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Best Time of Night to See the Northern Lights: Magnetic Midnight by Destination

The aurora peaks around magnetic midnight, not clock midnight. Here is magnetic midnight for Tromsø, Abisko, Rovaniemi, Reykjavik, Fairbanks, and Yellowknife in winter 2026–27, ho…

Nov 10, 2026

How to Take Notes While Watching BJJ Competition Footage (World Pro & No-Gi Worlds)

How to Take Notes While Watching BJJ Competition Footage (World Pro & No-Gi Worlds)

Watch BJJ finals all night and remember nothing in class? Use this 4-line watch template—position, what they did, why it worked, steal for next class—timed for World Pro and No-Gi…

Nov 7, 2026

December 2026 Supermoon: When to See the Cold Moon Rise on Christmas Eve

December 2026 Supermoon: When to See the Cold Moon Rise on Christmas Eve

The December 24, 2026 full moon, the Cold Moon, is the closest supermoon of the year, about 14% wider and 30% brighter than the smallest full moon. Moonrise times vs. golden hour …

Nov 5, 2026

Best Moon Phase to See the Northern Lights: Moonless Nights from December 2026 to March 2027

Best Moon Phase to See the Northern Lights: Moonless Nights from December 2026 to March 2027

A new moon is the safe bet, but in late winter a half moon can stay below the horizon all night or stay up all night. Here are the moonless aurora nights from December 2026 to Mar…

Nov 3, 2026

November Update: A Pro Getting Started Guide and a Few Small Improvements

November Update: A Pro Getting Started Guide and a Few Small Improvements

Meet the November update for Aurora Eos: a getting started guide for Pro subscribers, a faster first location lookup, and a cleanup of the background music.

Nov 1, 2026

See Upcoming Sky Events at a Glance on Home and in Widgets: November Update

See Upcoming Sky Events at a Glance on Home and in Widgets: November Update

Meet the November update for Golden Horizon: a brand-new Sky Events screen, a reorganized Home screen, and iOS widgets rebuilt as small and medium sizes that show observation high…

Nov 1, 2026

November Update: Coral & Red Belts and Champion Counter Techniques

November Update: Coral & Red Belts and Champion Counter Techniques

Meet the November Post Black Belt update: coral and red belts, rank bar color choices, a screen that shows champions' counters alongside each technique, weight class names in your…

Nov 1, 2026

How to Choose a Northern Lights Destination: Tromsø, Abisko, Finnish Lapland, Iceland, Yellowknife, or Fairbanks?

How to Choose a Northern Lights Destination: Tromsø, Abisko, Finnish Lapland, Iceland, Yellowknife, or Fairbanks?

Planning a northern lights trip between November and March? Here's where to go, when, and how many nights to stay. I compare Tromsø, Abisko, Finnish Lapland, Iceland, Yellowknife,…

Oct 31, 2026

Geminid Meteor Shower 2026 in New York: Best Night Is Dec 13, After Moonset at 8:41 PM

Geminid Meteor Shower 2026 in New York: Best Night Is Dec 13, After Moonset at 8:41 PM

The 2026 Geminids peak at 9:00 AM EST on Monday, Dec 14, which is daytime in New York, but the whole night of Dec 13 falls inside the peak window. A crescent moon about 21% lit se…

Oct 31, 2026

Your First BJJ Tournament: Weight Classes, Weigh-Ins, Gi Rules, Points, and a Day-Before and Day-Of Checklist

Your First BJJ Tournament: Weight Classes, Weigh-Ins, Gi Rules, Points, and a Day-Before and Day-Of Checklist

Signing up for your first BJJ tournament? Start with weight classes and how weigh-ins work. Here's a rundown of IBJJF gi rules, points, white belt illegal moves, what to pack and …

Oct 31, 2026

What to Write in a BJJ Training Journal After Class (4-Line Template)

What to Write in a BJJ Training Journal After Class (4-Line Template)

Not sure what to write in a BJJ training journal? Use this 2-minute, 4-line template for after class: worked on, went well, went wrong, next focus. Log positions and techniques, n…

