Lighthouse Astrophotography Puerto Rico

These night photographs were captured at Cabo San Juan Lighthouse in Fajardo, Puerto Rico — one of the most scenic historic lighthouses in the Caribbean. Perched above the Atlantic Ocean, the lighthouse provides a dramatic foreground for wide-field astrophotography, combining human history with the natural night sky.

Under dark coastal skies, I photographed the Milky Way region, the Andromeda Galaxy, and winter constellations such as Orion, using a Canon 60Da and a wide-angle lens. The constant ocean wind, salt air, and rotating lighthouse beam made these exposures both challenging and rewarding.

Cabo San Juan (Fajardo) Lighthouse Astrophotography

Canon 60Da,  Wide Angle EF 16-35mm f/2.8L II USM, ISO 3200, f3.5, 30 sec

Light House and Galactic Andromeda - Puerto Rico Astrophotography

Canon 60Da,  Wide Angle EF 16-35mm f/2.8L II USM, ISO 6400, f4, 20 sec

LightHouse Night Sky Astrophotography Puerto Rico — rotating lighthouse beam visible cutting across the sky during long exposure

Canon 60Da,  Wide Angle EF 16-35mm f/2.8L II USM, ISO 6400, f4, 30 sec

The bright diagonal streak visible across the sky is the rotating lighthouse beam, recorded during a long exposure. Unlike aircraft or satellites, the beam produces a broad, continuous band of light that sweeps across the stars as the lighthouse rotates. This effect is especially prominent in coastal astrophotography and cannot be avoided when working close to active navigation lights.

Orion Constellation over Lighthouse Puerto Rico Astrophotography Canon 60Da

Canon 60Da,  Wide Angle EF 16-35mm f/2.8L II USM, ISO 3200, f5, 30 sec

All images were captured during the same Puerto Rico trip, exploring how different celestial targets — from nearby constellations to deep-sky objects like Andromeda — interact with a fixed terrestrial foreground. Lighthouses offer a unique astrophotography subject, symbolizing navigation and light beneath an ancient sky.

Related Astrophotography Posts:

• Puerto Rico Astrophotography – Night Sky and Landscapes
• Arecibo Radio Telescope Astrophotography – Puerto Rico
• Bioluminescent Astrophotography – Puerto Rico

Bioluminescent Astrophotography Puerto Rico

This image combines two rare natural phenomena: the starry night sky above Puerto Rico and the bioluminescent glow of plankton in Laguna Grande Bio Bay. It is the only image in this post that qualifies as true bioluminescent astrophotography.

The stars of Cassiopeia and the Andromeda Galaxy (M31) are visible above the bay, while the bright blue streak in the water was created by bioluminescent plankton disturbed by a passing boat. The glowing trail marks the boat’s engine and wake, leaving a luminous signature across the dark water.

Bioluminescence is a natural light-producing process found in certain living organisms. In tropical bio bays like Laguna Grande, the glow is produced by microscopic plankton called dinoflagellates, which emit blue light when disturbed. This light results from a chemical reaction within the organism and serves as a response to motion, causing waves, wakes, and moving objects to briefly glow in the darkness.

Bioluminescent astrophotography — Cassiopeia and Andromeda over Laguna Grande Bio Bay, Puerto Rico.

This final image is a two-exposure composite, created to accurately represent both the night sky and the bioluminescent water — something that is extremely difficult to capture in a single frame.

The first exposure was taken from a moving boat to record the intense bioluminescent glow created by the engine and wake. The second exposure was captured from the shore, allowing for a longer exposure to properly record the stars and galaxies overhead. Both images were later combined in Adobe Photoshop.

Capture Details

Exposure 1 (Bioluminescence – boat):
Canon EOS 60Da • EF 16–35mm f/2.8L II USM
1.3 sec • f/2.8 • ISO 6400 • Flash fired

Exposure 2 (Night sky – shore):
Canon EOS 60Da • EF 16–35mm f/2.8L II USM
4 sec • f/2.8 • ISO 12800

The use of flash — unusual in astrophotography — proved essential for capturing the peak intensity of the bioluminescent water without washing out the surrounding environment.

The following images were captured directly from the boat and show bioluminescence as night photography. They include visible parts of the vessel and were taken from different angles and distances, illustrating how the glow changes with motion and perspective.

