罗曼太空望远镜:NASA下一座“伟大天文台” 将于周日发射


2026-08-29T16:11:00-0400 / https://www.cbsnews.com/news/roman-space-telescope-nasa-launch-preview/

美国国家航空航天局(NASA)的罗曼太空望远镜搭载了一枚原本为间谍卫星制造的、尺寸与哈勃望远镜相当的镜面,将于周日发射升空。这项耗资43亿美元的任务将为人类打开观测宇宙的新窗口,它将拍摄广角超清晰图像,完整展示这些图像需要50万台4K电视。

换个角度来说,官方表示,罗曼望远镜3亿像素广角相机拍摄的单张全分辨率图像,可以覆盖45个城市街区,或是约塞米蒂国家公园内的酋长岩全貌。而且它的数据收集速度将超过NASA此前任何一艘航天器。

单张全分辨率图像可覆盖45个城市街区或整个酋长岩。

艺术家笔下的NASA43亿美元南希·格蕾丝·罗曼太空望远镜在距地球100万英里的轨道上运行。该望远镜计划于美国东部时间周日上午7点26分由SpaceX重型猎鹰火箭发射升空。 NASA

哈勃太空望远镜在30年的运行中传回了约172太字节的数据,而罗曼望远镜在其5年的主要任务期间,下行数据量将达到惊人的2500太字节。

换另一种方式来说,罗曼望远镜的高灵敏度广角相机和先进探测器将以比哈勃快1000倍的速度扫描广阔的宇宙空间,一个月内收集的数据量就相当于其“前辈”哈勃一个世纪的总量。

堪称“超强动力装置”的望远镜

NASA局长贾里德·艾萨克曼表示,海量数据有望为“暗物质、暗能量以及宇宙本身的结构”带来新认知,并加速发现太阳系外潜在宜居行星。

“罗曼望远镜将为地球绘制一份全新的宇宙地图,”他补充道。

NASA科学主管尼基·福克斯将该望远镜称为“一台超强动力装置”和“真正的速度机器”。

“我们扫描天空、传递海量数据并返回研究结果的速度将达到前所未有的水平,此前从未有过,”福克斯补充道。

搭载罗曼太空望远镜的SpaceX重型猎鹰火箭于周五夜间被转运至肯尼迪航天中心39A发射台,为发射做好准备。 NASA

这台长42英尺、重18000磅的望远镜以已故的南希·格蕾丝·罗曼命名,她是NASA首位首席天文学家,在其职业生涯中始终倡导太空望远镜的价值,并为哈勃太空望远镜的开发做出了重要贡献。因此,她常被称为“哈勃之母”。

这台新望远镜计划于美国东部时间周日上午7点26分,由三级芯级的SpaceX重型猎鹰火箭在肯尼迪航天中心发射升空。

它将前往拉格朗日L2点——一个位于地球背阳面约100万英里处的引力平衡点,在这里仅需极少燃料就能保持轨道位置。詹姆斯·韦伯太空望远镜也因同样原因部署在该区域。

从拉格朗日L2点的观测位置出发,罗曼望远镜将研究暗物质的影响。暗物质是一种遍布宇宙的神秘物质,它将星系凝聚在一起,占据了宇宙中大部分质量,同时还会抑制宇宙膨胀——而宇宙膨胀正让星系之间的距离越来越远。

与此同时,罗曼望远镜将帮助科学家们对暗能量的本质获得具有统计显著性的认知。暗能量是一种与引力相反的斥力,据推测自大爆炸以来就存在,约50亿年前随着宇宙膨胀和物质密度降低而占据主导地位。自那以后,宇宙膨胀的速度一直在加快。

