Woot? I've found three anomalies in the same system.
Active, not discoverable. If you find one and click the "we'll deal with this later" button, you won't find any others when you survey the rest of the system.
That doesn't seem right. I know I've found multiple anomalies in systems before, even when leaving them alone for later.
And even if I'm somehow wrong and you're describing how the game is supposed to be, it's still stupid. Finding an anomaly with a high chance of failure early in a system survey means you're screwed out of surveying the rest of the system, unless you want anomalies and are willing to risk your valuable science ship and scientist. Valuable, of course, being a relative term depending on how far into the game you are.