科学政策

How do you clean up 170 million pieces of space junk?

05.24.23 | 6 min read | 文字维杰·艾耶(Vijay Iyer)

In March, NASA released the most comprehensivefinancial analysis on space debris. For the first time, this report illuminates the financial costs and benefits of various paths forward to combat one of the fastest-growing dangers in Earth’s orbit.

太空经济是巨大的,但其最大的挑战之一是很小的:太空碎片,在那里,与物体的碰撞甚至镍的大小也会造成灾难性的损害。现在将更多的物体放入轨道上,而不是历史上的任何时刻。这增加了卫星与现有碎片之间发生碰撞的机会。从立法/监管工作到技术方面的碎片,已经采取了不同的方法来管理和减轻碎片。

With increased activity in space, debris is a growing threat to Low Earth Orbit (LEO), the most accessible area of space. There may be as many as170millionpieces of debrisin orbit, with the vast majority too small to track due to limits in current technology, but no less dangerous. Of the55,000 pieces我们可以跟踪的碎屑,有27,000多个物体,例如用过的火箭助推器,活跃的卫星和死卫星,都受到监视Department of Defense’s global Space Surveillance Network (SSN).

由于物体在狮子座中移动的速度(大约17,000英里 /小时), the impact of even a small object, like a乒乓球, can cause significant damage or completely shatter existing infrastructure, producing more fragments of trackable and detectable size. Twice in the last month, theInternational Space Station had to perform maneuvers躲避碰撞。除了立即的狮子座拥塞外,凯斯勒综合症,当前碎片创建一个成长和self-replicating cascade of orbital junk, is also a growing possibility. Political leaders have begun to pay attention: Sen. John Hickenlooper (D-CO)–one of the leaders in Congresson this issue–has said “Because of the threats from debris already in orbit, simply preventing more debris in the future is not enough.”

缓解方法

Technological efforts to limit debris include making reusable rockets and maneuverable satellites. Certain satellites can adjust their position through a satellite operator, a person or entity that manages a satellite. For example, the International Space Station performed what is called anin-orbit maneuverto dodge debris. To meet the needs of clean-up, industries have developed debris-cleaning tech like ground laser nudges, space tugs, and space lasers. Policy has not随着快速增长的步伐of the emerging commercial space industries. Industries are also hesitant to use and effectively implement new technologies because costs have been uncertain.

There has never been a comprehensive cost-benefit analysis of debris clean-up (remediation) methods despite robust data on the number of objects in space being available. This new NASA analysis provides the cost of tech and the time to recover the costs, giving industries a better idea of how to implement new technologies effectively.

为了创建报告,NASA科学家创建了一个模型,该模型根据符合清理成本所需的时间以及所使用的清理方法来指定对卫星运营商施加的经济风险碎片。然后,科学家将模型应用于两种情况:优先考虑大量碎片分解和清除碎片(又称空间中最大,最容易受到关注的物体),并瞄准去除小碎屑(消除了100,000块碎屑,从1-10厘米的1-10 cm In In In In In尺寸)。

度均nt Methods of Debris Management Technology

碎片管理方法 Application to Debris Size Description 估计成本(低) 估计成本(高) Development Costs
拖船进行控制的再入 大(≥10厘米) 捕获一个物体并调节其轨道,以便以特定角度重新进入大气,以使浓缩区域中的碎屑崩溃。 ~$4,000 per kilogram ~$60,000 per kilogram n/a
拖船进行不受控制的再入 Large (≥10 cm) Catch an object and adjust its orbit so it re-enters the atmosphere freely with no predesignated fall area and unclear reentry timing. 〜每公斤$ 3,000 ~$40,000 per kilogram n/a
Ground Laser Nudges Large (≥10 cm), Small debris (1 cm–10 cm) Uses a laser to move an object without physical contact from the surface of the Earth. Requires a lot of energy. ~$300 per kilogram ~$6,000 per kilogram ~$600 million
太空激光轻推 Large (≥10 cm), Small debris (1 cm–10 cm) Uses a laser to move an object without physical contact from space. Uses less energy from ground-based lasers since much of the energy won’t be lost going through the atmosphere. ~$300 per kilogram 〜每公斤$ 3,000 〜3亿美元
通过激光轻推(JCA)的及时碰撞(JCA) Large (≥10 cm) Used to prevent predicted collisions between large pieces of orbital debris, like satellites and debris by informing laser nudges. 100千克对象的$ 6介于每辆车上的9,000千克对象$ 500 100千克对象的$ 700之间 - $ 60,000-每一个机动的9,000千克对象 n/a
Just-in-time collision avoidance (JCA) via Rapid Response Rockets Large (≥10 cm) Used to prevent predicted collisions between large pieces of orbital debris, like satellites and debris by informing Rapid Response Rockets(RRR). These rockets would meet with specific debris and alter the target debris’ orbit. $30 million per nudge $60 million per nudge n/a
Physical Sweeping Large (≥10 cm), Small debris (1 cm–10 cm) 直接影响碎屑移动或搬迁。 $90,000 per kilogram 每公斤900,000美元 $90,000 million
回收碎片 Large (≥10 cm) Gathering and processing debris and processing it in space to use as fuel or other utilities. ~$1.4 billion at 15,000/kg n/a n/a

