Ships must practice celestial navigation

Smartphones, Sensors, and Automated Celestial Navigation

• Some argue modern phones have adequate sensors (clock, camera, accelerometer) to support sextant-style navigation or even full star-tracking with software.
• Counterpoint: sensor accuracy and calibration (especially tilt) are limiting, though people already use apps as “fancy calculators” to verify hand calculations.
• Discussion of pixel-level star tracking suggests arcsecond-level attitude is possible; accelerometer noise can be averaged down, but requires time and careful alignment.
• EMP or hacking risk is raised as a reason not to rely on smartphones; others question how much of a ship’s electronics would survive anyway.

Celestial Navigation Methods and Equipment

• Several commenters say the article understates what’s possible at night; lunar distance methods and planetary observations can yield fixes with basic sextant and watch.
• Being without a precise fix for ~12 hours is considered acceptable if dead reckoning is used.
• Bubble sextants are noted as more an aviation tool; marine sextants are available used for a few hundred dollars, so “expensive” is contested.
• Some highlight that the Navy team’s 2 nm track accuracy is actually quite good, especially with many novices.

Backups to GNSS: eLoran, Quantum Nav, and Civil Use

• Strong support for non-GPS backups like eLoran; China’s deployment is cited as an example.
• Quantum navigation is mentioned primarily for submarines; critics note this doesn’t help merchant shipping or civilian timing needs.
• It’s emphasized that any robust strategy must consider civilian infrastructure, not just military users.

Military and Civil Training in Non-Electronic Navigation

• Ground combat units reportedly still practice map-and-compass land navigation; celestial nav on land is seen as rarely necessary.
• Sea navigation is considered more demanding because of lack of landmarks and greater isolation.
• There is praise for maintaining proficiency with sextants, tables, and even slide rules, since skills decay without practice.

Timekeeping, EMP, and Chronometers

• Debate over whether ships need mechanical chronometers versus quartz devices.
• Consensus that non-networked quartz clocks are far more accurate than mechanical ones and can be EMP-hardened with simple Faraday shielding.

Analog vs Digital, Units, and Pedantry

• One subthread distinguishes “digital” (discrete numbers, tables) from “electronic,” noting that much “analog” navigation actually uses digital steps (tables, written numbers).
• Brief debate over whether nautical miles and knots count as “US customary” units and criticism of mixed-unit systems (yards vs nautical miles).

Automated Star Trackers and Historical Systems

• Star trackers on spacecraft and aircraft (e.g., SR‑71, ICBMs) are cited as prior art for automatic celestial navigation.
• Papers and systems like STELLA show star-tracking is mature; the hard part is accurate “down” reference without a visible horizon, requiring good inertial sensors.

Geopolitical Tangents: NATO, Europe, BRICS

• Large subthread veers into NATO burden-sharing, European defense autonomy, and US reliability as an ally.
• Some argue Europe overrelies on US military power; others counter that US also benefits strategically from bases and alliances.
• BRICS is debated: some see it as a serious challenge to Western hegemony, others as incoherent and internally conflicted.
• Concerns about Russian and Chinese ambitions, nuclear proliferation, and information warfare appear, but views diverge sharply on both threat level and Western responses.

Jamming, Races, and “Analog” Culture

• Real-world GPS jamming in areas like the Baltic is mentioned as evidence that GNSS is fragile.
• A retro round-the-world yacht race banning modern electronics is cited as an example that long voyages via celestial and paper navigation remain viable, though demanding.