罗曼太空望远镜的7.9英尺宽镜面原本为一颗机密间谍卫星制造,后由国家侦察局捐赠给NASA,原项目随后被取消。 NASA

对宇宙的全新认知

罗曼望远镜可能有助于解决一项矛盾:通过探测大爆炸遗留的3K宇宙微波背景辐射测得的早期宇宙暗能量强度,与哈勃望远镜通过观测特定类型超新星得到的结果略有不同。

1990年哈勃望远镜发射时,科学界对宇宙年龄——从大爆炸诞生至今——的估算范围在100亿年到200亿年之间。

哈勃望远镜确定了宇宙膨胀的速度——哈勃常数,并将大爆炸至今的时间精度控制在1%以内:138亿年。

但使用探测器研究大爆炸余晖——3K宇宙微波背景辐射的研究人员得出了不同的数值。这种差异被称为“哈勃张力”,表明当前对宇宙的认知中可能缺失了某些关键要素,或是对驱动宇宙演化的力量理解有误。

“我们看到的证据表明,从极早期宇宙推断出的哈勃常数,与我们在更近时期测得的数值并不一致,这说明连接这两者的模型可能并不完全正确,”项目科学家朱莉·麦克恩里说道。“我们在宇宙结构应该如何生长和演化的预期上存在细微的张力。”

这种“细微张力”暗示着标准宇宙学模型——当前对宇宙及其内所有事物演化的认知——可能存在潜在的严重缺陷。它甚至可能表明,暗能量并非如目前所认为的那样是恒定不变的,而是可能随时间发生变化。

罗曼望远镜主镜的光线会经过另外两面反射镜反射,最终到达红外焦平面探测器,也就是图中展示的设备。这些探测器让罗曼望远镜拥有了相当于3亿像素的红外相机。 NASA

“我们可能不会证实当前的宇宙标准模型,”麦克恩里说道。“我们很可能会证明现有的标准模型是错误的,并为我们找到宇宙真正的运行方式铺平道路。很难找到比‘宇宙的本质是什么’更基础的问题了!”

罗曼望远镜的广角相机是航天器上搭载的两台仪器之一。另一台是先进日冕仪,配备了可变形镜面,能够遮挡恒星的强光,从而探测到围绕恒星运行的行星反射的微弱光线。

罗曼望远镜的日冕仪有望探测到围绕类太阳恒星运行的木星大小行星。通过分析反射光线,研究人员可以推断出这些行星大气层的元素组成。

“我们认为我们有能力探测到比恒星暗1亿倍的系外行星,凭借这一能力,我们希望首次通过可见光观测到附近恒星周围的木星孪生行星——利用其云层顶部反射的光线,”喷气推进实验室的罗曼日冕仪仪器科学家凡妮莎·贝利说道。“随后我们就可以利用这些光线研究其大气层的组成。”

迄今为止,人类已经利用NASA开普勒太空望远镜等小型设备发现了约6200颗系外行星。罗曼望远镜预计在18个月的观测中发现超过10万颗系外行星。

航天器需要3到4个月的时间进行“调试”,校准仪器并测试无数个子系统,之后才能正式开展科学运营。

这台由太阳能供电的罗曼望远镜以一面7.9英尺宽、410磅重的主镜为核心。这面镜子是国家侦察局捐赠给NASA的两面镜子之一——国家侦察局是管理美国众多高端间谍卫星的秘密机构。

这两面与哈勃望远镜尺寸相同的镜面原本为一项机密项目制造,后项目被取消。但两面镜子都被研磨到了近乎完美的精度,原本用于向下观测地球,而非向外观测深空。

NASA没有使用第二面镜子的计划或资金,而是专注于建造单台“旗舰”天文台。

已故的南希·格蕾丝·罗曼是NASA首位首席天文学家,在其漫长的航天生涯中始终倡导太空望远镜的价值。 NASA

捐赠的镜面的曲率、光滑度和抛光度都必须进行改造,以满足天文观测的要求,同时望远镜的桁架和其他组件也需要调整,使其能够承受拉格朗日L2点的超低温环境。

“我认为我们的工程团队觉得,我们收到了一套经过良好测试的部件,其中包括高度校准的光学系统,”项目经理杰基·汤森说道。“但我们实际上必须从头开始,进行定制改造,才能让它在我们的工作温度下正常运行。”

