Siding Spring Observatory forecast › Weekend planner

Eight-week planning horizon

Choose your observing weekend

Siding Spring Observatory · ranked by total moonless dark hours across Friday and Saturday. Seasonal history is context, not the chance of clear weather on those dates.

Natural-dark sky

Site darkness stays separate from the weather and the scheduling order.

21.9–21.9 mag/arcsec²

Next seven nights in detail · Moonless calendar · Milky Way timing

Choose a planet and find its observing times →

Moonless time rank 1

6 Nov – 7 Nov

14.7h moonless / 14.7h astronomical darkness across both nights

November seasonal context
10.8 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.

Night-by-night timing & conditions

Friday

7.3h moonless · Moon 7% lit
Longest moonless stretch: 21:20–04:40

Weather not available for this night. Geometry only; recheck nearer departure.

Saturday

7.3h moonless · Moon 3% lit
Longest moonless stretch: 21:20–04:40

Weather not available for this night. Geometry only; recheck nearer departure.

Moonless time rank 2

4 Dec – 5 Dec

11.3h moonless / 13.3h astronomical darkness across both nights

December seasonal context
13.2 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.

Night-by-night timing & conditions

Friday

5.3h moonless · Moon 18% lit
Longest moonless stretch: 21:40–03:00

Weather not available for this night. Geometry only; recheck nearer departure.

Saturday

6.0h moonless · Moon 11% lit
Longest moonless stretch: 21:40–03:40

Weather not available for this night. Geometry only; recheck nearer departure.

Moonless time rank 3

13 Nov – 14 Nov

9.3h moonless / 14.7h astronomical darkness across both nights

November seasonal context
10.8 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.

Night-by-night timing & conditions

Friday

5.0h moonless · Moon 17% lit
Longest moonless stretch: 23:40–04:40

Weather not available for this night. Geometry only; recheck nearer departure.

Saturday

4.3h moonless · Moon 24% lit
Longest moonless stretch: 00:20–04:40

Weather not available for this night. Geometry only; recheck nearer departure.

Moonless time rank 4

16 Oct – 17 Oct

7.3h moonless / 16.3h astronomical darkness across both nights

October seasonal context
14.9 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.

Night-by-night timing & conditions

Friday

4.0h moonless · Moon 31% lit
Longest moonless stretch: 01:00–05:00

Forecast cloud range: 96–96% at 1 available dark-time samples. Not full-night coverage or a probability.

Saturday

3.3h moonless · Moon 40% lit
Longest moonless stretch: 01:40–05:00

Forecast cloud range: 12–12% at 1 available dark-time samples. Not full-night coverage or a probability.

Moonless time rank 5

30 Oct – 31 Oct

7.0h moonless / 16.0h astronomical darkness across both nights

October seasonal context
14.9 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.

Night-by-night timing & conditions

Friday

3.0h moonless · Moon 77% lit
Longest moonless stretch: 21:00–00:00

Weather not available for this night. Geometry only; recheck nearer departure.

Saturday

4.0h moonless · Moon 66% lit
Longest moonless stretch: 21:00–01:00

Weather not available for this night. Geometry only; recheck nearer departure.

Moonless time rank 6

27 Nov – 28 Nov

3.3h moonless / 13.3h astronomical darkness across both nights

November seasonal context
10.8 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.

Night-by-night timing & conditions

Friday

1.3h moonless · Moon 89% lit
Longest moonless stretch: 21:40–23:00

Weather not available for this night. Geometry only; recheck nearer departure.

Saturday

2.0h moonless · Moon 80% lit
Longest moonless stretch: 21:40–23:40

Weather not available for this night. Geometry only; recheck nearer departure.

Moonless time rank 7

20 Nov – 21 Nov

2.0h moonless / 14.7h astronomical darkness across both nights

November seasonal context
10.8 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.

Night-by-night timing & conditions

Friday

1.3h moonless · Moon 80% lit
Longest moonless stretch: 03:20–04:40

Weather not available for this night. Geometry only; recheck nearer departure.

Saturday

0.7h moonless · Moon 88% lit
Longest moonless stretch: 04:00–04:40

Weather not available for this night. Geometry only; recheck nearer departure.

No moonless darkness

23 Oct – 24 Oct

0.0h moonless / 16.0h astronomical darkness across both nights

October seasonal context
14.9 usable nights/month on average · 2005–2024. Historical regional cloud and darkness, not this weekend’s weather odds.

Night-by-night timing & conditions

Friday

0.0h moonless · Moon 92% lit
No moonless dark window

Weather not available for this night. Geometry only; recheck nearer departure.

Saturday

0.0h moonless · Moon 96% lit
No moonless dark window

Weather not available for this night. Geometry only; recheck nearer departure.

How to use this planner

Choose a weekend with enough moonless time, then check the weather and target outlook before travelling. Times use Australia/Sydney and approximately 20-minute geometry samples. Friday and Saturday are ranked together; hours need not form one continuous window.

The regional NASA climate baseline counts nights with at least three hours of astronomical darkness and mean nighttime cloud at or below 30%. It does not measure telescope seeing or guarantee clear skies. No weather probabilities are inferred from monthly averages. Longer-lead forecasts have coarser sampling.

Full seasonal history and definitions →