Space debris is becoming a much more common phenomena, with so many human assets up in space. This event was captured by our Desert Fireball Network cameras in Victoria, managed by Derek Poulton. Being able to observe these events is extremely important. We can recreate their trajectories through the atmosphere, get an idea of how and where they started to fall to Earth, and where any debris may end up on the ground. Although many events are planned for and controlled, some are not.  Networks of cameras like the DFN are the only way of monitoring large areas of sky for this purpose and potentially manage the risk for uncontrolled events.

This was a spectacular - and quite unusual - sighting over Melbourne. The duration and brightness of the event means it was witnessed and recorded by dozens of people, as far away as Bendigo. There are 2 possibilities for the origin for this fireball, either a meteor that has broken up as it hit the Earth's atmosphere, or a piece of space junk re-entering the Earths atmosphere and breaking up as it does so.

Both of these theories are possible: there was a Russian rocket launch yesterday which appears to be plausible as the source of space debris. And we have the Perseids meteor showers due to peak in a few days time. The space debris theory appears most likely at this stage - but it's a great time to get out in the night sky and look for meteors - you never know what you will see at this time of year!

The prevalence of space debris above Melbourne has unfortunately become commonplace on the sky of different places on Earth. Earth's orbital traffic has grown congested, leading to a rise in objects and subsequent close encounters. Satellite operators frequently need to take proactive steps to avoid collisions, increasing the risk of such incidents. Predicting the movement of these objects can be challenging, but it is crucial for understanding their behaviour and minimising their impact on space.

While recent events like the one in Melbourne do not directly threaten human lives, it is important to develop new satellite observation methods, like daytime monitoring, and ground-based satellite tracking sensors. Innovative approaches for detecting, identifying, and predicting the paths of groups of orbiting objects are also necessary. These efforts will greatly improve our awareness of space conditions and debris tracking, helping us better anticipate the movement of objects that could potentially harm the technology we rely on both on Earth's surface and in outer space.

Additionally, governments and private organisations worldwide need a well-defined plan for the number of objects launched, beyond showcasing capabilities, considering the consequences of limited space.

A Soyuz rocket launched from the Plesetsk cosmodrome, north of Moscow, yesterday put a GLONASS navigation satellite into orbit. The Dutch satellite watcher Marco Langbroek noted that Plesetsk had issued a warning for space debris off the coast of southern Australia.
 
The second stage of the rocket, which weighs 105 tonnes and is 25 metres long, was cast off at extremely high altitude after its fuel had been expended. Many Melburnians saw the rocket streaking across the sky as it broke into pieces, each one continuing to burn in a spectacular fireworks show. Any surviving parts of the rocket would have ended up in the sea.
 
There were also reports of a sonic boom and people felt their houses shake. Although it was moving much slower than a meteor, the rocket was still fast enough to break the sound barrier. When the US Skylab space station fell back to Earth over Western Australia in 1979, there was also a sonic boom and farmers reported animals being agitated.
 
It's not unheard of for Soyuz rocket stages to re-enter over Australia. In May 2020, an identical rocket stage from the launch of a military satellite from Plesetsk was witnessed burning up by Victorians and Tasmanians.

A piece of space junk produced a spectacular light show over Melbourne just before midnight last night. The space junk was the upper stage of a Russian Soyuz 2 rocket, which had helped launch a Glonass navigation satellite earlier on Monday.
 
As the rocket was travelling at several kilometres every second as it entered the atmosphere, it experienced vast forces that heated and broke up the rocket, producing a spectacular light show. As the rocket was at tens of kilometres altitude initially, witnesses may have underestimated the speed and altitude of the falling debris. 
 
Space junk re-entries are sometimes confused with meteors, which are also spectacular but usually far shorter events as they slam into the atmosphere at over ten kilometres per second. 
 
Video posted on social media indicates the rocket was travelling roughly south during its re-entry and away from Melbourne. As orbital rocket launches have increased over the past decade, and everyone has cameras in their phones, more and more people are seeing space junk re-entries and recognising them for what they are.
 
It is possible that small pieces of the rocket crashed to earth or into the sea, but it’s rare for space junk to damage property. Another Soyuz rocket re-entered over Melbourne back in 2014, and some pieces of the rocket were found in rural NSW sometime after.

'Space' just above the upper layers of the Earth’s atmosphere is a busy place. What we call low-Earth orbit (LEO) is the volume of space that is easiest to reach by even emerging space nations and cubesat enthusiasts alike, and so the chances of a piece of space junk falling back to Earth are increasing year on year.

Astronauts on their way to or at the International Space Station or, for that matter, those travelling to Tiangong, the Chinese Space Station, are more and more at risk of being hit by random bits of junk. Even tiny specks of paint flying at high orbital speeds could have a devastating impact and leave gaping holes in our space capsules, despite their thick metal walls.

The brightness of the object seen over Melbourne—combined with its rather subdued colours—suggests that we witnessed a pretty large chunk of abandoned satellite or the upper stage of a launch vehicle, which likely mostly burnt up on its way down to Earth. Natural meteors would more likely glow green or blue (determined by the chemical elements they're composed of), as we recently saw over Far North Queensland. We can expect to see more of such bright, man-made ‘meteors’ if we don’t find a way to deal with our unbridled ambitions in space, which will soon make the ‘Great Pacific Garbage Patch’ pale in comparison.