Chile · 24.63°S 70.40°W · 2400 m
Stargazing in Atacama Desert
The driest desert on Earth. Some sites average over 300 clear nights a year.
- Sky quality
- Bortle 1 — pristine
- Clear nights a year
- ≈ 298
- Best month overall
- March
- Milky Way core
- February–October
The Milky Way shows structure and casts a faint shadow; the zodiacal light and airglow are visible to the naked eye.
Key facts
- Sky quality
- Bortle 1 — pristineBortle class 1
- Average clear nights
- 298 per yearNights averaging under 30% cloud, 10-year ERA5 record
- Best Milky Way season
- February–OctoberPeak month: March, core reaching 67°
- Darkness quality
- Excellent10.5 h of astronomical darkness at its darkest, in May
- Typical cloud cover in July
- 20%71% of nights come in under 30% cloud
- Best month for astrophotography
- OctoberAbout 20.1 dark, moon-free, statistically clear nights
- Coordinates
- -24.6272, -70.40422400 m elevation · America/Santiago
Questions answered on this page
- Is tonight good for stargazing in Atacama Desert?
- Is the Milky Way visible from Atacama Desert?
- How many clear nights does Atacama Desert get each year?
- What is the best month for astrophotography in Atacama Desert?
- How many hours of true darkness does Atacama Desert get each month?
- How dark is the sky in Atacama Desert on the Bortle scale?
- When is the Milky Way core above the horizon from Atacama Desert?
- Should I drive somewhere darker than Atacama Desert?
The Atacama is why the world's largest telescopes are in northern Chile. A cold offshore current, the Andes rain shadow and permanent subtropical high pressure combine into a place where cloud is the exception; Paranal and the surrounding plateau record photometric conditions on the majority of nights.
For a visiting observer the southern sky is the real prize: the Magellanic Clouds, Eta Carinae, Omega Centauri and a galactic core that passes near the zenith in June and July. San Pedro de Atacama is the usual base, though its own lights are growing — an hour out into the desert is still perfectly black.
Evergreen intelligence
The four questions people ask about Atacama Desert
Computed from 10 years of ERA5 reanalysis at these coordinates and a full year of Sun and Moon geometry — not copied from anywhere.
- How many clear nights does Atacama Desert have?
- About 298 nights a year average less than 30% cloud cover, based on 10 years of ERA5 daily reanalysis at -24.63, -70.40. The clearest month is March at 91% of nights; when you also require darkness and no Moon, roughly 212 nights a year are genuinely usable for faint targets.
- What is the best month for the Milky Way in Atacama Desert?
- March. The galactic centre clears 10° from February to October, and in March it reaches 67° while the sky is astronomically dark, with about 4.5 hours of usable core time a night and 91% of nights averaging under 30% cloud.
- When is it darkest in Atacama Desert?
- May gives the most true darkness — an average of 10.5 hours a night with the Sun more than 18° below the horizon.
- When should I plan an astrophotography trip to Atacama Desert?
- October offers the most nights that are simultaneously dark, moon-free and statistically clear — about 20.1 of them. Book around the new Moon in that month and keep two spare nights; a single fixed date at any location is a coin toss.
Darkness calendar
Atacama Desert month by month
Astronomical darkness and Moon geometry are computed for these coordinates. Cloud figures are ten-year ERA5 daily means. Rating combines darkness, moon-free nights and clear-sky odds.
| Month | Astro darkness | Moon-free dark nights | Avg cloud | Clear nights | Milky Way core | Rating |
|---|---|---|---|---|---|---|
| Jan | 7.7 h | 22 | 16% | 78% | — | Excellent |
| Feb | 8.3 h | 21 | 19% | 77% | 36° max | Excellent |
| Mar | 9.2 h | 20 | 7% | 91% | 67° max | Excellent |
| Apr | 9.8 h | 20 | 12% | 83% | 85° max | Excellent |
| May | 10.5 h | 21 | 22% | 69% | 85° max | Excellent |
| Jun | 10.5 h | 21 | 23% | 71% | 85° max | Excellent |
| Jul | 10.5 h | 21 | 20% | 71% | 85° max | Excellent |
| Aug | 10.0 h | 22 | 8% | 90% | 85° max | Excellent |
| Sep | 9.4 h | 22 | 8% | 91% | 72° max | Excellent |
| Oct | 8.7 h | 22 | 7% | 91% | 46° max | Excellent |
| Nov | 7.9 h | 23 | 9% | 87% | — | Excellent |
| Dec | 7.5 h | 24 | 14% | 81% | — | Excellent |
"Moon-free dark nights" counts nights with at least two hours of astronomical darkness during which the Moon stays below the horizon. "Clear nights" is the share of days in the ERA5 record averaging under 30% cloud cover.
Practical
What Atacama Desert is actually good for
- Southern-sky deep sky
- Magellanic Clouds
- Milky Way core near the zenith
- Near-guaranteed clear nights
For a decision on a specific night rather than a season, the SnapCosmos Night Engine scores tonight and the next six nights from these coordinates — . The method, weighting and known limits are documented on the Night Engine page, and its measured accuracy is published here.
FAQ
Common questions about the sky in Atacama Desert
- Can you see the Milky Way in Atacama Desert?
- Yes. Atacama Desert sits at Bortle 1 — pristine, where the Milky Way is an obvious, structured band whenever the galactic centre is above the horizon and the Moon is down.
- When is the best time of year to stargaze in Atacama Desert?
- It depends on what you want to see, and the month-by-month table on this page ranks every month by hours of astronomical darkness, moon-free nights and ten years of cloud statistics for these exact coordinates.
- How dark does it get in Atacama Desert?
- Atacama Desert is at latitude 24.6°S, and this page computes the hours of true astronomical darkness — Sun more than 18° below the horizon — for every month of the year at that latitude.
- Is tonight a good night in Atacama Desert?
- The SnapCosmos Night Engine scores tonight for these coordinates against the coming week using live cloud forecasts, Moon geometry and darkness, and returns a single go, wait or skip recommendation.
Where these numbers come from
- Ten-year cloud-cover climatology and historical night rankingERA5 reanalysisECMWF / Copernicus Climate Change Service
- Hourly cloud cover, precipitation, humidity and visibility forecastsOpen-Meteo forecast and archive APIOpen-Meteo
- Sun, Moon and planet positions, rise and set times, twilight phasesAstronomy Engine (VSOP87 / ELP2000 series)Don Cross, after the IMCCE and JPL analytical theories
- Bortle class and sky-brightness context for each locationWorld Atlas of Artificial Night Sky Brightness (Falchi et al., 2016)Science Advances / Light Pollution Map
- Definitions of civil, nautical and astronomical twilight, and lunar phase conventionsAstronomical Applications DepartmentUnited States Naval Observatory
Figures on this page last recomputed .
Related