Use your location, weather, darkness, horizon and targets to decide what is practical tonight and build an ordered observing plan.
Tonight turns several pieces of astronomy context into one planning workspace. It is intended to support your decision, not pretend that a single score can guarantee good observing.
Choose your planning context
Tonight uses your selected/default observing location and preferences to calculate the relevant local window. If the site or horizon changes, update the planning context before relying on target visibility.
Read the conditions
The page can bring together forecast factors, hourly conditions and astronomical darkness. Forecast data always represents a forecast from the configured provider, not a guarantee of what your sky will actually do.
Use the individual factors—cloud, wind, humidity and other available conditions—rather than relying only on the overall visual summary.
Darkness and horizon
Astronomical darkness/twilight information helps you understand when the sky reaches the level of darkness relevant to your observing or imaging plan.
Your saved horizon lets Astro Corner account for local obstructions by direction, which can explain why a technically visible target is not practical from your actual site.
Targets and projects
Tonight can use the targets and projects you have already recorded elsewhere in Astro Corner. Add useful candidates to an observing plan instead of rebuilding the same list every session.
Target information is a planning aid; always account for your equipment, sky quality, Moon, local obstructions and personal observing goals.
Run an observing plan
Open a plan to reorder items, add notes/status, remove things that no longer fit and start the session when you are ready. When you finish, complete the plan and add a reflection so tonight’s decisions are preserved with your astronomy history.
A plan is allowed to change. If weather, seeing or your own energy changes, update it rather than treating the original list as a checklist you must finish.
Planning Assistant and rig-aware recommendations
The Planning Assistant can recommend up to 10 suitable targets for a selected date, observing site and rig. You can use one of your own rigs, an eligible public rig shared by another member, or plan without a specific rig.
Recommendation cards combine object imagery/reference details with practical information such as useful dark-window duration, peak altitude/time, Moon separation and equipment/framing suitability. The ranking is astronomy-based rather than popularity-based.
Altitude graphs, darkness and skyline limits
Each recommendation can show the object’s altitude through the night together with the usable horizon/minimum-altitude line and civil, nautical and astronomical twilight/darkness periods.
Your own observing locations can use the custom horizon profile you saved. Public observing sites currently use their available/geometric horizon information unless a site-specific skyline profile is available.
Open planning in Sky Atlas
Sky Atlas is Astro Corner’s full-screen visual astronomy workspace. Open it globally from the navigation or Quick Launcher, or launch it with context from an Object, Tonight, a Target List or a Project.
The Atlas uses Aladin Lite for the interactive celestial view while Astro Corner supplies your observing locations, rigs, Tonight recommendations, target-list/project overlays and planning information.
On desktop the Atlas opens over the page you were using so Close Sky Atlas returns you to the same place. Open in new tab is available when you want the Atlas on another monitor.
When a rig has enough optical/sensor information, Astro Corner draws its calculated field-of-view footprint around the selected target. Planning markers are explicit layers and never change social-feed ranking or recommendations outside the astronomy planner.
Use Explore mode for browsing the sky and Plan mode when you want your saved site, rig, target list or Project context alongside the map.
Choose your planning context
Tonight uses your selected/default observing location and preferences to calculate the relevant local window. If the site or horizon changes, update the planning context before relying on target visibility.
Read the conditions
The page can bring together forecast factors, hourly conditions and astronomical darkness. Forecast data always represents a forecast from the configured provider, not a guarantee of what your sky will actually do.
Use the individual factors—cloud, wind, humidity and other available conditions—rather than relying only on the overall visual summary.
Darkness and horizon
Astronomical darkness/twilight information helps you understand when the sky reaches the level of darkness relevant to your observing or imaging plan.
Your saved horizon lets Astro Corner account for local obstructions by direction, which can explain why a technically visible target is not practical from your actual site.
Targets and projects
Tonight can use the targets and projects you have already recorded elsewhere in Astro Corner. Add useful candidates to an observing plan instead of rebuilding the same list every session.
Target information is a planning aid; always account for your equipment, sky quality, Moon, local obstructions and personal observing goals.
Run an observing plan
Open a plan to reorder items, add notes/status, remove things that no longer fit and start the session when you are ready. When you finish, complete the plan and add a reflection so tonight’s decisions are preserved with your astronomy history.
A plan is allowed to change. If weather, seeing or your own energy changes, update it rather than treating the original list as a checklist you must finish.
Planning Assistant and rig-aware recommendations
The Planning Assistant can recommend up to 10 suitable targets for a selected date, observing site and rig. You can use one of your own rigs, an eligible public rig shared by another member, or plan without a specific rig.
Recommendation cards combine object imagery/reference details with practical information such as useful dark-window duration, peak altitude/time, Moon separation and equipment/framing suitability. The ranking is astronomy-based rather than popularity-based.
Altitude graphs, darkness and skyline limits
Each recommendation can show the object’s altitude through the night together with the usable horizon/minimum-altitude line and civil, nautical and astronomical twilight/darkness periods.
Your own observing locations can use the custom horizon profile you saved. Public observing sites currently use their available/geometric horizon information unless a site-specific skyline profile is available.
Open planning in Sky Atlas
Sky Atlas is Astro Corner’s full-screen visual astronomy workspace. Open it globally from the navigation or Quick Launcher, or launch it with context from an Object, Tonight, a Target List or a Project.
The Atlas uses Aladin Lite for the interactive celestial view while Astro Corner supplies your observing locations, rigs, Tonight recommendations, target-list/project overlays and planning information.
On desktop the Atlas opens over the page you were using so Close Sky Atlas returns you to the same place. Open in new tab is available when you want the Atlas on another monitor.
When a rig has enough optical/sensor information, Astro Corner draws its calculated field-of-view footprint around the selected target. Planning markers are explicit layers and never change social-feed ranking or recommendations outside the astronomy planner.
Use Explore mode for browsing the sky and Plan mode when you want your saved site, rig, target list or Project context alongside the map.