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?
The visual-limit estimate is just a starting point — correct it if you know better; you're more accurate than our formula.
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.