Stargazing Trek Sagarmatha National Park

October and November are the prime months for this trek: the post-monsoon skies clear sharply after September, humidity drops, and the combination of stable high pressure and dry air above 3,000 m produces the best transparency for naked-eye and telescope viewing. March and April also deliver reliably clear dark skies before the pre-monsoon haze builds in May.

Within any month, the trip is timed around the new-moon window, the five to seven nights centred on the new moon when there is no lunar interference. Swotah schedules departures to coincide with these windows; check departure dates when booking. The monsoon months (June to August) bring persistent cloud, high humidity and frequent rain, which ruins visibility and is not suitable for this trip. December and January have cold, clear nights but sub-zero temperatures at Namche demand a warmer sleeping bag and extra layers. Clear skies are never guaranteed in the mountains regardless of season, so a buffer night at Namche (or a flexible departure) is worth considering for dedicated astrophotographers.

Two permits are required to enter the Sagarmatha National Park area from Lukla. The Sagarmatha National Park entry permit costs NPR 3,000 per person (about USD 23 for foreign nationals) and is collected at the park checkpoint in Monjo on day 1 of the trek. The Khumbu Pasang Lhamu Rural Municipality permit costs NPR 2,000 per person (about USD 15) and is issued at the checkpoint in Lukla before the trail begins.

The old TIMS card is no longer required inside the Khumbu region. Swotah arranges both permits on arrival in Kathmandu once you provide a passport copy, so there is nothing to apply for independently. Fees are current as of 2025 but can be revised by the Nepali government; Swotah will confirm the applicable rates at the time of booking.

Phakding (2,610 m) and Namche Bazaar (3,440 m) both have well-established teahouse lodges that are more comfortable than those on more remote Nepal treks. Phakding has simple but clean lodges with en-suite or shared bathrooms. Namche has a range of options including lodges with hot showers, Wi-Fi and an attached dining room, and the town has bakeries and coffee shops from years of Everest trekker traffic.

The night stargazing session on days 2 and 3 takes place from the lodge terrace or a dark spot above the village, so guests return to their beds rather than camping. A warm sleeping bag rated to at least -10 C is still important: Namche's nights drop well below freezing in October, November, December and January, and even in March and April temperatures fall to around 0 to -5 C at night. Kathmandu accommodation at the start is a comfortable mid-range hotel.

Three meals are included each day on the trek. Teahouse menus in Phakding and Namche feature dal bhat (the Nepali rice-and-lentil staple, always refillable), noodle soups, Tibetan bread, eggs, oatmeal, momos and pancakes. Namche has more variety than most Khumbu stops, with bakeries, pizza and decent coffee.

Aim for 3 to 4 litres of water per day at altitude to prevent dehydration, which worsens any altitude symptoms. Do not drink untreated water; lodges sell boiled water, and purification tablets, a filter straw or a UV pen all work. Carry a 1-litre reusable bottle and refill it at lodges rather than buying single-use plastic bottles, which add waste in the national park. Alcohol slows acclimatisation and should be skipped on the first night at Namche.

Lukla's Tenzing-Hillary Airport sits at 2,840 m in the Solukhumbu district, about 140 km east of Kathmandu as the crow flies, and is the gateway to the Khumbu. Flights from Tribhuvan International Airport in Kathmandu take about 35 minutes on Twin Otter or similar mountain aircraft and operate under visual flight rules only, so early morning departures before cloud builds are standard.

In peak season (April, May, October, November) some operators fly from Manthali Airport at Ramechhap (about 130 km east of Kathmandu by road), which is closer to Lukla and reduces fuel load; Swotah will advise if this applies to your dates. Delays and cancellations due to weather at Lukla are common, so the itinerary builds in the Kathmandu return as a full day with flexibility. Swotah books all domestic flights as part of the package.