Oct 28, 2026

How to Photograph the Northern Lights with Your Phone: iPhone, Samsung Galaxy, and Pixel Settings

How to Photograph the Northern Lights with Your Phone: iPhone, Samsung Galaxy, and Pixel Settings

Your phone can capture the northern lights better than your eyes can see them. Here are the best settings for iPhone Night mode, Samsung Galaxy Pro mode, and Pixel Astrophotograph…

Oct 26, 2026

Leonid Meteor Shower 2026: When to Watch After Moonset (Nov 17–18)

Leonid Meteor Shower 2026: When to Watch After Moonset (Nov 17–18)

The 2026 Leonids peak on the night of November 17–18, with a first quarter Moon that sets around midnight. Here are moonset times, when Leo rises, and when dawn ends the dark sky …

Oct 26, 2026

What Kp Index Do You Need to See the Northern Lights? A City-by-City Guide

What Kp Index Do You Need to See the Northern Lights? A City-by-City Guide

What Kp do you need to see the aurora where you are? A Kp index chart for Tromsø, Iceland, Yellowknife, Fairbanks, Finland, Helsinki, Edinburgh, Seattle, and more, based on magnet…

Oct 22, 2026

November 2026 Beaver Supermoon: Date, Moonrise Times, Photo Tips

November 2026 Beaver Supermoon: Date, Moonrise Times, Photo Tips

The Beaver Moon on November 24, 2026 is a supermoon. See moonrise times and golden hour for Seoul, Tokyo, London, New York and LA, plus which way to face.

Oct 22, 2026

Best Time to See the Northern Lights in November and December 2026: Moon Calendar and Darkest Nights

Best Time to See the Northern Lights in November and December 2026: Moon Calendar and Darkest Nights

Planning a northern lights trip for November or December 2026? Here are the moon-free dark-sky dates, the full moon weeks to know about, and how to pick the right night with an au…

Oct 19, 2026

Hunter's Moon 2026: When to Photograph the Full Moon Rising at Golden Hour

Hunter's Moon 2026: When to Photograph the Full Moon Rising at Golden Hour

The Hunter's Moon is full on October 26, 2026. Here are the evenings when moonrise lands in golden hour for Seoul, Tokyo, London, New York, and Los Angeles, which direction to fac…

Oct 19, 2026

Reflecting on Two Years as a Full-Time Indie Developer

Stelo: Focus & App Blocker

Reflecting on Two Years as a Full-Time Indie Developer

A look back at two years as a full-time indie developer, from freelance work and digital nomad life to learning to build products around what other people need.

Oct 6, 2026

Stelo for Indie Builders Who Do It All

After five years building solo, I made Stelo to help me switch between development, marketing, and operations—and see how my week was really spent.

Oct 6, 2026

October Update: A Better Read of the Night Sky

October Update: A Better Read of the Night Sky

Connect astronomy alerts with the Monthly Briefing, follow beta sunrise and sunset outlooks, spot golden and blue hour on the solar timeline, and choose weather units by category.

Oct 1, 2026

October Update: Training Records in Health and a Home Screen That Feels More Like Yours

October Update: Training Records in Health and a Home Screen That Feels More Like Yours

You can now save training time logged in Post Black Belt as martial arts workouts in Apple Health and Health Connect, optionally with estimated calories. This update also adds hom…

Oct 1, 2026

Check Out the September Update

Discover more accurate astronomy forecasts, sunrise and sunset viewing scores, planet visibility around twilight, and astronomy alerts.

Sep 8, 2026

Check Out the September Update

September update notes for Post Black Belt, covering Apple Watch and Wear OS widgets, signature-technique instructionals from world champions, more concrete technique exploration,…

Sep 1, 2026

A Photographer's Guide to Perfect Golden Hour Shots

A Photographer's Guide to Perfect Golden Hour Shots

Learn how to find the best light, plan your location, and capture stunning landscape photos during the golden and blue hours with Golden Horizon.

Aug 27, 2026

Why Are Auroras More Common Around the Equinox? A Fall Viewing Guide

Why Are Auroras More Common Around the Equinox? A Fall Viewing Guide

Learn why geomagnetic activity tends to rise around the equinoxes, how the Russell–McPherron effect works, and how to prepare for the 2026 fall aurora season.

