科学美国人60秒 SSS Ultima Thule and the Apes of Earth（在线收听）

Steve Mirsky: Welcome to Scientific American’s Science Talk, posted on January 3, 2019. Happy New Year! I’m Steve Mirsky.

Ultima Thule. It’s the little snowman–shaped Kuiper Belt object that the New Horizons mission flew by on January 1st. We’ll be receiving info about Ultima Thule from the spacecraft for the next 20 months or so. And there’s plenty of coverage about the mission and the object on our site and all over the web.

So for this short edition of Science Talk I want to focus on the deep-time aspect of Ultima Thule…and us. On New Year’s Eve, the Johns Hopkins University Applied Physics Laboratory hosted a few short talks about the latest stop for the New Horizons mission. The speakers were all space people. With the exception of Kenneth Lacovara. Who’s a paleontologist, based at Rowan University in New Jersey. Lacovara has found the remains of the largest-known dinosaurs. Including Dreadnoughtus, which weighed in at about 65 tons. Its femur is as tall as an NBA shooting guard.

Lacovara gave a brief talk for the Web cast New Year’s Eve that puts the study of Ultima Thule in a somewhat different context than we may usually think about space missions. I happened to be watching live and I grabbed the audio to share with you. Enjoy!

[applause]

Kenneth Lacovara:    Thank you. Thank you, Alan Stern and the New Horizons team for having me. This will be a night to remember.

                           You know, the past is out there. It's beneath our feet and in the heavens above. And we can learn from it. We should learn from it. "The further back you look, the further ahead you will see," Winston Churchill said. Indeed, we would all like to have access to the future but that's impossible. It's only the past that gives us predictive insight into what the future may hold. It's the past that is our guide. Who are we? Where did we come from? What is our place in space and time? These are the fundamental questions of the human condition that transcend culture and generations.

                           We can gain insight into these monumental, existential questions by traveling through time, into the Earth's crust, excavating the rocks and the bones of the many past worlds that have been our Earth. Or, we can travel to the further shores of our solar system and meet the past, as it lies preserved in the darkest, iciest outposts of our star's domain.

                           The New Horizons space probe rendezvous with Ultima Thule culminates tonight, in a poignant moment in the evolution of exploration as it encounters this ancient, mysterious voyager. New Horizons will transform from a journey into space into the journey into the depths of deep time. Like a fossil in the sky, Ultima Thule survives as a remnant of the earliest moments of our solar system. Frozen and pristine, it bears everlasting witness to both the cataclysms and the slow motion workings of worlds that have shaped the retinue of planets beneath.

                           Ultima Thule once shared the solar system with an Earth devoid of any living thing, a planet boiled and sterilized by incessant cosmic bombardment. When the worst of it ended life grabbed hold and never let go. For three billion years Ultima Thule circled the sun while nothing more complex than clumps of microbes agitated in our planet's primordial ocean. It was out there, floating in space when cells on Earth began to cooperate, building bodies, and grouping themselves into tissues. It arced through Cambrian skies when the major branches of the tree of life emerged from our common stock.

And when the lobe-finned fish climbed out from the seas it was there, tracing endless ellipses in the void. There, moving, always moving silently above when the dinosaurs were new and could terrorize nothing bigger than a bug. There, in the sky, over every muddy Spinosaurus, every quarrelsome Velociraptor, every bloodthirsty T. rex. And there, unbeknownst to every insatiable Dreadnoughtus, [laughter], when the reign of the dinosaurs came crashing down in a cosmic accident, it was there to witness the rise of the mammals, and the ascent of the apes, through which our solar system became aware of itself.

                           And now, after a long prelude, we "twins of the same womb" – to borrow a phrase from the poet, Marge Piercy, the apes of Earth and Ultima Thule, are set to meet in a most improbably rendezvous [laughter]. Tonight, like a paleontologist revealing a dinosaur bone and linking its existence to our own, New Horizons will drill into our ancient past as it flies by this tiny, frozen world and will glimpse a fossilized moment in time, a moment that led to the coalescence of our planets, to the transformation of geology into biology, and the evolution of spectacular and improbably creatures such as dinosaurs, and ourselves.

From this lonely vantage point near the ends of our solar systems, New Horizons will offer the world the humbling perspective that only deep time and deep space can provide as it digs like a pick axe in the sky into our wondrous past. Thank you. Congratulations

[applause]

Mirsky: Thanks to the John Hopkins Applied Physics Lab and to Ken Lacovara for green-lighting my use of their audio. We’ll be back in a few days with a more traditional episode of Science Talk. Til then, check out www.scientificamerican.com for our continuing coverage of the New Horizons mission and for all your science news.

And follow us on Twitter, where you’ll get a tweet whenever a new item hits the Web site. Our twitter name is @sciam. For Scientific American’s Science Talk, I’m Steve Mirsky, thanks for clicking on us.