Observation planning

Plan the observing night

The planning view combines astronomical conditions with a limited atmospheric forecast. The moon-free observing window is the part of astronomical darkness when the Moon is also below the horizon. Planetary data are shown separately for the selected calendar day.

Selected evening

The observing night

The date refers to the evening when the observing night begins. A custom date can be selected as far ahead as the current SMHI forecast covers the entire night through astronomical dawn the following morning.

Choose date

The date refers to the evening when the observing night begins.

Today's date

Calculating astronomy …

All times are local civil time at Omega Observatory.

Sun

Solar day

Rise: –:––
Set: –:––

Sun altitude −18°

Astronomical darkness

Begins: –:––
Ends: –:––

Moon

Lunar day

Rise: –:––
In the meridian: –:––
Set: –:––

Moon phase at local midnight

Moon phase

–– % illuminated

Planning summary

Moon-free observing window

––:–––––:–––– h –– min

Shows the part of astronomical darkness when the Moon is also below the horizon.

Overall weather assessment

Meteorological conditions

—

Calculated from cloud cover, precipitation probability and condensation risk.

Atmospheric forecast

Cloud cover, precipitation, temperature, humidity and condensation risk

The forecast applies to Omega Observatory for the selected evening and night and is obtained from SMHI SNOW1gv1. When astronomical darkness occurs, total cloud cover is shown from its beginning to its end, with the SMHI forecast points in between. Precipitation probability is included in the overall weather assessment.

Fetching SMHI forecast …

Total cloud coverForecast during astronomical darkness

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Temperature—Forecast range during the night

Relative humidity—Forecast range during the night

Precipitation probability—Maximum probability during the night

Minimum dew-point margin—Smaller margin means greater condensation risk

Condensation risk—Calculated from temperature and relative humidity

Sky position

Constellations suitable for observation

Shows constellations that are favourably positioned above the southern horizon during the selected moon-free observing window.

Constellation	Available	Best time	Average altitude	Direction
Calculating constellations …

Planetary data

Planets and dwarf planets

Rise, meridian passage, set, magnitude and elongation are calculated for the selected calendar day. Events after midnight are labelled with the following date.

Object	Rise	In the meridian	Set	Magnitude	Constellation	Elongation	Observing suitability
Calculating object positions …

The constellation selection is intended as planning support and is based on the practically available part of each constellation in the observatory's unobstructed southern sector during the moon-free observing window. Planetary observing suitability is a separate geometric assessment; moonlight is not included in the planetary assessment.