Missions
Launch Windows, Holds, and Scrubs Explained
Read a launch listing and follow a countdown without confusing a scheduled target time with a guaranteed liftoff.
Prepared with AI assistance using the primary sources linked below. How Astroboat works
A launch has to meet its destination
A launch window is a period in which a vehicle can depart and still satisfy mission requirements. The target orbit, destination geometry, vehicle performance, and operational constraints influence that opportunity. Some windows are brief; others allow a range of possible liftoff times.
An interplanetary opportunity also depends on where Earth and the destination are in their orbits. Missing one day's attempt is not always equivalent to missing an entire planetary departure opportunity, so read which kind of window a source is discussing.
Pauses are part of launch operations
A hold pauses the countdown. Some holds are planned into the procedure; others give teams time to investigate an issue. The clock can be recycled to an earlier point. A countdown display is therefore not always a simple wall-clock promise of liftoff.
A scrub ends a particular launch attempt. It does not mean the entire mission is canceled. Weather, hardware checks, range safety, and other conditions can require another attempt, and a new date may remain unconfirmed while teams assess the situation.
Read the status alongside the time
In Astroboat's Events list, check the event date, time-zone label, and status together. A no-earlier-than time is a planning target. A launch success also needs context: liftoff, orbital insertion, and payload deployment are different milestones.
Open the source link before making travel plans or joining a livestream. Cached listings may lag a late change. Save both the UTC time and your converted local date, then use the provider's live updates for the final countdown and outcome.