Fort Union National Monument is a dark sky place in Mora County, New Mexico. It lies in or next to Fort Union National Monument, so park hours, fees and rules apply. The nearest town is Las Vegas, about 40 km (25 mi) away (Fort Union National Monument lies NNE of town). It is certified as an International Dark Sky Park by DarkSky International.
Fort Union National Monument is a unit of the United States National Park Service located 7.7 miles north of Watrous in Mora County, New Mexico. The site preserves the remains of three forts that were built starting in the 1850s. Also visible at Fort Union and from the road leading to it are ruts from the Mountain and Cimarron Branches of the old Santa Fe Trail. The monument has a visitor center containing a historical museum and showing a film about the fort's history. A self-guiding trail leads through remains of the second and third forts. Ruins of the ordnance depot and site of the first fort are visible across the valley to the west. The monument is open 8:00 am to 4:00 pm throughout the year except Thanksgiving (fourth Thursday of November), Christmas Day (December 25), and New Year's Day (January 1). Admission is free.From the Wikipedia article “Fort Union National Monument”, licensed under CC BY-SA 4.0.
Sunrise & sunset directions
At Fort Union National Monument the sunrise point swings a long way through the year: about 60° (ENE) at the June solstice and 119° (ESE) in late December. Sunset moves from 300° (WNW) in June to 241° (WSW) in December, and the midday sun climbs to 78° in summer but only 31° in winter.
| Date | Sunrise | Azimuth | Sunset | Azimuth | Noon sun | Daylight |
|---|---|---|---|---|---|---|
| March equinox (Mar 20) | 7:04 AM | 90° E | 7:12 PM | 271° W | 54° | 12h 08m |
| June solstice (Jun 21) | 5:45 AM | 60° ENE | 8:21 PM | 300° WNW | 78° | 14h 36m |
| September equinox (Sep 22) | 6:49 AM | 89° E | 6:58 PM | 271° W | 54° | 12h 10m |
| December solstice (Dec 21) | 7:07 AM | 119° ESE | 4:50 PM | 241° WSW | 31° | 9h 43m |
Azimuth is measured clockwise from true north (90° = east, 270° = west). Computed for 2026; values change by less than a degree from year to year.
Golden hour & blue hour by month
Certified dark sky places offer protected night skies — plan around the new moon and the Milky Way core season.
| Month (15th) | Blue hour starts | Sunrise | Golden hour ends | Golden hour starts | Sunset | Blue hour ends | Daylight |
|---|---|---|---|---|---|---|---|
| January | 6:42 AM | 7:10 AM | 7:49 AM | 4:31 PM | 5:10 PM | 5:38 PM | 9h 59m |
| February | 6:22 AM | 6:48 AM | 7:24 AM | 5:07 PM | 5:42 PM | 6:08 PM | 10h 54m |
| March | 6:46 AM | 7:12 AM | 7:46 AM | 6:34 PM | 7:08 PM | 7:33 PM | 11h 56m |
| April | 6:01 AM | 6:28 AM | 7:02 AM | 6:59 PM | 7:34 PM | 8:00 PM | 13h 06m |
| May | 5:27 AM | 5:55 AM | 6:32 AM | 7:23 PM | 7:59 PM | 8:28 PM | 14h 04m |
| June | 5:14 AM | 5:44 AM | 6:22 AM | 7:41 PM | 8:19 PM | 8:49 PM | 14h 35m |
| July | 5:26 AM | 5:56 AM | 6:33 AM | 7:40 PM | 8:18 PM | 8:47 PM | 14h 22m |
| August | 5:52 AM | 6:19 AM | 6:55 AM | 7:16 PM | 7:51 PM | 8:19 PM | 13h 32m |
| September | 6:18 AM | 6:43 AM | 7:17 AM | 6:35 PM | 7:09 PM | 7:35 PM | 12h 26m |
| October | 6:42 AM | 7:07 AM | 7:42 AM | 5:51 PM | 6:26 PM | 6:51 PM | 11h 18m |
| November | 6:10 AM | 6:37 AM | 7:15 AM | 4:17 PM | 4:54 PM | 5:21 PM | 10h 17m |
| December | 6:35 AM | 7:04 AM | 7:44 AM | 4:09 PM | 4:48 PM | 5:17 PM | 9h 44m |
Local time (America/Denver), including daylight saving time. Golden hour runs from about −4° to +6° solar altitude, so the morning golden hour begins during blue hour, before sunrise.
