NASA’s InSight spacecraft, the first robotic lander designed to study the deep interior of a distant world, touched down safely on the surface of Mars on Monday with instruments to detect planetary seismic rumblings never measured anywhere but Earth.
Engineers at the Jet Propulsion Laboratory (JPL) near Los Angeles burst into cheers, applause and hugs as they received signals confirming InSight’s arrival on Martian soil — a vast, barren plain near the planet’s equator — shortly before 3pm EST. Minutes later, JPL controllers received a fuzzy “selfie” photograph of the probe’s new surroundings on the Red Planet, showing the edge of one lander leg beside a rock.
InSight’s descent and landing, consisting of about 1,000 individual steps that had to be flawlessly executed to achieve success, capped a six-month journey of 548 million km from Earth. The spacecraft was launched from California in May on its nearly US$1 billion mission. It will spend the next 24 months — about one Martian year — collecting a wealth of data to unlock mysteries about how Mars formed and, by extension, the origins of the Earth and other rocky planets of the inner solar system.
Photo: REUTERS
照片:路透
“The reason why we’re digging into Mars is to better understand not just Mars, but the Earth itself,” said JPL’s Bruce Banerdt, InSight’s principal investigator. A central question is why Mars, once a relatively warm, wet planet, evolved so differently from Earth into a mostly dry, desolate and cold world, devoid of life. The answers are believed to have something to do with the as-yet unexplained absence, since Mars’ ancient past, of either a magnetic field or tectonic activity, said NASA’s chief scientist James Green. While Earth’s tectonics and other forces have erased most evidence of its early history, much of Mars — about half the size of Earth — has seemingly remained largely static, creating a geologic time machine for scientists, Green said.
InSight’s name is short for Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport. Its primary instrument is a French-built seismometer, designed to record the slightest vibrations from “marsquakes” and meteor impacts around the planet. The device, to be placed on the surface by the lander’s robot arm, is so sensitive it can measure a seismic wave just one half the radius of a hydrogen atom. Scientists expect to see a dozen to 100 marsquakes during the mission, producing data to help them deduce the depth, density and composition of the planet’s core, the rocky mantle surrounding it, and the outermost layer, the crust.
A second instrument, furnished by Germany’s space agency, consists of a drill to burrow as much as 5m underground, pulling behind it a rope-like thermal probe to measure heat flowing from inside the planet. A radio transmitter will send back signals tracking Mars’ subtle rotational wobble to reveal the size of the planet’s core and possibly whether it remains molten.
Photo: REUTERS
照片:路透
The landing data and initial photograph were relayed to Earth from two briefcase-sized satellites that were launched along with InSight and were flying past Mars as it reached its destination.
(Reuters)
美國國家航空暨太空總署為深入研究火星內部所打造的首具機器人探測器──「洞察號」太空船──週一平安降落在火星表面。「洞察號」配備多項儀器,將用來偵測未曾於地球以外測量到的行星地震。
在美東時間下午三點前不久,位於洛杉磯附近的噴射推進實驗室收到訊號,確認「洞察號」抵達火星地表,降落在該行星赤道附近一片廣闊而荒蕪的平原。工程師們當下爆出歡呼與掌聲,互相擁抱慶賀。幾分鐘後,實驗室的控制人員收到探測器傳來一張模糊的「自拍」,展示它在紅色行星上的新環境,還拍到一隻腳的邊緣出現在岩石旁邊。
