Milky Way Season Near the Equator: Month by Month from Guyana

Milky Way Season Near the Equator: Month by Month from Guyana

From Guyana the Milky Way core is up in a dark sky from February to October: before dawn early in the year, all night in June, and in the evening from July.

Milky Way Season Planner · How to See the Milky Way · Dark Sky Window

All times on this page are Guyana time (America/Guyana, UTC-4, no daylight saving). Georgetown stands for the coast and Lethem for the interior savannah. How the numbers were made is explained at the end of the page.

The short answer

• Season: February to October. The core is too close to the Sun from November to January.
• Best months: May, June and July, with 7 to 8.5 hours a night of core in true darkness.
• Time of night: before dawn from February to May, most of the night in June, in the evening from July to October.
• Height: the core crosses the sky due south and peaks about 54° up from Georgetown and about 58° up from Lethem.
• The catch: the best months fall in the main wet season on the coast (mid-April to the end of July). The dry-season chances are the evenings of August to October and the pre-dawn hours of February and March.
• The Moon: on an average night the Moon is up for about half of the core hours. Plan around the two weeks centred on new Moon.

The year as a wheel: each month's night from 18:00 to 06:00, the core's window in it, and the wet season around the rim, for Georgetown or Lethem.

Month by month: the sky

"Core hours" counts the time when the Sun is more than 18° below the horizon (astronomical darkness) and the galactic core is at least 15° above the horizon. Fifteen degrees is the minimum the Milky Way Season Planner uses for wide-field photos, because anything lower sinks into haze and trees. The Moon is ignored in this table; it has its own section below.

| Month | Georgetown: core hours per night | Before midnight | After midnight | Lethem: core hours per night | Core window on the 15th (Georgetown) | |---|---|---|---|---|---| | January | 0.1 | 0.0 | 0.1 | 0.1 | none | | February | 1.6 | 0.0 | 1.6 | 1.7 | 03:25 to 05:00 | | March | 3.4 | 0.0 | 3.4 | 3.5 | 01:30 to 04:50 | | April | 5.1 | 0.6 | 4.5 | 5.3 | 23:30 to 04:35 | | May | 7.0 | 2.5 | 4.4 | 7.2 | 21:35 to 04:25 | | June | 8.5 | 4.3 | 4.3 | 8.7 | 19:30 to 04:25 | | July | 7.1 | 4.5 | 2.6 | 7.4 | 19:30 to 02:40 | | August | 5.2 | 4.6 | 0.6 | 5.4 | 19:20 to 00:40 | | September | 3.5 | 3.5 | 0.0 | 3.7 | 19:05 to 22:35 | | October | 1.7 | 1.7 | 0.0 | 1.9 | 18:50 to 20:40 | | November | 0.2 | 0.2 | 0.0 | 0.2 | none | | December | 0.0 | 0.0 | 0.0 | 0.0 | none |

Read the table like this:

• In February and March the core rises after midnight and is only well up in the last hours before dawn. Set an alarm.
• In April and May it rises in the late evening and is best after midnight.
• In June it rises around sunset and stays up all night, peaking due south around midnight.
• From July to October it is already up at dusk, highest in the evening, and sets earlier each month.
• By mid-October only about the first 2 hours after dark remain, and during November the last of it sinks into twilight.

In which months is the core a before-dawn target rather than an evening one?

• February to May (the right answer)
• July to October
• November to January
• June only

In February and March the core rises after midnight and is only well up before dawn; in April and May it rises in the late evening and is best after midnight.

Each night the core rises about 4 minutes earlier, so its window moves about 2 hours earlier each month. Lethem, closer to the equator, gets a few more minutes of core each night than Georgetown and sees it about 3° higher.

The table as a chart: hours of core in true darkness, month by month, from Georgetown and Lethem.

The season night by night at 22:00: before dawn in February to April, all night May to July, evenings only August to October.

