Scientists slam ‘indefensible’ axing of Nasa’s $450m Viper moon rover

Viper – which stands for volatiles investigating polar exploration rover – during its test phase. Photograph: Bridget Caswell/GRC/Nasa

Thousands of scientists have protested to the US Congress over the “unprecedented and indefensible” decision by Nasa to cancel its Viper lunar rover mission.

In an open letter to Capitol Hill, they have denounced the move, which was revealed last month, and heavily criticised the space agency over a decision that has shocked astronomers and astrophysicists across the globe.