Bioluminescence - Bio Bay Laguna Grande

Canon EOS 60Da • EF 16–35mm f/2.8L II USM • 4 sec • ISO 12800 • f/2.8

Bioluminescence  - Night Photography Puerto Rico

Canon EOS 60Da • EF 16–35mm f/2.8L II USM • 4 sec • ISO 12800 • f/2.8

Bioluminescent astrophotography exists at the intersection of Earth and sky. Moments like this — when plankton responds to motion below while galaxies shine above — remind us that some of the most extraordinary night-time experiences happen not only in the cosmos, but right here on our own planet.

Related Astrophotography Posts

• Milky Way Casting Shadows — Atacama Desert, Chile
  An extreme dark-sky phenomenon where the Galactic Center is bright enough to cast visible shadows on the ground under true Bortle Class 1 conditions.


• Zodiacal Light — High-Altitude Bolivia Astrophotography
  Sunlight scattered by interplanetary dust revealing the plane of the Solar System, visible to the naked eye from the Andes at over 4,000 meters.


• Zodiacal Light — Negev Desert, Israel
  Desert-based zodiacal light observation under exceptionally dry, transparent skies with minimal atmospheric scattering.


• The Milky Way Over the Sailing Stone — Racetrack Playa, Death Valley
  A dark-sky landscape where Milky Way illumination creates subtle brightness contrast across the moving stones and playa surface, revealing terrain under natural night light.


• Rainbow of the Milky Way and the Eternal Baobab — Tanzania
  A rare combination of Milky Way structure, airglow color separation, and ancient landscape under pristine African skies.

Puerto Rico Astrophotography

You might be an amateur astronomer if

you center your vacation time around the New Moon.

--Amateur Astronomer Jokes

These images were captured during my trip to Puerto Rico, where tropical landscapes, low latitude skies, and dark coastal locations create unique conditions for astrophotography. Palm trees, yachts, and ocean waves combine naturally with constellations and the Milky Way, producing nightscapes that look very different from those photographed at higher northern latitudes.

Puerto Rico Astrophotography - Big Dipper constellation, Canon 60Da

Location: Wyndham Grand Rio Mar Beach Resort, Puerto Rico
Canon EOS 60Da · EF 16–35mm f/2.8L II USM · Panorama of 4 frames · ISO 3200 · f/6.3

This image can be used as a practical astronomy question: “What is the latitude of the observer?” Palm trees and the low altitude of the Big Dipper provide strong clues that this photo was taken much closer to the equator than typical northern U.S. locations.

Palm trees and Jupiter in the Puerto Rico night sky

Canon EOS 60Da · EF 16–35mm f/2.8L II USM · 20 sec · ISO 3200 · f/4.5

Palm trees with Orion and Canis Major — Puerto Rico astrophotography

 Canon EOS 60Da, EF16-35mm f/2.8L II USM lens, 20 sec, ISO-3200, F4.5

Yacht astrophotography at Culebra Island Puerto Rico with long exposure night sky

 Long exposure and waves gave such interesting yacht effect
Canon 60Da, EF16-35mm f/2.8L II USM lens, 30 sec, ISO-3200, F4

Near Equator Big and Little Dippers Puerto Rico Nightscape Astrophotography

Canon 60Da, Wide Angle EF16-35mm f/2.8L II USM lens, 10 sec, ISO-6400, F2.8

Northern Pole  Star - Polaris - Laser Pointer Puerto Rico Golf Course Astrophotography

 Canon 60Da, EF16-35mm f/2.8L II USM lens, 14 sec, ISO-3200, F6.3

Culebra Puerto Rico Night Sky

  Canon 60Da, EF16-35mm f/2.8L II USM lens, 30 sec, ISO-3200, F4

Advanced Astrophotography — Tracked Exposure

The final image below represents a different level of astrophotography. Unlike the previous nightscapes, this photograph was captured using a star tracker, allowing a much longer exposure and revealing faint nebulae invisible in short exposures.

Orion, Canis Major and Milky Way - iOptron SkyTracker  Astrophotography Puerto Rico

Barnard’s Loop is often one of the first emission nebulae successfully captured in tracked wide-field astrophotography, making it a natural milestone for beginners moving beyond nightscapes.