最终,该项目提前完成且预算未超支。但即便主镜是“免费”获得的,这台望远镜在5年主要任务期间的建造、发射和运营总成本仍将达到约43亿美元,由纳税人承担。

广阔的天空视野

罗曼望远镜计划在其5年任务期间开展三项“核心”巡天项目。

高纬度广角巡天将聚焦银河系平面之外的大片天空——覆盖整个天空的12%——避开银河盘面遮挡视线的星云和尘埃。其目标是编目超过10亿个星系的分布。

这项耗时520天收集的数据,将帮助研究人员更好地理解暗物质和暗能量如何在宇宙时间尺度上共同作用,推动宇宙结构的演化。

高纬度时域巡天将在两年内耗时180天进行观测。望远镜将反复对90个满月大小的同一区域成像,制作“电影”记录各种短暂天文事件,从超新星爆发到恒星坠入黑洞时释放的辐射。

麦克恩里将这类瞬变事件描述为“夜空中转瞬即逝的怪事”。

银球时域巡天将聚焦银河系核心——恒星、气体和尘埃组成的中央凸起区域,这里的超大质量黑洞会影响附近恒星的运行轨迹。

罗曼望远镜将对8.5个满月大小的区域进行成像,通过观测数亿颗恒星,寻找“微引力透镜”现象的迹象——背景恒星的光线会被 intervening天体的引力增强或放大——从而发现数万颗系外行星。

任务团队还为三项核心巡天未覆盖的“通用天体物理学”课题预留了观测时间。首个此类项目名为银盘巡天,将从头到尾监测银河系盘,覆盖面积达3455个满月。

该项目将对约200亿颗恒星进行绘图,提供有史以来最完整的银河系及其结构的肖像。

“最让我对罗曼望远镜感到兴奋的是它的发现潜力,”麦克恩里说道。“我们将观测20亿个星系,其中会有2000个百万分之一级别的罕见天体。我们将以极高的灵敏度随时间观测大片天空。我们会发现夜空中更多转瞬即逝的怪事。

“我非常希望,甚至可以说预期,罗曼望远镜最令人兴奋的科学发现将是我们未曾预料到的惊喜。这将为未来的任务提出更深刻的问题铺平道路。”

Roman Space Telescope, NASA’s next “great observatory,” poised for Sunday launch

2026-08-29T16:11:00-0400 / https://www.cbsnews.com/news/roman-space-telescope-nasa-launch-preview/

Using a donated Hubble-class mirror originally built for a spy satellite, NASA’s Roman Space Telescope is poised for launch Sunday on a $4.3 billion mission to open a new window on the universe, taking wide-angle, ultra-sharp images that would require a half million 4K TVs to show in full.

Put another way, officials say a single full-resolution image from Roman’s 300-megapixel wide-field camera would cover 45 city blocks or the entirety of El Capitan inYosemite National Park. And it will collect that data faster than any previous NASA spacecraft.

An artist’s impression of NASA’s $4.3 billion Nancy Grace Roman Space Telescope on station a million miles from Earth. Launch atop a SpaceX Falcon Heavy rocket is targeted for 7:26 a.m. EDT on Sunday. NASA

The Hubble Space Telescope has beamed back about 172 terabytes of data over 30 years while Roman will downlink a staggering 2,500 terabytes over its five-year primary mission.

Put yet another way, Roman’s sensitive wide-field camera and advanced detectors will scan broad swaths of the cosmos 1,000 times faster than Hubble, collecting as much data in one month as its older cousin could manage in a century.

A “sheer powerhouse” of a telescope

The flood of data is expected to shed new light on the nature of “dark matter, dark energy and the structure of the universe itself and accelerate the … discovery of potentially habitable planets outside our solar system,” said NASA Administrator Jared Isaacman.

“Roman will give the Earth a new atlas of the universe,” he added.

