By Christine McGourty
BBC science correspondent
A new project known as Galaxy Zoo is calling on members of the public to log on to its website and help classify one million galaxies.
The classic spiral: M51, also known as the whirlpool galaxy
The hope is that about 30,000 people might take part in a project that could help reveal whether our existing models of the Universe are correct.
Computer users undergo a three-minute online tutorial and are then allocated a series of images and asked to decide whether each one shows a spiral or an elliptical galaxy.
If it's a spiral galaxy, they're asked to decide which way it appears to be rotating.
The images come from the Sloan Digital Sky Survey telescope in New Mexico, US.
Kevin Schawinski, an astrophysicist at Oxford University, UK, is one of the team who devised the project.
"I classified about 50,000 galaxies myself in a week," he said. "It was mind-numbing."
He's hoping that involving the public will speed the work up.
"It's not just for fun," he added. "The human brain is actually better than a computer at pattern recognition tasks like this. Whether you spend five minutes, 15 minutes or five hours using the site, your contribution will be invaluable."
The project was inspired by others, such as stardust@home, in which the US space agency invited the public to help sort through dust grains obtained by a mission to a comet.
Dr Chris Lintott, another member of the Oxford team, said: "What the Stardust team achieved was incredible, but our galaxies are much more interesting to look at than their dust grains.
"We hope that participants in Galaxy Zoo will not only contribute to science, but have a lot of fun along the way."
He added: "One advantage is that you get to see parts of space that have never been seen before. These images were taken by a robotic telescope and processed automatically, so the odds are that when you log on, that first galaxy you see will be one that no human has seen before.
"It's not often you get to see something unique."
The hope is to have 20,000-30,000 people take part and to have some results in a matter of months.
Cosmologist Kate Land, another member of the team, is expecting amateurs to make a better job of it than the experts: "We get hung up on the details. I got stuck myself! I've found that members of public are much better; they just go with it, on first instinct.
"They don't get too stressed about the images. Astronomers aren't the best people to do this."
She is hoping to test theories about the rotation of galaxies.
She added: "Some people have argued that galaxies are rotating all in agreement with each other, not randomly as we'd expect.
"We want people to classify the galaxies according to which way they're rotating and I'll be able to go and see if there's anything bizarre going on. If there are any patterns that we're not expecting, it could really turn up some surprises."