When the Rosetta spacecraft finally reaches comet 67P/Churyumov-Gerasimenko, it will become the first space mission to:
- Orbit a comet
- Attempt a landing on a comet's surface
- Follow a comet as it swings around the Sun
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The Metropolitan Police Federation, which set up the official JustGiving site, said it felt a "suitable amount" had been collected.
There is no evidence the Westminster attacker Khalid Masood was associated with so-called Islamic State or al Qaeda, the Met Police said.
Janet Ajao said in a statement: "I do not condone his actions nor support the beliefs he held that led to him committing this atrocity."