The observability layer
Tonight, from your sky
The surveys watch everything; this page answers the only question that matters at the eyepiece — can I see it tonight? Your location and gear stay in your browser; nothing is sent to us.
Where and with what?
Don't check — get paged
When something crosses into reach of your setup from your sky, we email you — with days of runway, not after the peak. At most 3 alerts a week, one per object ever, plus a Monday digest that's honest about quiet weeks.
Nothing within reach tonight — and that's a real answer
Verdicts compare the most recent survey magnitude (its filter is shown in data mode) against an estimated limit for your gear and sky. Brightness changes nightly and estimates are estimates — treat "borderline" as an invitation, not a promise. Objects with no photometry in 3+ days are held back as stale rather than shown with implied brightness.