The asteroid TB-145 is due to come close to the Earth between 9pm GMT on the 30th October and 5 am on the day after, Halloween. Although it might seem like a horror story, it is nothing to worry about. There is no impeding crash, no need to send Bruce Willis up with a nuclear device a la Armageddon style. The asteroid will enable scientists to fix their telescopes on the rock and monitor it and of course examine it. It is possible to see it with a 6 inch apature telescope if you look in the direction of the bow Orion the hunter.
It was only recently spotted which is why so many news articles are only publishing news about it so close to the close encounter. The rock is about four hundred meters across and will pass by 302, 500 miles from the Earth which is about 1.3 times the distance between the Earth and The Moon. Once darkness falls on Halloween, the asteroid can be seen in the sky before 9 p.m. but the light from the moon should not be a problem.