NASA science chief Niki Fox described the telescope as “a sheer powerhouse” and “literally a speed machine.”

“The speed at which we’ll be scanning the sky, delivering vast amounts of data and returning results will be at an unprecedented rate, never done before,” Fox added.

A SpaceX Falcon Heavy carrying NASA’s Roman Space Telescope was hauled to pad 39A at the Kennedy Space Center overnight Friday to set the stage for launch. NASA

The 42-foot-long, 18,000-pound telescope is named for the late Nancy Grace Roman, NASA’s first chief astronomer, who championed the value of space telescopes throughout her career and was instrumental in the development of the Hubble Space Telescope. As such, she is often referred to as “the mother of Hubble.”

The new telescope is scheduled for launch atop a triple-core SpaceX Falcon Heavy rocket at the Kennedy Space Center at 7:26 a.m. EDT on Sunday.

It is bound for Lagrange Point No. 2 (L2), a gravitational eddy of sorts about a million miles on the opposite side of Earth from the Sun, where it will remain in place with minimal use of fuel. The James Webb Space Telescope is stationed in the same region for the same reason.

From the vantage point of L2, Roman will study the effects of dark matter, the mysterious substance that pervades the universe, holds galaxies together and accounts for most of the mass in the cosmos, acting as a brake on the expansion of space itself, which is carrying galaxies farther and farther apart.

At the same time, Roman will work to gain statistically significant insights into the nature of the equally mysterious dark energy, a repulsive force presumably present since the Big Bang that became dominant about 5 billion years ago as the universe expanded and thinned out. Ever since, the expansion of the cosmos has been speeding up.

Built for a classified spy satellite, the Roman Space Telescope’s 7.9-foot-wide mirror was donated to NASA by the National Reconnaissance Office when the original program was canceled. NASA

A new understanding of the universe

Roman may help resolve a conflict between the strength of dark energy in the very early universe, as measured by probes studying the remnant 3-degree glow of the Big Bang’s immediate aftermath, compared to Hubble observations of a specific type of supernova that indicate a slightly different value.

When the Hubble Space Telescope was launched in 1990, estimates for the age of the universe, from its Big Bang birth to the present, ranged from about 10 billion years to 20 billion years.

Hubble was able to determine the speed of that expansion — the Hubble Constant — and thus the time that has passed since the Big Bang to an accuracy within 1%: 13.8 billion years.

But detailed studies by researchers using spacecraft studying the afterglow of the bang — the 3-degree cosmic background radiation — came up with a different number. The mismatch — known as “the Hubble Tension” — suggests some critical element is missing in the current understanding of the universe and the forces driving its evolution.

“We’re seeing evidence that the Hubble constant, as inferred from very early times, is not consistent with the Hubble constant that we measure closer to now, which is telling us that the model that connects those two things might not be quite right,” said project scientist Julie McEnery. “We have a slight tension in our expectations for how structure should grow and evolve.”

That “slight tension” indicates a potentially serious flaw in the standard model of cosmology, the current understanding of how the universe, and everything in it, has evolved. It might even indicate dark energy is not the constant force it is thought to be, but might somehow change over time.

Light from Roman’s primary mirror will be reflected by two other mirrors before reaching the infrared focal plane detectors seen here. The detectors give Roman what amounts to a 300-megapixel infrared camera. NASA

“We’re probably not going to confirm the standard model of how the universe works,” McEnery said. “We’re very likely to demonstrate that our standard model is wrong, and to set ourselves on a path to figuring out how does our universe really work. It’s hard to get [a better question than] the fundamental nature of your universe!”

Roman’s wide-field camera is one of two instruments aboard the spacecraft. The other is an advanced coronagraph equipped with deformable mirrors that can block out the glare of a star to detect the vastly dimmer light reflected from the atmosphere of an orbiting planet.

Roman’s coronagraph is expected to detect Jupiter-size planets orbiting Earth-like stars. By analyzing that reflected light, researchers may be able to tease out the elemental composition of those atmospheres.