Aug 24, 2026

Building and Shipping Apple Watch and Wear OS Apps with Expo

Sportling: Workout Calendar

Building and Shipping Apple Watch and Wear OS Apps with Expo

How I kept an Expo app while building and shipping native Apple Watch and Wear OS apps, WidgetKit complications, and Wear OS tiles.

Aug 15, 2026

Your Workout Space on Your Wrist: The Sportling Watch App

Your Workout Space on Your Wrist: The Sportling Watch App

Sportling now brings your pixel art workout space, countdowns, and recent activity to Apple Watch and Wear OS.

Aug 15, 2026

Building My Own Pixel Art Workout Widget after BJJ, Running, and Weight Training

Sportling: Workout Calendar

Building My Own Pixel Art Workout Widget after BJJ, Running, and Weight Training

Design your own pixel space, track attendance with heatmaps and countdowns, and customize home screen widgets 100% offline.

Aug 4, 2026

August 2026 Sky Highlights and New Features

August 2026 Sky Highlights and New Features

Explore the August 2026 solar eclipse, lunar eclipse, and six-planet parade, plus new Lock Screen widgets and the Moon direction map in Golden Horizon.

Aug 2, 2026

Introducing the August Update

The August Post Black Belt update adds voice journaling and refreshed monthly, quarterly, half-year, and yearly recaps for reviewing your training frequency, time, technique hasht…

Aug 1, 2026

Plan Aurora Viewing with Polar Day and Polar Night

Plan Aurora Viewing with Polar Day and Polar Night

Learn how polar day and polar night affect aurora viewing, then use Aurora Eos to check annual darkness and the time remaining until seasonal transitions.

Jul 11, 2026

Omija: Korean Food in Season

Find the Sun Direction on the Map

Learn how to use Golden Horizon's Sun Direction Map to check sunrise, selected-time, and sunset directions before you head out.

Jul 11, 2026

Taste Korea in Season

Discover Korean food through seasonal ingredients, traditional calendar dishes, and weather-based recommendations with Omija.

Jul 11, 2026

Check Full Moon Names in Widgets and More Monthly Astronomy Events

Check Full Moon Names in Widgets and More Monthly Astronomy Events

Check cultural full Moon names in Golden Horizon widgets, explore more monthly astronomy events, and use the Moon as a guide for finding planets.

Jul 3, 2026

Check Out the July Update

July update notes for Post Black Belt, covering competition and medal records, quick attendance check-ins, random technique hashtags, promotion-day journals in Belt Storage, and m…

Jul 1, 2026

Check Monthly Highlights and Cultural Full Moon Names

Check Monthly Highlights and Cultural Full Moon Names

Explore Golden Horizon's monthly highlights and cultural full Moon names to notice something new in the sky every day and every month.

Jun 10, 2026

Get Geomagnetic Storm Forecast Alerts

How to read NOAA 3-Day Forecast Kp and G-scale data, and how to set up geomagnetic storm forecast alerts in Aurora Eos.

Jun 8, 2026

June Update: New Features and Improvements

June Update: New Features and Improvements

June update notes for Post Black Belt, covering the new Home screen, holiday support, My Hashtags improvements, 2026 competition data, and more.

Jun 1, 2026

Check Planet, Blue Moon, and Solar Eclipse Events

Check Planet, Blue Moon, and Solar Eclipse Events

Check rare astronomical events like special Moon events, planets, solar eclipses, and lunar eclipses during golden hour.

May 12, 2026

May Update: Improvements Based on Your Feedback

May Update: Improvements Based on Your Feedback

May update notes covering new techniques and usability improvements based on user feedback.

May 11, 2026

Get Forecasts with More Accurate Locations

Get Forecasts with More Accurate Locations

How to get more accurate location-based aurora forecasts in Aurora Eos with city search, map selection, exact coordinate input, and custom saved locations.

May 9, 2026

Diary Favorites and Technique Favorites

Save the journals and techniques you revisit often, and look back on your jiu-jitsu journey more easily.

