Radio telescope tracking asteroid with radar waves.

Radar Vision: How Scientists Track Near-Earth Objects to Protect Our Planet

Samir D’Costa in Science & Nature September 2025 • 4 min read.

"Explore the cutting-edge technology and international collaboration that keeps Earth safe from potential asteroid impacts."

In a cosmic game of cat and mouse, scientists are constantly watching the skies, tracking asteroids and other near-Earth objects (NEOs) that could pose a threat to our planet. This isn't science fiction; it's a real and ongoing effort that combines advanced technology, international collaboration, and a healthy dose of vigilance.

Radar measurements are a primary tool in this endeavor, providing essential information about the size, shape, rotation, and orbital paths of NEOs. Think of it as giving our planet a pair of high-tech glasses, allowing us to see and understand these celestial bodies in greater detail. This data is crucial for assessing potential risks and planning any necessary defensive measures.

One of the key players in this global effort is the Institute of Applied Astronomy (IAA) of the Russian Academy of Sciences, which works in collaboration with the Goldstone Deep Space Communications Complex. Together, they conduct intercontinental radar observations of NEOs, utilizing powerful antennas and sophisticated software to gather and analyze data.

How Does Radar Technology Help Us Understand Near-Earth Objects?

Radio telescope tracking asteroid with radar waves.

Radar technology offers several critical advantages when studying NEOs. Unlike optical telescopes, which rely on sunlight, radar can penetrate the darkness of space and provide detailed information about these objects, regardless of lighting conditions. This is particularly important for detecting NEOs that might be difficult to spot visually.

The process involves bouncing radio waves off the surface of an NEO and analyzing the returning signal. By studying the characteristics of this echo, scientists can determine:

Size and Shape: Radar helps determine the dimensions and overall form of the NEO, providing insights into its physical properties.
Rotation: By analyzing the Doppler shift of the radar signal, scientists can measure the NEO's rotation rate and identify any complex rotational patterns.
Surface Features: Radar can reveal details about the NEO's surface, such as roughness, composition, and the presence of craters or other geological features.
Orbital Accuracy: Precise radar measurements help refine the NEO's orbital path, allowing scientists to predict its future trajectory with greater accuracy.

The collaboration between the IAA and the Goldstone Deep Space Communications Complex exemplifies the international effort to monitor NEOs. The IAA utilizes the RT-32 radio telescopes of the Quasar VLBI network, while Goldstone employs its 70-meter DSS-14 antenna as a transmitter. This "bistatic" approach, where transmission and reception occur at different locations, maximizes observation time and improves data quality.

Why Does This Matter?

The ongoing work of the IAA, the Goldstone Complex, and other institutions around the world is crucial for protecting our planet from potential asteroid impacts. By continuously monitoring NEOs, refining our understanding of their properties, and developing strategies for planetary defense, we can mitigate the risks and ensure the long-term safety of Earth.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1134/s0020441218030235, Alternate LINK

Title: A Complex For Carrying Out Radar Observations Of Near-Earth Objects

Subject: Instrumentation

Journal: Instruments and Experimental Techniques

Publisher: Pleiades Publishing Ltd

Authors: D. A. Marshalov, Yu. S. Bondarenko, Yu. D. Medvedev, D. E. Vavilov, M. B. Zotov, A. G. Mikhailov

Published: 2018-07-01

Everything You Need To Know

How does radar vision work to track near-Earth objects?

Radar vision uses radio waves to detect and characterize near-Earth objects (NEOs). Unlike optical telescopes that need sunlight, radar can penetrate the darkness of space. By bouncing radio waves off an NEO and analyzing the returning signal, scientists can determine its size, shape, rotation, surface features, and orbital accuracy. This detailed information helps in assessing the threat posed by the NEO.

Why is international collaboration important in tracking near-Earth objects?

International collaboration is essential for tracking NEOs because it allows for continuous monitoring and improved data quality. For example, the Institute of Applied Astronomy (IAA) of the Russian Academy of Sciences collaborates with the Goldstone Deep Space Communications Complex. The IAA uses RT-32 radio telescopes, while Goldstone uses its 70-meter DSS-14 antenna. This "bistatic" approach, where transmission and reception occur at different locations, maximizes observation time and enhances the precision of the data collected.

Why is knowing the size, shape, and rotation of a near-Earth object important?

The size, shape, and rotation of a near-Earth object (NEO) provide vital clues about its potential impact and structure. Radar helps determine the dimensions, overall form, and rotation rate of the NEO. Knowing the size and shape aids in estimating the potential damage an impact could cause, while the rotation rate helps scientists understand its structural integrity and any complex rotational patterns. Surface features influence the reflection of radar signals. Roughness, composition, and the presence of craters are derived.

Why is it important to refine the orbital path of near-Earth objects?

Refining the orbital path of NEOs is crucial because it allows for more accurate predictions of their future trajectories. Precise radar measurements, achieved through radar technology, help scientists determine the NEO's current position and velocity. This data is then used to calculate its orbit and predict its future location. With better orbital accuracy, scientists can more reliably assess whether an NEO poses a threat of impact with Earth and plan appropriate defensive measures, if necessary.

What is planetary defense, and how does monitoring near-Earth objects contribute to it?

Planetary defense involves continuous monitoring of near-Earth objects (NEOs). Understanding their properties, and developing strategies to mitigate potential impacts. Institutions like the Institute of Applied Astronomy (IAA) and the Goldstone Complex play a critical role in this effort. By tracking NEOs, assessing their risk, and developing technologies to deflect or disrupt potentially hazardous objects, planetary defense aims to safeguard Earth from catastrophic impacts. The data collected is important to simulate possible impacts to formulate deflection strategies.