「洞察號」的完美落地,為這趟長達六個月、距離地球五億四千八百萬公里的長途旅行漂亮收尾。降落和著陸的整段過程約由一千個獨立步驟組成,每一項都必須執行得毫無瑕疵才能成功。太空船今年五月自加州發射升空,展開這項斥資近十億美元的任務。「洞察號」將會在接下來的二十四個月──大約是火星的一年──蒐集豐富資料,為科學家解開火星形成的謎團,並藉此衍伸推論出地球和內太陽系其他岩石行星的起源。
噴射推進實驗室的「洞察號」首席調查員布魯斯‧班納特指出:「我們鑽研火星的原因,並不只是想要多了解火星,更是為了進一步了解地球本身。」核心問題在於,火星這顆曾經相對溫暖而潮濕的行星,為什麼會和地球的演變如此大相逕庭,成為絕大部分地區既乾燥又荒涼寒冷的世界,杳無生機。美國太空總署的首席科學家詹姆斯‧葛林表示,這個問題的答案據信與火星自古以來就消失無蹤的磁場或板塊運動有關,這些現象到現在都無法獲得解釋。葛林指出,地球上的板塊構造運動和其他外力幾乎抹去行星古早歷史的絕大部分證據;不過,大小約為地球一半的火星,大部分的地區似乎在多數時間中維持靜止,成為科學家的地質學時光機。
「洞察號」的全名是「運用地震調查、測地學以及熱傳遞學的內部探索(器)」。探測器配備的主要儀器是一台法國製造的地震儀,能夠記錄行星上發生「火星地震」和隕星撞擊所致最輕微程度的震動。該儀器將會由登陸器的機器人手臂放在地表,靈敏程度能夠測到長度僅為氫原子半徑再減半的震波。科學家預期於任務期間內觀察到十至一百次的「火星地震」,獲得足夠數據協助他們推論行星核心的深度、密度和組成物,還有包裹地核、如磐石般堅硬的地函,以及最外層的硬殼。
第二台儀器則由德國太空中心所提供,其中包括一只能夠挖到地底五公尺深處的鑽頭,後面牽著一條繩索狀的熱探測器,用來測量從行星內部向外流動的熱能。在此同時,一台無線電發射機將會回傳訊號,藉由追蹤火星輕微的旋轉軸晃動以揭露地核大小,或許也會透露出地核是否仍處於熔融狀態。
降落數據和最初的照片由兩台尺寸如公事包大小的人造衛星接力傳回地球。兩台人造衛星當初跟「洞察號」一同發射,但在抵達目的地火星後,還會繼續向外飛。
(台北時報章厚明譯)
The strongest earthquake to hit Taiwan in 25 years killed at least 16 people and damaged dozens of buildings, but the destruction was largely contained thanks to decades of preparedness work. Taiwan sits on the “Ring of Fire,” an arc of intense seismic activity along the Pacific Rim, and — much like neighboring Japan — has a long history of catastrophic quakes. How does April 3 compare with other recent quakes? The April 3 earthquake, which measured 7.4 on the moment magnitude scale, was felt across Taiwan. It was the most severe since a 7.6 magnitude quake in 1999 killed
Around the time of the Dragon Boat Festival in June, the streets of Taiwan are filled with the delightful aroma of zongzi, a traditional snack made of sticky rice wrapped in leaves. The leaves are folded into a cone and then filled with sticky rice and other ingredients such as braised pork belly, peanuts and salted duck egg yolks. The filled leaves are then tightly tied with kitchen twine and ready for cooking. 每到六月端午時節,街頭巷尾就會飄出粽子的香氣。粽子是將糯米包進粽葉的傳統美食,先將粽葉折成圓錐狀塞入糯米,以及紅燒肉、花生、鹹鴨蛋黃等配料,用棉線綁緊後即可烹煮。 Dragon Boat Festival (n. phr.) 端午節 aroma
Everyone has seen a piece of fruit turn brown after being cut. Have you ever wondered why that happens? It is a common phenomenon that occurs due to a chemical reaction called enzymatic browning. The appearance, flavor and nutritional value of the fruit are all affected by this reaction. Some fruits, such as apples, pears, bananas, avocados and peaches, are more prone to enzymatic browning than others. These fruits contain high levels of an enzyme called polyphenol oxidase, or PPO for short. __1__ This causes a chain of chemical reactions that ultimately transforms the phenolic compounds into
A: Artificial intelligence technology has been causing controversy lately: a student was caught cheating with AI to win the grand prize in an art contest. B: That’s so absurd. Does this mean that AI paints better than humans? A: Maybe. Luckily, the student was later disqualified. B: And more absurdly, it’s becoming more and more popular to use AI technology to “resurrect” people. A: Yeah, some netizens even posted videos featuring the late singer CoCo Lee, who was “resurrected” by them with AI software. A: 人工智慧的爭議不斷,有學生違規使用AI參加美術展,甚至贏得首獎。 B: 真誇張,這是不是代表AI比人類還強大? A: 或許吧,幸好得獎資格被取消。 B: 還有更誇張的︰讓死者重現的「AI復活」技術越來越熱門。 A: 對啊,還有網友製作已故歌后李玟「復活」的影片呢! (By Eddy Chang, Taipei Times/台北時報張聖恩)