Rocket Lab CEO with the Electron rocket
Rocket Lab CEO Peter Beck stands next to a Electron rocket, the type of rocket the company launched into orbit on January 21. Rocket Lab

There's no room for symbolism in space, according to astronomers.

After a US space company launched a giant disco ball into space on 21 January, astronomers are voicing their anger.

Rocket Lab launched a rocket carrying two small satellites from its private launch pad in New Zealand. Its founder and chief executive Peter Beck said it was an "almost unprecedented" step in commercial space exploration.

However, it quickly was made public that in addition to the satellites, the company also launched a giant disco-ball almost a meter wide (91cm), called the Humanity Star, into space. The ball is made from carbon fibre and fitted with 65 reflective panels.

Rocket Lab said in a statement that the star will produce a reflection of the Sun's rays. This will in turn create a flashlight that will be visible from any point on Earth, and is expected to be the brightest point seen at night for the next 9 months, before it re-enters our atmosphere.

The company said it wanted the Humanity Star to remind people about how fragile Earth is within the universe, with Beck adding that it will "create a shared experience for everyone on the planet".

But Rocket Lab seems to have missed the mark. The Guardian reports that several astronomers have come forward to criticise the move, saying it will disrupt space's balance.

Light pollution, which how visible the Milky Way is from Earth, is spreading, meaning 60% of the Milky Way can't be seen from certain points on Earth.

Some experts fear a huge disco ball dangling from a satellite will not help curb the scarring trend.

"This one instance won't be a big deal but the idea of it becoming commonplace, especially at larger scales, would bring astronomers out into the street," said Richard Easther, head of the University of Auckland's Physics department.

"I can understand the exuberance for this sort of thing but I also get the sense that they did not realise that people could see a downside to it," he added.

Astronomer Ian Griffin told the New Zealand Herald that Rocket Lab and Peter Beck had "vandalised the night", while another expert called it "bright long-term space graffiti".

Griffin said the first act of New Zealand as a space-faring nation was to pollute the universe for everyone, and that people should enjoy seeing the night sky and Milky Way while they still can, because it won't last.

Writing in the Scientific American, the director of Columbia University's Astrobiology department, Caleb Scharf, called the ball "abusive".

"Most of us would not think it cute if I stuck a big flashing strobe-light on a polar bear, or emblazoned my company slogan across the perilous upper reaches of Everest," he wrote.

"Jamming a brilliantly glinting sphere into the heavens feels similarly abusive. It's definitely a reminder of our fragile place in the universe, because it's infesting the very thing that we urgently need to cherish."