Sky gazers will be out on Wednesday - Prince Charles' 64th birthday as it happens - for a partial solar eclipse which will blot out up to 91 per cent of the sun.

Solar Saros 133 last gave New Zealand astronomers a treat almost two decades ago.

It will begin at 9.18am over Auckland, reaching maximum coverage at 10.28am.

The best views will be in the north with a 75 per cent eclipse in Wellington where the Prince will be.