A SpaceX fanatic created a website to find out when Starlink satellites were visible in his location. After 5 days, it went viral. You can use the site to see what where to look and how long for.

More people across the world are reporting sightings of SpaceX's Starlink satellites, which tend to resemble a chain of fairy lights zooming across the night sky.

This is no surprise considering the rate at which SpaceX are launching satellites into orbit via its Falcon 9 rocket. The company have blasted off 16 Falcon 9 rockets this year with a maximum of 60 satellites per launch.

Elon Musk's space firm has currently more than 1,500 satellites in orbit and aims to get up to 42,000 up there by mid-2027.

Most recently, Starlink satellites have been spotted over the UK, Ireland, and cities in the US, including Arizona, California, and Los Angeles.

For those who are interested in spotting Starlink satellites, Find Starlink can give you a good idea of when SpaceX's spacecraft will be visible in your location.

Users can choose from a multitude of cities across the world to check out when and where to look for Starlink satellites.

The creator of Find Starlink, who prefers to remain anonymous online, told Insider he launched the website two years ago for himself, his brother, and a friend living in different parts of the world.

"Find Starlink was created three days after the first Starlink launch (24 May, 2019) because I wanted to see the Starlink train and none of the existing websites tracked Starlink at that point," said the creator.

"I saw some unbelievable images of the Starlink train from the first Starlink launch, and wanted to see it with my own eyes," he added.

The website, which he made in one evening, got half a million requests within its first five days of launching, the creator said.

He has received emails from people who helped build on Apollo rockets and those who have requested ruling out UFO sightings, he said.

Once you have typed in your location, the site will show timings with good, average, and poor visibility around that area. It tells you which direction to look in, how long the satellites will be noticeable for, and the elevation.

Find Starlink warns users that the timings are not 100% accurate as the orbit of the satellites can change.

"I prefer to keep user expectations and hype low, so I'd say 'try it at your own risk,' and 'don't blame me if you waited outside in the cold and saw nothing,'" the creator said.

The website is accurate four to five days after SpaceX launch a new batch of Starlink satellites, he said, adding that he receives a lot of emails about successful sightings on a daily basis.

One week after the launch, it's tricky to predict where the satellites will be because they are assigned to their level orbit where they are less reflective and more difficult to see from the ground, the creator said.

This is called "rolling behaviour," when SpaceX reduce the brightness of the satellites between 300 km to 550 km altitude to not disturb astronomers, he said.

If your area isn't listed, you can type in the longitude and latitude of the location to check when Starlink satellites will zoom overhead.

So, how does it work?

After collecting some calculations off the Reddit SpaceX community, the creator said he put a simple program together to predict timings of the Starlink satellites. From this, he made Find Starlink.

The website tracks the "leader" of each Starlink satellite train and predicts its path as all the other satellites will follow behind.

Every minute of the first five days after the launch, the site calculates a triangle between the Sun, the satellite and the location to calculate how good the visibility is going to be in that area, the creator said.

The website then ranks the predicted visibility into "good", "average" and "poor" based on the calculations.

Astronomers have become increasingly frustrated with Starlink satellites as their bright lights jeopardize astronomical research by obscuring the stars and leaving bright streaks across their images.

In response, SpaceX added darkening sun visors to its Starlink internet satellites, making them almost invisible to the naked eye.

This means it's harder for Find Starlink to track the satellites.

A few weeks after a SpaceX launch when the satellites are assigned in orbit, a pop-up may show on the website saying that Starlink satellites aren't visible at the moment as SpaceX has "reduced [the satellites'] brightness to avoid disturbing astronomers."

But once SpaceX blasts another batch of satellites into orbit, Find Starlink says they'll be much easier to spot in the first three to four days.