“We think that we will be capable of detecting exoplanets that are about 100 million times fainter than their stars, and with that capability, we are hoping to see … a Jupiter twin around a nearby star using visible light reflected from its cloud tops for the first time,” said Vanessa Bailey, the Roman coronagraph instrument scientist at the Jet Propulsion Laboratory. “Then, we can use that light to study the composition of its atmosphere.”

About 6,200 exoplanets have been discovered to date using smaller instruments like NASA’s Kepler Space Telescope. Roman is expected to discover more than 100,000 exoplanets over 18 months of observations.

It will take three to four months to “commission” the spacecraft, calibrating its instruments and testing its myriad subsystems before science operations can begin in earnest.

The solar-powered Roman is built around a 7.9-foot-wide, 410-pound primary mirror — one of two donated to NASA by the National Reconnaissance Office, the secretive agency that manages many of the nation’s high-end spy satellites.

The mirrors, the same size as Hubble’s, were built for a classified project that later was canceled. But both were ground to near-perfect prescriptions, allowing them to look down and focus on Earth, not out into deep space.

NASA has no plans or funding to utilize the second mirror, focusing instead on building a single “flagship” observatory.

The late Nancy Grace Roman, NASA’s first chief astronomer, championed the value of space telescopes throughout her long career at the space agency. NASA

The donated mirror’s curvature, smoothness and polish had to be modified to ensure the desired astronomical prescription, and the telescope’s trusses and other components had to be altered to enable them to withstand the ultra-low temperatures at Lagrange Point 2.

“I think our engineering team thinks of it as we received a set of well-tested parts that included highly calibrated optical systems,” said project manager Jackie Townsend. “But we really had to sort of start over and make it our own to work at our operating temperatures.”

In the end, the project came in ahead of schedule and under budget. But even with an effectively “free” primary mirror, the telescope will still cost taxpayers some $4.3 billion to build, launch and operate for its five-year primary mission.

A wide view of the sky

Three “core” surveys are planned over the course of Roman’s planned five-year mission.

The High-Latitude Wide-Area Survey will focus on a huge swath of the sky looking out of the plane of the Milky Way — 12% of the entire sky — avoiding obscuring star clouds and dust marking the galactic disk. The goal is to catalog the distribution of a billion or more galaxies.

Those data, collected over 520 days, will help researchers better understand how dark matter and energy have combined over cosmic time to drive the evolution of structure in the universe.

The High-Latitude Time-Domain Survey will require 180 days of observations over two years. The telescope will repeatedly image the same regions in an area of 90 full moons to make movies capturing short-duration events ranging from supernova blasts to the radiation emitted when stars fall into black holes.

McEnery described such transient events as “things that go bump in the night.”

The Galactic Bulge Time-Domain Survey will focus on the core of the Milky Way, the central bulge of stars, gas and dust where a supermassive black hole affects the trajectories of nearby stars.

Imaging across an area spanning 8.5 full moons, Roman is expected to find tens of thousands of exoplanets by watching hundreds of millions of stars and looking for signs of “microlensing,” a phenomenon in which the light of a background star is enhanced, or magnified, by the gravity of an intervening object.

Mission managers have also left room for “general astrophysics” topics not covered in Roman’s three core surveys. The first such program, known as the Galactic Plane Survey, will monitor the disk of the Milky Way from one side to the other, covering an area of 3,455 full moons.

Some 20 billion stars will be mapped along the way, providing the most complete portrait of the galaxy and its structure ever captured.

“What makes me most excited about Roman is the discovery potential,” McEnery said. “With 2 billion galaxies, we’ll have 2,000 objects that are one in a million. We’ll be exploring patches of sky as a function of time with exquisite sensitivity. We’ll find new things that go bump in the night.

“I very much hope, and in fact expect, that the most exciting science from Roman will be a surprise, something we couldn’t predict. And that will set the stage for the next deeper set of questions for future missions to address.”

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