The jump from 4 inches to 5 inches of aperture is where deep-sky observing starts to get serious — spiral arms in M51, the dark lane in M82, and globular clusters that resolve into individual stars instead of cotton balls. The Explore Scientific AR127 steps up to a 5-inch aperture with 55% more light-gathering than the AR102, with an 8x50 finderscope, 2" dielectric diagonal, and dual-speed Crayford focuser included at a price that makes serious aperture accessible.

Key Features

• 127mm (5") Air-Spaced Crown-and-Flint Doublet – Classic achromatic design with fully multi-coated optics delivers bright, high-contrast views with 0.91 arcsecond resolution and a 13.0 limiting magnitude — 55% more light than a 102mm refractor
• Fast f/6.5 Focal Ratio – 826mm focal length provides wide-field deep-sky views of galaxies, nebulae, and star clusters while still resolving lunar craters and planetary detail at moderate magnifications
• 2" Dual-Speed Crayford-Style Focuser – Zero-image-shift design with 10:1 fine focus ratio and adjustable tension for smooth, precise focusing at any magnification
• 8x50 Straight-Through Finderscope Included – High-quality optical finder with quick-release bracket for fast, accurate star-hopping — no additional purchase needed
• 99% Reflective 2" Dielectric Diagonal Included – Premium diagonal with brass compression ring maximizes light throughput and contrast right out of the box
• Durable, Outreach-Ready Construction – Solid tube, reliable optical alignment, and a built-in carry handle make this scope a natural choice for astronomy clubs, educators, and public star parties
• Cradle Rings with Carry Handle – Felt-lined rings provide secure mounting and easy balance adjustments, with a built-in handle for safe transport
• Vixen-Style Dovetail – Compatible with most alt-azimuth and equatorial mounts for flexible setup options

Ideal For

• Visual observers who want more aperture without paying for an APO — the 127mm doublet gathers 55% more light than a 102mm refractor and resolves to 0.91 arcseconds, revealing structure in galaxies, nebulae, and star clusters that smaller scopes can't show — all for a fraction of an ED refractor's price
• Star party and outreach organizers who need an impressive, reliable scope that draws crowds — the 5-inch aperture delivers bright views that make the Moon and deep-sky objects pop for first-time observers, and the included finderscope, diagonal, and Crayford focuser mean you're set up in minutes
• Deep-sky enthusiasts who enjoy sweeping wide fields for galaxies, nebulae, and star clusters — the fast f/6.5 focal ratio and 13.0 limiting magnitude bring fainter objects within reach under dark skies
• Observers stepping up from a 70–102mm refractor who want a meaningful jump in brightness, resolution, and reach — the AR127 is the sweet spot in the AR Series, offering noticeably more capability than the AR102 while staying portable enough for regular use at 15.6 lbs

Accessories & Compatibility

• Explore Scientific Twilight I Alt-Azimuth Mount – Smooth manual tracking with adjustable tilt angle — a natural pairing for visual observing and grab-and-go sessions
• Explore Scientific EXOS2-GT Equatorial Mount – GoTo motorized mount with PMC-Eight system for automated object tracking — ideal for observers who want to explore the full catalog
• Explore Scientific Field Flattener (f/5–f/7) – Corrects field curvature for sharper edge-to-edge star fields in imaging applications
• Explore Scientific Soft-Sided Telescope Case – Padded protection for safe transport to dark-sky sites and star parties

Want even more aperture? The AR152 steps up to 152mm for the brightest views in the AR Series with a full 6 inches of aperture. Looking for a lighter grab-and-go option? The AR102 delivers the same optical design at 11.5 lbs and 25.5" of tube. Want color-free APO performance? The ED102 Essential Series steps up to an air-spaced triplet with HOYA FCD1 extra-low dispersion glass, eliminating the chromatic aberration inherent in achromatic designs.

Note: No eyepieces are included — the AR127 is designed for observers who want to choose their own. See our recommended eyepieces below.

Recommended Eyepieces

We recommend the Explore Scientific 52° Series Waterproof Eyepieces — each is fully sealed, nitrogen-purged, and built for years of reliable use:

• 25mm (33x) – Wide-field scanning of the Orion Nebula, Andromeda Galaxy, and Pleiades star cluster with a bright, expansive view
• 20mm (41x) – A versatile mid-range magnification for exploring galaxies, nebulae, and open clusters with good detail and field of view
• 10mm (83x) – Sharp planetary views and double-star splitting, with bright, contrast-rich deep-sky detail
• 4.5mm (184x) – High-power lunar and planetary detail — Saturn's rings, Jupiter's cloud bands, and intricate lunar craters

If you're starting out, the 25mm delivers bright, sweeping views that make deep-sky objects easy to find. Add the 10mm for a versatile mid-high power option, then build from there.