Observation planning

Plan the observing night

The planning view applies to observing conditions at Omega Observatory and combines astronomical calculations for the observatory's geographic location with a local meteorological 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

Show star chart

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.

Meteorological forecast

Observing conditions

Quick overview first, the night’s development next, and exact values below.

Fetching forecast …

Fetching data from SMHI, 7Timer ASTRO and LFV …

Deep-sky

—Calculated for the selected night.

High magnification

—Calculated for the selected night.

Operational risks

—Condensation risk and surface wind for the selected night.

Best observing period

—Shown only when the minimum requirements for a recommended period are met.

Night profile

Conditions during astronomical darkness

Seeing and transparency use the nearest 7Timer forecast point. Surface wind uses the nearest SMHI forecast point at 10 m; critical sector 178°–237°.

Temperature

— —

Relative humidity

— —

Precipitation probability

—

Maximum probability during the night.

Minimum dew-point margin

—

0°8°+

A lower value means greater condensation risk.

Condensation risk

—

Calculated from temperature and relative humidity.

Jet stream

—

Wind bands at 8–10 km altitude.

Seeing

—

Atmospheric image stability.

Transparency

—

Atmospheric transparency.

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 …

Astronomical times and sky positions are calculated for Omega Observatory's geographic location. Visibility of the starry sky is determined to a large extent by the observatory's latitude, approximately 58° N. 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.