Why the core has a season at all

The galactic core lies in Sagittarius, in the direction the Sun passes through in late December (closest around 19 December). So in December and January the core is up during the day and hidden in sunlight. As Earth moves around its orbit, the Sun moves away from Sagittarius and the core appears first before dawn, then earlier each night, until by October it sets soon after dark.

Why is there no core season from November to January?

• The core is below the horizon all year at that time
• The Sun passes close to Sagittarius, so the core is up in daylight (the right answer)
• The rainy season hides it
• The Moon is always full then

The galactic core lies in Sagittarius, the direction the Sun passes through in late December, so in December and January the core is up during the day and hidden in sunlight.

Why the equator is a good place to see it

• It climbs higher than in the north. From Georgetown the core peaks about 54° above the southern horizon, and about 58° from Lethem. From 40° N it never gets above about 21°. Only observers near 29° S (southern Brazil, South Africa, Australia) see it pass straight overhead.
• The nights are longer in core season. Near the equator night lasts close to 12 hours all year and twilight is short, about 70 to 77 minutes from sunset to full darkness at Georgetown. In June Georgetown averages about 9 hours of astronomical darkness a night, against about 5 hours at 40° N, and none at 50° N, where the June sky never gets fully dark.
• So you get more core time. A June night gives about 8.5 hours of core at 15° or higher from Georgetown, against about 4 hours from 40° N.

Many "Milky Way season" guides are written for 35° to 50° N. At 40° N the core clears 15° only from about March to September, for at most about 4 hours a night in June, and from 50° N it never reaches 15° at all. From Guyana the season is longer, and it starts before dawn.

The Moon

A bright Moon washes out the faint dust lanes that make the core worth seeing. Averaged over 2026 to 2028, the Moon is above the horizon for about half of all core hours in every month of the season. Which half depends on the time of night the core is up:

• Pre-dawn months (February to May): the core is moonless from about 3 or 4 days before new Moon until around first quarter, and partly moonless until about 10 days after new Moon. A waning Moon rises in the small hours and spoils the pre-dawn sky.
• Evening months (July to October): the core is moonless from around last quarter until about 3 or 4 days after new Moon. A waxing Moon sits in the evening sky and spoils it.
• June: the core is up all night, so the nights closest to new Moon are best.

One night with the core, the Moon and twilight together: compare a new-Moon night with a full-Moon night.

Nights per month with at least 2 hours of moonless core from Georgetown (average of 2026 to 2028):

| Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | |---|---|---|---|---|---|---|---|---| | 4 | 14 | 17 | 19 | 21 | 19 | 16 | 14 | 6 |

Every night of the coming season, coloured by its hours of moonless core, with the nights of 2 hours or more counted for each month.

For a chosen date, Dark Sky Window gives the longest stretch of astronomical darkness with the Moon below the horizon. The Moonlight Impact Calculator shows how strongly the Moon is affecting the sky right now, and Darkest Nights This Month by Moon Phase ranks the nights of the current month by their moonless dark: how bright the Moon is and how much of the dark hours it is up. The Milky Way Season Planner scores each night of a month with the Moon's brightness and position during the core hours built in. Moon Phases explains when each phase rises and sets.

The weather: rainy seasons decide more nights than the sky

Guyana has two climates for stargazing. According to the FAO Drought Portal's Guyana case study, northern (coastal) Guyana has two wet seasons, mid-April to the end of July and mid-November to the end of January, and two dry seasons, August to October and February to March. Southern Guyana, including the Rupununi around Lethem, has one wet season from April to August and is generally dry the rest of the year. (The CIMH Caribbean climate profile puts the start of the southern wet season in May.)