Namche Bazaar at 3,440 m gives a dark-sky quality that urban and even most rural sites cannot match. Light pollution, measured by the Bortle scale, runs at Class 2 to 3 in the Khumbu, meaning the Milky Way core casts a detectable shadow on snow, zodiacal light is visible on dark nights, and the sky background is fully dark to the naked eye. The thin, dry air at altitude further reduces atmospheric scattering, making star colours and deep-sky objects clearer than at sea level.

On a new-moon night Swotah guides set up 80 mm and 100 mm refractor telescopes for planetary and deep-sky viewing, and can assist with long-exposure astrophotography using a camera with a manual mode. Visible targets on a clear autumn night include the Andromeda Galaxy (M31) at naked-eye magnitude, the Orion Nebula (M42) through binoculars or a telescope, the Pleiades star cluster, Jupiter and Saturn (when in opposition), and on the clearest nights Uranus with optical aid. The Southern Cross and Magellanic Clouds are visible from the Khumbu's latitude of 28 N.

Sagarmatha National Park covers 1,148 sq km of the high Khumbu in north-eastern Nepal, gazetted in 1976 and inscribed as a UNESCO World Heritage Site in 1979. It contains three of the world's 14 eight-thousanders: Everest at 8,849 m, Lhotse at 8,516 m and Cho Oyu at 8,188 m, along with Ama Dablam at 6,812 m and dozens of smaller peaks. The park protects snow leopard, red panda, Himalayan tahr and more than 110 bird species including the Himalayan monal, Nepal's national bird.

The park's remoteness from Kathmandu (roughly 140 km northeast) and the absence of road access from Lukla upward keep vehicle emissions and artificial lighting out of the upper valleys, which is why the night sky quality remains exceptional. Trekkers pay the park entry permit at Monjo, where rangers also check gear lists and enforce the park's no-wood-burning rule. Carry certified sleeping bag and jacket ratings rather than relying on lodge bonfires at altitude.

Swotah provides a licensed trekking guide and an astronomy-trained assistant for this trip. The trekking guide holds a Ministry of Tourism licence and Wilderness First Aid training. The astronomy assistant has completed a practical astrophotography and telescope-handling course and carries a clinometer, star charts, a green-laser pointer for sky tours and at least one 80 mm refractor telescope for the group.

A porter is included to carry telescope cases and group gear, keeping trekkers' daypacks light for the trail. Telescope time is divided across the group each clear night, and the guide runs a narrated sky tour before the telescope queue, identifying constellations, naming the Sherpa star lore for the major groupings, and pointing out satellites and the International Space Station when passes occur during the session.

A full-frame or crop-sensor DSLR or mirrorless camera with a 24 mm or wider lens at f/2.8 or faster captures Milky Way frames from Namche in 15 to 25 seconds at ISO 1600 to 6400, depending on conditions. A sturdy tripod is essential; ball heads with a friction lock work best on uneven rock ground. Remote shutter releases prevent camera shake on exposures above the camera's self-timer limit.

Phone cameras with a dedicated night or astrophotography mode (Pixel, iPhone 15 Pro and similar) also produce good wide-field Milky Way shots from the Khumbu sky, though they cannot match a dedicated camera for resolution. Batteries drain fast in cold Namche nights; carry two spares per camera and warm them in an inner pocket between uses. The guide identifies the best composition angles for the Milky Way core above the Khumbu peaks each night based on the sky position at that date.

Sagarmatha National Park has strict waste management rules that Swotah enforces on this trip: no single-use plastic inside the park, all solid waste carried out or deposited at designated Namche bins, and no wood burning in lodges above 3,000 m. The 2011 Sagarmatha Pollution Control Committee (SPCC) permit scheme requires trekking groups to carry their waste management documentation, which Swotah provides.

For the night-sky sessions, keep white-light torches off or covered with a red filter once the telescope session starts; even a phone screen at full brightness temporarily ruins dark adaptation for the whole group. The guides use only red-light headlamps and a green laser for sky tours. Tip your guide and porter at the end of the trip: a common guideline is 10 to 15% of the trek cost, paid directly in cash to the staff. Tips represent a significant share of seasonal income in the Khumbu.