Canon EOS 60Da · EF 16–35mm f/2.8L II USM · iOptron SkyTracker
120 sec · ISO 3200 · f/4.0 · Culebra Island, Puerto Rico

At this exposure length, faint objects become visible, including Barnard’s Loop, the Great Orion Nebula (M42), Horsehead Nebula (IC 434), Witch Head Nebula (IC 2118), Rosette Nebula, and Seagull Nebula (IC 2177).

Winter Milky Way images are more challenging than summer Milky Way photography because the galactic center lies on the opposite side of the sky. Tracking with the iOptron SkyTracker made it possible to capture significantly more detail despite limited clear skies.

Related Astrophotography Posts

• Canada Astrophotography (Golf Course Nightscapes)
  Canada Astrophotography — Ontario Golf Course Nightscapes
• Puerto Rico Astrophotography
  Bioluminescent Astrophotography — Puerto Rico
• Radio Astronomy & Observatories
  Puerto Rico Radio Telescope — Arecibo Observatory
• Deep-Sky Astrophotography
  Pelican Nebula Astrophotography (IC 5070 & IC 5067)
• Tracked Astrophotography
  M42 Orion Nebula using iOptron SkyTracker (NYC)

Puerto Rico Radio-Telescope Arecibo Observatory

This post documents a daytime visit to the legendary Arecibo Observatory in Puerto Rico, when the 305-meter radio telescope was still fully operational and open to the public. While these are not night-sky images, Arecibo was one of the most important scientific instruments ever built for radio astronomy, planetary radar, and the study of the ionosphere.

For many amateur astronomers and astrophotographers, visiting Arecibo felt like a pilgrimage — standing beneath a structure that helped characterize asteroids, study pulsars, and expand our understanding of the universe using radio waves rather than visible light.

View of the Arecibo Radio Telescope reflector and suspended receiver platform, photographed from the observation deck

Receiver platform of the Arecibo Radio Telescope, viewed from the observation deck

Flowers in the foreground with the Arecibo Observatory and its suspended receiver platform visible in the background

Anatomy of the Arecibo Radio Telescope

Arecibo Observatory Logo

Galaxy Shop

Arecibo Observatory visitor center

Angel Ramos Foundation Visitor Center inside

Observatory Visitor Center inside

Star planetarium

Milky Way Model

Poster

Observatory Flags

Arecibo observatory and Angel Ramos Foundation Visitor Center

Telephoto zoom of the Arecibo Radio Telescope receiver platform, captured from the observation deck

Anatomy of the Arecibo Radio Telescope in the foreground, with the suspended receiver platform visible behind

Related Posts

• Puerto Rico Astrophotography — Night Sky & Observatories
• Bioluminescent Astrophotography — Laguna Grande Bio Bay
• Lighthouse Astrophotography — Cabo San Juan (Fajardo)

Other Observatory Visits

In addition to Arecibo, I have visited and documented several major astronomical observatories across different regions. Each site reflects a distinct approach to exploring the universe, from optical telescopes to large-scale radio arrays.

• Mauna Kea Observatories — Big Island, Hawaii
  A collection of world-class optical and infrared observatories located above the clouds on Mauna Kea.
• The Karl G. Jansky Very Large Array (VLA) — New Mexico
  A radio astronomy interferometer consisting of 27 movable antennas, studying the universe at radio wavelengths.
• Custer Institute & Observatory — Long Island, New York
  One of the oldest public observatories in the United States, focused on education and amateur astronomy.
• Lowell Observatory — Flagstaff, Arizona
  Historic observatory associated with the discovery of Pluto and continued planetary research.
• Sky’s The Limit Observatory — Joshua Tree National Park
  A public observatory operating under exceptionally dark desert skies, supporting outreach and astrophotography.

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Historical note:
All images in this post were captured while the Arecibo Observatory was fully active and intact. These photographs predate major damage from Hurricane Maria (2017) and the later structural failures in 2020, including the auxiliary cable break in August and the second cable break in November, which led to the telescope’s collapse on December 1, 2020.

Arecibo remains one of the most iconic sites in the history of astronomy. This post is preserved as a visual record of the observatory during its operational years.