NASA稱，遙遠(yuǎn)的“太空雪人”幾乎沒有隕石坑，也沒有水

NASA稱，遙遠(yuǎn)的“太空雪人”幾乎沒有隕石坑，也沒有水

NASA’s space snowman is revealing fresh secrets from its home far beyond Pluto.

美國國家航空航天局(NASA)的“太空雪人”(space snowman)揭示了冥王星之外的新秘密。

More than a year after its close encounter with the snowman-shaped object, the New Horizons spacecraft is still sending back data from more than 4 billion miles away.

在與雪人形狀的物體近距離接觸一年多之后，新視野號(hào)宇宙飛船仍在從40多億英里外發(fā)回?cái)?shù)據(jù)。

“The data rate is painfully slow from so far away,” said Will Grundy of Lowell Observatory in Flagstaff, Arizona, one of the lead authors.

來自亞利桑那州弗拉格斯塔夫洛厄爾天文臺(tái)的威爾·格倫迪是這項(xiàng)研究的主要作者之一。

Astronomers reported Thursday that this pristine, primordial cosmic body now called Arrokoth — the most distant object ever explored — is relatively smooth with far fewer craters than expected. It’s also entirely ultrared, or highly reflective, which is commonplace in the faraway Twilight Zone of our solar system known as the the Kuiper Belt.

天文學(xué)家星期四報(bào)告說，這個(gè)原始的宇宙天體現(xiàn)在被稱為Arrokoth，是迄今為止被探索過的最遠(yuǎn)的天體，它的表面相對(duì)平坦，隕石坑比預(yù)期的要少得多。它也完全是紅外線的，或者說是高反射的，這在我們太陽系遙遠(yuǎn)的邊緣地帶——柯伊伯帶是很常見的。

Grundy said in an email that to the human eye, Arrokoth would look less red and more dark brown, sort of like molasses. The reddish color is indicative of organic molecules.

Grundy在一封電子郵件中說，在人眼看來，Arrokoth會(huì)少一些紅色，多一些深褐色，有點(diǎn)像糖蜜。紅色表示有機(jī)分子。

While frozen methane is present, no water has yet been found on the body, which is an estimated 22 miles long tip to tip. At a news conference Thursday in Seattle, New Horizons’ chief scientist Alan Stern of Southwest Research Institute said its size was roughly that of the city.

雖然有冰凍的甲烷存在，但球體上還沒有發(fā)現(xiàn)水，估計(jì)從頭到尾有22英里長。在周四于西雅圖舉行的新聞發(fā)布會(huì)上，新視野號(hào)的首席科學(xué)家、西南研究所的艾倫·斯特恩(Alan Stern)說，新視野號(hào)的大小與西雅圖差不多。

As for the snowman shape, it’s not nearly as flat on the backside as previously thought. Neither the small nor big sphere is fully round, but far from the flatter pancake shape scientists reported a year ago. The research team likened the somewhat flattened spherical forms to the shape of M&Ms.

至于雪人的形狀，它的背面并不像之前想象的那么平坦。小球體和大球體都不是完全圓的，但與科學(xué)家一年前報(bào)告的扁平的煎餅形狀相去甚遠(yuǎn)。研究小組將這種有點(diǎn)扁平的球形形狀比作m&m巧克力豆的形狀。

No rings or satellites have been found. The light cratering suggests Arrokoth dates back to the formation of the solar system 4.5 billion years ago. It likely was created by a slow, gentle merger between two separate objects that possibly were an orbiting pair. The resulting fused body is considered a contact binary.

沒有發(fā)現(xiàn)環(huán)或衛(wèi)星。這些隕石坑表明，Arrokoth可以追溯到45億年前太陽系的形成。它很可能是由兩個(gè)獨(dú)立的天體緩慢而溫和地合并而成，它們可能是軌道上的一對(duì)。由此產(chǎn)生的融合體被認(rèn)為是一個(gè)接觸二元體。

This kind of slow-motion hookup likely arose from collapsing clouds in the solar nebula, as opposed to intense collisions theorized to form these planetesimals, or little orbiting bodies.

這種慢動(dòng)作的連接很可能是由太陽星云的云的坍縮引起的，而不是理論上形成這些星子或小軌道天體的激烈碰撞。

The New Horizons scientists reported their latest findings at the annual meeting of the American Association for the Advancement of Science, as well as in three separate papers in the journal Science.

新視野號(hào)的科學(xué)家們?cè)诿绹茖W(xué)促進(jìn)會(huì)的年會(huì)上報(bào)告了他們的最新發(fā)現(xiàn)，同時(shí)也在《科學(xué)》雜志上發(fā)表了三篇獨(dú)立的論文。