Let’s just let BP say this in their own words: “Currently the well remains shut-in with no oil flowing into the Gulf.”

That’s right, after 88 days and probably over 3 million barrels of oil spewed into the Gulf of Mexico, the leak begun by the explosion and sinking of the Deepwater Horizon drilling rig may finally be under control.

BP appears to have successfully attached and engaged a ‘sealing cap’ atop the broken blowout preventer, stopping the oil flow. The company is now monitoring the pressure build up in the well to check if oil is escaping anywhere, and will reopen the valves and let oil flow to its collection ship after a test period. After this – if the test is deemed a success – the well could be shut off. (The BBC has a nice graphic explaining the details, and Admiral Thad Allen’s recent press conference also lays this out.)

The relief wells currently being drilled will still be needed, but staunching the flow of oil until they can be finished is a huge triumph for BP, which has already seen its share price respond positively.

Image: the sealing cap being deployed on 11 July / BP