The HELIOSTAR 100Hα is a premium high-performance 100mm hydrogen-alpha solar telescope designed for serious solar observers and imaging enthusiasts, boasting an exceptional performance of 0.5 Angstrom or better. The Heliostar 100Hα is a precision tool for solar astronomy, offering a full suite of accessories including a 22mm 70° wide-angle eyepiece, solar zenith prism, and solar guider.

Hydrogen-alpha solar observing allows you to unlock the incredible dynamics of surface of the Sun far beyond what a white light solar filter can deliver. From solar prominences on the limb of the Sun (often mistakenly called 'flares'), to active sunspot regions, bright plage patches, surface granulation, wispy, snake-like plasma filaments, and more, the star of the solar system is yours to capture in breathtaking views and images. When viewing the Sun in the narrow H-alpha bandwidth, the observer is rewarded with thrilling, awe-inspiring real-time views of our nearest star in it's full fiery majesty, seething with activity.

The HELIOSTAR-100Ha uses multiple technologies to protect the human eye during solar observation, including an infrared thermal ray reflection film, a special filter to block heat, and a filter to block UV light from entering, blocking stray light that affects observation. It uses a combination of front and rear filters to allow only monochromatic light with a wavelength of 656.28 nanometres emitted by hydrogen atoms to pass through, whilst blocking other light of different wavelengths. This allows the observation of quite active prominences in the H-Alpha band.

Sky-Watcher's Solis etalon technology allows the Heliostar-100Ha to achieve a 0.5A bandpass without the costly expense and complexity of a second etalon to achieve the same performance. This allows the observer to obtain detailed images of the solar disk right out of the box without any further expense.

The HELIOSTAR-100Ha conforms to and meets the transmission requirements of ISO 12312-2:2015 (Filters for the direct observation of the Sun). Always use in accordance with the instructions and exercise the utmost of caution when viewing the Sun.

Safety Information

Please exercise extreme caution when observing the Sun. Improper usage and practices can result in serious and even permanent eye damage!

Also, the 20mm blocking filter in the removable eyepiece diagonal is part of Heliostar's safety features. Do not use this telescope with any other type of diagonal.