三个关键发现

寻找1.为了降低操作员的风险,应清除小碎片,应将大碎片轻轻降低以防止碰撞。

Even though it is initially expensive, removing small debris would produce a net benefit in under a decade:

NASA报告图ES-3

初始投资可以快速整理,并产生很大的影响。

NASA报告图ES-2

初始投资可以快速整理,并产生很大的影响。

NASA的模型表明,除去不可痕迹的碎片的碎片清除工作可以立即带来好处。对于可追踪的碎片,弥补初始成本只需3 - 4年。

Finding 2. Spacecraft operators can recover the initial upfront cost quickly using reusable technologies that clean up debris using controlled and uncontrolled reentry.

NASA报告图ES-1

与删除大物体相关的利益每年在修复后每年都会增长。

For the 50 largest objects in space, which can be effectively removed using controlled re-entry, especially when done using reusable vehicles, cost recovery would be seen in around three decades.

Finding 3. Recycling space debris does not provide overwhelmingly clear enough financial benefits over other debris cleanup methods.

While there are potential economic and climate benefits to recycling space debris, recycling in space reduces the risk of有害化学物质being released into the upper atmosphere as it burns upon reentry and limits the amount of debris remnants in the upper atmosphere.

Investing in debris recycling facilities has a large upfront cost, and it is not guaranteed that a market for such facilities will emerge in the next decade. This makes projections for the value of recycling uncertain. The report indicates, however, that debris recycling is a potential solution to long-term efforts of debris management. This can be done throughin-space manufacturing and assembly(ISAM), a practice that involves factories and utility services in space and covers servicing, assembly, and manufacturing. These facilities can be used to收集并回收数十亿美元价值空间碎片的美元,并帮助创建“圆形空间经济”使用现有碎片处理,回收,建造和加油空间基础设施。

三个解决方案

我们的想法已经有助于解决空间碎片。第一天项目贡献者林德西·格雷(Lyndsey Gray)outlined five policy solutions to space debris remediation. Highlighted below are the three most relevant ones below:

建议1. NASA的轨道碎片计划办公室(ODPO)与国防部的太空监视网络协调,应在Leo中创建优先的大量空间碎片物品清单,以加快清理工作。

This is a strong start. Creating a list of large debris (>10 cm) by impact and prioritizing nudging large debris like non-functioning satellites, spent rocket stages, and other large debris using ground lasers will allow increased benefits for less cost. Additionally, NASA should prioritize destroying non-trackable and other small debris.

Their report finds that remediating smaller debris not only demonstrates results faster but is a lighter financial lift. Surveying debris size and impact can be done alongside removing smaller debris, maximizing impact.

Recommendation 2. The Space Force, in collaboration with the Department of Commerce (DOC), should fund removal and/or recycling of a set number of large debris objects each year, thereby creating a reliable market for space debris removal.

We recommend that the nascent Space Force and Department of Commerce provide funding for technical solutions to remove and recycle larger debris objects. If we are to tackle the space debris problem at all, we need funding. The amount of large debris is already extensively cataloged. This is doable with the completion of a trackable list of large debris from Recommendation 1.

NASA的报告提供了成本信息,以激发新兴太空行业的精力,以开始投资清除碎屑工具和基础设施以最大程度地发挥影响力。NASA指出,预计的预计碎屑的预期/保养成本以及清除大碎片的成本。由于可以通过轻推可节省更多的钱,并且仍然可以有意义地防止碰撞,因此这可以为开发ISAM回收功能提供空间。

建议3. NOAA的太空贸易办公室与太空部队和NASA的ODPO结合,应共同发布一份年度研究报告,概述风险,成本效益分析以及轨道碎屑清除和回收的经济学。

进行定期的成本效益分析可以帮助企业评估自己的回收和空间碎片清理工作的范围。NASA的成本效益分析与该建议的意图保持一致。NASA的报告也为将来的重复分析提供了良好的基础。

What Next?

Space debris isn’t going to go away, but we can start minimizing the threat it poses.

The NASA report indicates that taking action immediately will have minimal financial drawbacks, with a high debris-cleaning impact within a few years. Technologies like ground and space laser nudges provide low-cost alternatives to other debris mitigation methods currently in use. The report also provides insight into industries’ understanding of the true financial costs associated with cleaning space debris. This can incentivize innovation and create even more cost-effective technologies to manage and clean up debris. There is also an immediate need to address the space debris problem: existing U.S. government and commercial infrastructure (the International Space Station and commercial internet and science satellites) is at risk. The faster space debris is addressed, the more space innovation and invention we will see in the coming decades.