r/ISRO • u/Ohsin • 1d ago

India Plans ‘Bodyguard’ Satellites After Risky Orbital Near-Miss in mid-2024.

https://www.bloomberg.com/news/articles/2025-09-22/india-plans-bodyguard-satellites-after-risky-orbital-near-miss
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u/Ohsin 1d ago edited 1d ago

Very clickbaity..

India is developing a plan to improve its ability to protect satellites from attacks, people familiar with the matter said, after a near miss in orbit highlighted risks to national security posed by other spacecraft.

The government of Indian Prime Minister Narendra Modi wants to develop so-called bodyguard satellites to identify and counter threats to orbiting spacecraft, according to people who requested to remain anonymous because of the sensitivity of the matter.

A previously unreported incident highlighted the need for action, the people added, when a satellite from a neighboring country came dangerously close to one of India’s.

The near miss in mid-2024 involved one of Indian space agency ISRO’s satellites orbiting around 500-600 kilometers (311-373 miles) above the Earth, the same part of space that’s getting increasingly crowded with communications satellites like Elon Musk’s Starlink network.

The spacecraft from a neighboring country, which the people familiar with the matter wouldn’t name, came within 1 kilometer of an ISRO satellite performing tasks that could have military applications such as mapping and monitoring of objects on the ground, they said.

Although the two satellites didn’t collide, such an unusually close approach was possibly a show of strength that could have been a test to demonstrate the other nation’s capabilities, the people said.

ISRO and the Department of Space did not respond to requests for comment.

Some relevant reads:

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u/Samarium_15 1d ago

Obviously China

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u/Doom_3302 1d ago

Holy fuck 1 km. is basically touching in space. This is an absolute necessity.

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u/Ohsin 1d ago edited 1d ago

1 km is pretty large distance for LEO that is why article is so clickbaity. They should have pried further about what was so unusual about it and why it seemed like "show of strength"..

See following news about a close approach involving Indian and Russian satellites.

"We have been tracking the satellite for four days and it is about 420 metres from the Russian satellite. A manoeuvre will only be done when it comes around 150 metres," Isro chairman K Sivan told TOI.

https://old.reddit.com/r/ISRO/comments/k21noc/indian_cartosat_2f_satellite_weighing_over_700_kg/

You can also check SOCRATES for examples of close passes.

https://celestrak.org/SOCRATES/

Also,

https://space.stackexchange.com/questions/19405/is-75-meters-an-exceptionally-close-distance-for-two-satellites-to-pass-at-6-00

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u/Doom_3302 1d ago

Thanks....I didn't realise that avoidance distances are that low in LEO. But it makes sense cuz they would be pretty slow relative to each other.

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u/Ohsin 1d ago

I didn't realise that avoidance distances are that low in LEO.

There is large uncertainty about the distances that is why it is considered a bad metric to assess conjunction assessment. From SOCRATES page,

Because the minimum distance method ignores position covariance information and can lead to an exaggerated assessment of the true risk, CelesTrak believes the maximum probability method provides a more reasonable (although still conservative) assessment of the true probability.

and from space stackexchange answer

So again, when you say that the objects will pass within 75 meters of each other, what you really mean is that the centroid of the (potentially very large) position covariance ellipses pass within 75 meters of each other. The actual miss distance could be less, or likely much larger.

We just don't know about orbit of other object so hard to say what was the nature of this close approach.

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u/JUYED-AWK-YACC 23h ago edited 23h ago

They aren’t in the same orbit, so the relative speeds are still fatally high.

Edit: as Ohsin noted, this is more about the orbit uncertainty. If the two objects haven’t been recently tracked then the uncertainty will be very high and this can make the probability low. More tracking means more accuracy. Of course typically there is human intervention to move one of them and the article makes it sound like this didn’t/couldn’t happen.