Show HN: Curiosity – DIY 6' Newtonian Reflector Telescope
Published: (March 8, 2026 at 03:16 AM EDT)
2 min read
Source: Hacker News
Source: Hacker News
Introduction – the Why? Where? How?
Madhav on Computer M & Swarup on Computer S.
Both, looking at their Reddit feeds and getting awed by pictures of the Moon, Jupiter, Saturn, Orion Nebulae, and more, wondered “How much does a decent telescope cost?”
Living in Bengaluru, India, where the months from October to March offer clear skies, we decided to investigate. While browsing Reddit and reading about others’ projects, we discovered the book “Build Your Own Telescope” by Richard Berry (1985). The initial idea was to build a 4‑inch telescope, but we soon upgraded to a 6‑inch Newtonian reflector on a Dobsonian mount.
Hence the name of our telescope: CURIOSITY.
Design Specifications
- Design: 6 in (150 mm) Newtonian Reflector
- Focal Length: 900 mm
- Primary Mirror: Ø 150 mm
- Secondary Mirror: Ø 28 mm (minor axis) & Ø 38 mm (major axis)
- Eyepieces: 25 mm, 9 mm & Barlow lens
Observation Log
| Date (2026) | Target / Note | Eyepiece & Accessories |
|---|---|---|
| 10 Jan | – | – |
| 15 Jan | – | – |
| 23 Jan | Lunar descent (Bengaluru) | 25 mm eyepiece |
| 23 Jan | Photo of team (Madhav left, Swarup right) | – |
| 25 Jan | – | – |
| 27 Jan | – | 25 mm eyepiece & 2× Barlow |
| 30 Jan | Lunar descent (Bengaluru) | 9 mm eyepiece & 2× Barlow |
| 13 Feb | Jupiter | 9 mm eyepiece & 2× Barlow |
| 03 Mar | White‑balance play on a full moon | – |
| 03 Mar | Gallery view on the day of Lunar Eclipse | – |
| 03 Mar | Red moon | – |
| 03 Mar | Lunar Eclipse phases | – |
Additional Notes
- The telescope is easy to carry thanks to bag straps.
- Live‑feed videos (MAG 200×) were recorded during the lunar descent observations on 30‑01‑26, but the video files are not included here.