May 23 (NHK) - A new star which was discovered by an amateur astronomer in Japan has kept growing brighter over two months and it can be spotted with the naked eye now.
Nakamura Yuji of the city of Kameyama in Mie Prefecture in central Japan found the star on March18.
It is in the direction of Cassiopeia. It had increased its brightness 50-fold to a star magnitude level of five by May 9.
Less than 20 new stars are found every year but most of them grow darker after growing brighter for several days.
Experts say that it is rare that a new star grows brighter for a few months and becomes bright enough to be seen without a telescope.
An expert at the National Astronomical Observatory of Japan who conducted the analysis believes that a major explosive phenomenon occurred on the surface of the star.
The observatory's Associate Professor Yamaoka Hitoshi says that it is a very rare and interesting phenomenon. He adds that he hopes that many people will be encouraged to look up to the night sky and stars.