Milky Way & night sky
From Fort Union National Monument, the Milky Way core is visible in a dark sky from February through October. June gives the longest window (about 5.7 hours on a moonless night), and the core peaks around 25° above the southern horizon. Our light-pollution model puts the sky at about Bortle 2 (typical truly dark site), which is excellent for astrophotography.
| Month | Core visible (15th) | Hours | Max altitude | Direction |
|---|---|---|---|---|
| January | Below 10° in darkness | — | 0° | — |
| February | 4:48 AM – 5:18 AM | 0.5 | 15° | SE → SE |
| March | 3:53 AM – 5:43 AM | 1.8 | 22° | SE → SSE |
| April | 1:54 AM – 4:54 AM | 3.0 | 25° | SE → S |
| May | 12:00 AM – 4:10 AM | 4.2 | 25° | SE → SSW |
| June | 10:09 PM – 3:49 AM | 5.7 | 25° | SE → SW |
| July | 10:03 PM – 2:23 AM | 4.3 | 25° | SSE → SW |
| August | 9:26 PM – 12:26 AM | 3.0 | 25° | S → SW |
| September | 8:36 PM – 10:16 PM | 1.7 | 22° | SSW → SW |
| October | 7:51 PM – 8:21 PM | 0.5 | 15° | SW → SW |
| November | Below 10° in darkness | — | 2° | — |
| December | Below 10° in darkness | — | -19° | — |
Window when the galactic core is at least 10° high during astronomical darkness on the 15th of each month. Pick nights within a few days of the new moon. Plan exact nights with the Milky Way planner.
Estimated sky darkness: 2 Bortle 2 — Typical truly dark site. The summer Milky Way shows rich structure; clouds look like black holes in the stars. Modeled zenith brightness ≈ 21.89 mag/arcsec².
Weather & best season
Long-term NASA satellite data for this area show October as the clearest month (about 33% average cloud cover) and July as the cloudiest (54%). July is the warmest month and December the coldest, which matters for gear, snow access and how long batteries last at night.
Average cloud cover (%)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| High °F | 64 | 66 | 77 | 83 | 95 | 100 | 100 | 95 | 94 | 84 | 72 | 66 |
| Low °F | 1 | -7 | 6 | 20 | 23 | 36 | 49 | 47 | 30 | 17 | 11 | 2 |
| Precip. (in) | 0.6 | 0.6 | 0.6 | 0.7 | 1.0 | 1.1 | 2.9 | 2.3 | 1.9 | 1.2 | 0.7 | 0.7 |
Monthly climatology for the surrounding 1° grid cell from NASA POWER (MERRA-2). Mountain sites can be colder and cloudier than the cell average.
Photography tips for this dark sky place
- Use the Milky Way table to find months and hours when the core is above the horizon.
- Use red light only and keep it pointed down to protect others' night vision.
- Set focus on a bright star with live-view magnification, then tape the focus ring.
- Use the NPF rule below to choose the longest exposure before stars trail.
- Many parks host star parties and night programs during summer.
- Scout in daylight if you plan to shoot at night or before sunrise.
Season: Milky Way core season runs roughly March to October; winter offers long nights and bright winter constellations.
Suggested gear: Fast wide lens (f/1.4–f/2.8), Sturdy tripod, Red headlamp, Intervalometer. Work out exposures with the depth of field, ND filter and NPF rule calculators.
Permits, drones & access
National Park Service rules. Under federal law (54 U.S.C. 100905), still photography in National Park Service areas needs a permit only when it (1) takes place where members of the public are not allowed, (2) uses models, sets or props that are not part of the location's natural or cultural resources or administrative facilities, or (3) would cause the park to incur additional administrative costs to monitor the activity. Ordinary visitor and most landscape photography needs no permit. Commercial filming rules are separate and have changed in recent years — confirm current requirements with the park before a paid shoot.
Drones: Launching, landing or operating unmanned aircraft (drones) is prohibited in National Park Service units under a 2014 Superintendent's closure (36 CFR 1.5), except where a park has issued specific written approval. Flying from outside the boundary over park land can also violate park rules and disturb wildlife.
Nearby photo spots
Other locations within 40 km of Fort Union National Monument, closest first.
National Wildlife Refuge
Volcano
Mountain Peak
Rock FormationFAQ
When is the best time to photograph Fort Union National Monument?
What time is golden hour at Fort Union National Monument?
Where does the sun rise and set at Fort Union National Monument?
Can you see the Milky Way from Fort Union National Monument?
Do you need a permit to photograph at Fort Union National Monument?
How far is Fort Union National Monument from Las Vegas?
Sources
Location data: DarkSky International (via Wikidata), Wikipedia. Sun, moon and Milky Way times are computed by LWPhoto Atlas for 2026. Climate: NASA POWER. Sky darkness is a population-based estimate (Walker's law), not a measurement. See data sources & licenses.