Roy Tucker is an American astronomer, who is credited with the discovery of more than 702 minor planets. Mr Tucker, who is from Jackson, Mississipi, is best known for his co-discovery of the asteroid known as Apophis 99942. The 400-metre-wide space rock continues to pose a destructive threat to Earth. Related articles NASA asteroid WARNING: 1.2KM asteroid on possible CRASH course in 2019 NASA asteroid tracker: Asteroid found TWO DAYS AGO headed for Earth However, it was a serious concern to NASA when it was first discovered in 2004, as it was thought it could strike the Earth or the moon in 2029. Mr Tucker revealed how he stumbled across the space rock during Amazon Prime’s “Asteroid Trackers” series. He said in 2008: “Apophis, that was an interesting experience. “It was just pure beginner's luck. Roy Tucker spotted Apophis in 2004 (Image: GETTY/AMAZON PRIME) Roy Tucker built the telescope in his back garden (Image: AMAZON PRIME) I saw this little moving thing and though ‘here’s a fella right here’ Roy Tucker “I saw this little moving thing and thought ‘here’s a fella right here’. “That’s when I got excited and had to tell myself to take a deep breath and slow down.” Mr Tucker went on to detail how he feared the asteroid may actually hit Earth. He added: “Then when I saw when it was going to hit – Friday the 13th – it was too much. “Suddenly I thought maybe I should stop obsessing it. Roy Tucker was worried it could strike Earth (Image: AMAZON PRIME) “But it’s a human addiction, to hunt for something and find something valuable.” Additional observations by NASA in 2006 later ruled out the possibility of an impact in 2029. However, Brian Marsden, Director at the Minor Planets Centre, revealed how the events unfolded in 2004. He said: “It became clear that it was only going to miss us by about 30,000km on April 13, 2029. “But during the next few days, the impact probability on that date went up to one in 37. Apophis still poses a threat (Image: GETTY) “That was quite surprising.” However, NASA later revealed it could pass through a gravitational keyhole and set up a future impact in 2036. By late 2008, the probability that Apophis would pass through the gravitational keyhole was determined to be very small, ruling out an impact in 2036. The threat is not completely eliminated, though. NASA did admit in 2013 there is a 150,000/1 chance of a direct impact with Earth in 2068.All rights reserved for this news site express.co.uk and under his responsibility