SIR – Did your correspondent D Rhodes write his letter about the meteor over Russia before the latest information from NASA?

Five minutes on the internet on Saturday established that the meteor probably had a mass of 10,000 tonnes, and a diameter around 15m (50ft) – too small to have been detected although it could have been tracked once located. Also, there are around 100,000 such objects in space with the potential of striking earth.

In contrast, 2012 DA14 had a diameter around 45m (150ft).

Another snippet was that a rather crazy Russian politician had said it was not a meteor but instead a US secret weapons trial (despite Russian scientists having recovered fragments of the meteor).

Perhaps D Rhodes can also say what he would have done if he had known about it. As amply demonstrated in many Hollywood disaster movies, evacuating a major city at a few hours’ notice is not practicable.

Ron Harding, Beck Houses, Bingley