Meteors & Comets

What it does

Shows which of the 12 major annual meteor showers are active on a date and whether each one's radiant is visible from your location, and lists upcoming comet apparitions with their expected peak brightness.

What you need

• For meteor showers, a location is optional. Without one, the lists still show each shower's peak date and rate, but not tonight's visibility. Set it with the Location picker.
• For comets, no location.
• No network. The shower and comet data is built into the app, so the tool works offline.

How to use it

1. In Object Type, choose Meteor Showers or Comets.
2. Meteor Showers: set your location with the picker at the top, then pick a date in the Date card. Use the step buttons to move by days, weeks, or months, and Today to return to today.
3. Read the Showers card. It lists all 12 major showers sorted by peak date, with showers active on your chosen date at the top.
4. Comets: read the Upcoming Comets card. It lists every comet in the app's data whose closest approach to the Sun has not yet passed, soonest first.

Reading the results

• Showers: each row shows the shower name, its ZHR (zenithal hourly rate, the most meteors you could expect per hour under ideal dark skies), and its peak date. For a shower active on your chosen date and with a location set, the row also shows the time window when the radiant is up and the Moon is not in the way, plus the Moon's illumination. Other showers show their active dates, peak, ZHR, and parent body.
• Eye icon on an active shower row: an open eye means a clear viewing window of two hours or more, an eye with a minus sign means a shorter window, and a crossed-out eye means not visible tonight. With no location, there is no icon.
• "Radiant not visible tonight" or "No clear window": the radiant never rises, or moonlight or daylight leaves no usable time.
• Comet rows: the comet's designation and name, its Perihelion date (closest to the Sun, usually near its brightest), est. mag (expected peak brightness as an apparent magnitude, where lower is brighter), the orbit (years for periodic comets, or "long-period"), and a short viewing note.

Live Activity countdown

On the Showers view, the Live Activity card counts down to tonight's best meteor shower window. The app picks the active shower with the highest rate that has a clear window. Under Count down to, choose Start, End, or Both. If no shower has a clear window tonight, the card says so. It is part of Pro and only on iPhone. Tap Start countdown to put it on your Lock Screen, and in the Dynamic Island on iPhones that have one. On the Free plan the button reads Start countdown (Pro) and opens the upgrade screen. Tap Stop countdown to end it. Changing a choice while it runs restarts it with the new choice. It only starts when you tap Start with the app open, replaces any other countdown that is running, and iOS ends it after about 8 hours. Settings, Notifications, Live Activities shows what is running and lets you stop it.

Tips

• On iPhone, with a location set, showers that are active tonight and whose radiant rises tonight show a › on their row. This follows tonight, whatever date you are browsing. Tap the row to open a compass that shows your live heading and tells you which way to turn to face the radiant. While you face it, the row's border lights up. If the radiant is down right now, it says it is below the horizon. Tap the row again to close it. It is not shown on web.
• Predicted comet magnitudes are estimates. Comets can fizzle below forecast or outburst above it.
• The comet list does not compute whether a comet is visible from your location, so check sky conditions and position separately.
• A bright Moon washes out fainter meteors. Compare the Moon illumination shown on each row.
• Shoot Forecast shows active showers and the next comet together on its Meteors & Comets card.
• The old Comet Tracker address opens this tool's Comets view.