stars came out one at a time. By full dark, the Milky Way was a band of pale light running across the sky. It was broken by dark patches where dust clouds blocked the stars behind them. The biggest dark patch was called the Great Rift. Polly could see it clearly.

Astronom itu mengarahkan teleskop ke sebuah noda kecil di dekat Sagittarius. "Ini adalah pusat galaksi kita," katanya. "Lubang hitam supermasif di pusatnya berjarak dua puluh enam ribu tahun cahaya."

The astronomer pointed the telescope at a small smudge near Sagittarius. "This is the centre of our galaxy," he said. "The supermassive black hole at its heart is twenty-six thousand light years away."

Seorang pengunjung melihat melalui lensa, lalu mundur. Astronom itu memiringkan teleskop agar Polly juga bisa melihat. Melalui lensa terlihat kumpulan bintang dan debu yang padat.

A visitor looked through the eyepiece, then stepped back. The astronomer tilted the telescope so Polly could see in too. Through the eyepiece was a dense cluster of stars and dust.

Dua puluh enam ribu tahun yang lalu, cahaya yang meninggalkan kumpulan itu memulai perjalanannya ke teleskop ini. Polly melihatnya dalam waktu yang lama.

Twenty-six thousand years ago, the light leaving that cluster had started its trip to this telescope. Polly looked for a long time.