| Month | Coast (Georgetown) | South (Lethem, Rupununi) | Core hours (Georgetown) | Best bet | |---|---|---|---|---| | February | Dry | Dry | 1.6, pre-dawn | Short pre-dawn sessions, coast or interior | | March | Dry | Dry | 3.4, pre-dawn | The best dry-season month for the pre-dawn core | | April | Dry, then wet from mid-April | Wet from April or May | 5.1, mostly pre-dawn | Early April, before the rains | | May | Wet | Wet | 7.0 | Go on clear nights only | | June | Wet | Wet | 8.5 | The most core hours, the fewest clear nights | | July | Wet | Wet | 7.1 | Watch for breaks late in the month | | August | Dry | Wet | 5.2, evening | The best dry-season month on the coast | | September | Dry | Dry | 3.5, evening | Good on the coast and in the interior | | October | Dry | Dry | 1.7, early evening | Short evening sessions |

The awkward fact is that May, June and July give the most core hours and the fewest clear nights. The practical season on the coast is the dry-season evenings of August to October and the dry-season mornings of February and March. In the interior the dry season covers September and October evenings and February and March mornings, and a wet-season night can still clear.

On the coast, when do core time and the dry season overlap?

• May to July
• August to October evenings, and February and March mornings (the right answer)
• December and January
• Never

The practical season on the coast is the dry-season evenings of August to October and the dry-season mornings of February and March.

Two more tropical problems follow the core:

• Dew. On clear, humid nights lenses fog after midnight, which is exactly when the pre-dawn core is up. Check the Dew Risk Calculator and read the Dew and Monsoon Stargazing Playbook.
• Haze. Coastal haze and smoke dim the low southern sky where the core rises and sets. Stargazing Weather shows transparency (haze) as well as cloud.

Check the night itself with the Tonight Observing Score or the city pages for Georgetown and Lethem.

Where to look

The core rises in the southeast (about 120° azimuth), crosses due south at its highest, and sets in the southwest (about 240°). In the pre-dawn months look southeast to south in the hours before dawn. In the evening months look south to southwest after dusk.

The core's path over the southern horizon: where it rises, where it is highest and where it sets, month by month.

You need an open southern horizon and a dark sky to the south. From a bright suburb only a faint band shows overhead, so darker sites matter more than the month. Find one on the Bortle Map and read What Is the Bortle Scale? and Dark Skies in Guyana.

Plan a Milky Way night in six steps

1. Pick the month from the tables above, or open the Milky Way Season Planner for your site.
2. Pick nights near new Moon and check the exact moonless hours in Dark Sky Window.
3. Check cloud and rain with the Tonight Observing Score a day ahead and again before you leave.
4. Choose a darker site with an open southern view on the Bortle Map.
5. Bring dew protection if the forecast humidity is high.
6. For photos, turn the plan into shots with the Milky Way Field Guide and read Milky Way Photography from Guyana.

For the four checks to run on the night itself, see How to See the Milky Way.

How these numbers were made

• Software: astronomy-engine 2.1.19, the library the site's tools use.
• Sites: Georgetown (6.80° N, 58.16° W) and Lethem (3.38° N, 59.80° W), at sea level, with times in America/Guyana (UTC-4).
• Target: the galactic core at right ascension 17h 45.6m, declination -28° 56' (J2000, galactic longitude and latitude 0°), the same point the Milky Way Season Planner uses, precessed to each date.
• Rule: every 5 minutes of each night, the time counts when the Sun's centre is more than 18° below the horizon and the core is at least 15° up. The Moon counts as up when its centre is above the horizon, the same rule Dark Sky Window uses.
• Averaging: hours are averaged over every night of each month in 2026, 2027 and 2028. The sky numbers barely change from year to year; the Moon figures change, which is why they are averaged. The core windows are for the 15th of each month in 2026.
• Weather: FAO Drought Portal, Guyana case study, and the CIMH Caribbean Regional Climate Centre country profile for Guyana.

Related

• How to See the Milky Way
• How to Use the Milky Way Season Planner
• Milky Way Photography from Guyana
• Dew and Monsoon Stargazing Playbook