May 1, 2026

Building Personalized Sunset/Sunrise Push Notifications with Expo + Firebase

Building Personalized Sunset/Sunrise Push Notifications with Expo + Firebase

A practical walkthrough of a personalized sunset/sunrise notification pipeline using Expo, Firebase Functions, Firestore, Cloud Tasks, and FCM.

Mar 26, 2026

Optimizing 3D, Animation, and Chart Performance in an Expo Mobile App

Optimizing 3D, Animation, and Chart Performance in an Expo Mobile App

A practical walkthrough of optimizing 3D visualization, 2D animation, and solar wind charts in a React Native (Expo) app.

Mar 26, 2026

3 MCPs That Reduced Repetitive Operations in Solo App Development

Pabal

3 MCPs That Reduced Repetitive Operations in Solo App Development

Three core Pabal MCPs that cut repetitive app operations and helped me stay focused on product development.

Mar 26, 2026

Build Your Own Custom Screensaver Collection

Ink On: E-Ink Calendar

Build Your Own Custom Screensaver Collection

Build e-reader lock screen combinations with your own uploaded images.

Feb 28, 2026

Build Your Own Aurora Forecast Widgets

A quick guide to customizing Aurora Eos widgets with key forecast signals on your home and lock screens.

Feb 27, 2026

Build Your Own Jiu-Jitsu Widgets

An overview of new widget features to keep your jiu-jitsu routine close: D-day settings, a monthly dot calendar, and home/lock screen widget options.

Feb 27, 2026

A 1-Year Review of Maintaining iOS and Android Widgets with Expo

A 1-Year Review of Maintaining iOS and Android Widgets with Expo

My experience developing and maintaining cross-platform widgets in an Expo environment using @bacons/apple-targets and react-native-android-widget.

Feb 21, 2026

Building an E-Reader Screensaver App with Expo

Ink On: E-Ink Calendar

Building an E-Reader Screensaver App with Expo

The story of developing Ink On, a minimalist E-Ink screensaver app, and technical challenges faced using Expo and React Native

Feb 21, 2026

Living as a Digital Nomad in Seoul for 6 Months

Living as a Digital Nomad in Seoul for 6 Months

A half-year in Seoul as a digital nomad: where I stayed, worked, ate, and how I spent my days.

Feb 10, 2026

How to Interpret Aurora Conditions: From Solar Wind and Geomagnetism to Earth Weather

How to Interpret Aurora Conditions: From Solar Wind and Geomagnetism to Earth Weather

A guide to reading aurora conditions in order: solar wind, geomagnetic activity (Kp, Bz, Ovation), and local weather. Plus tips for using Aurora Eos.

Jan 23, 2026

Check Aurora Forecast Home Screen Widget

Check Aurora Forecast Home Screen Widget

How the Aurora Eos 3-Day Kp Forecast home widget combines Kp and Ovation to help you time your aurora hunts better, right from your home screen.

Jan 13, 2026

2026 New Year Plans

Setting goals and plans for the new year 2026.

Jan 5, 2026

20 Questions to Look Back on 2025

As the year comes to an end

Dec 31, 2025

Pabal

Pabal: An App Deployment and Maintenance Automation Tool for Solo Developers

Learn about Pabal, a tool created to solve the bottlenecks in app deployment and maintenance operations, with real-world use cases.

Dec 22, 2025

Seeing My First Aurora with My Own App

A developer who loves astronomy shares the experience of seeing their first aurora in Canada using a self-built aurora prediction app

Dec 19, 2025

Make Today's Techniques Your Own

A closer look at the renewed Techniques tab, hashtag-based recommendations, and personal technique tracking that help turn what you learned today into your actual game.

Aug 22, 2025

Log Double Sessions, Celebrate Your First Day, Choose Icon Themes, and View All Journals

A quick update on requested features: multi-session training logs, start-date celebrations, icon themes, and a full journal list view.

Jan 27, 2025

Traveling halfway around the world to Porto to create a fresh To Do App in two weeks

Tile Do: Todo list

Traveling halfway around the world to Porto to create a fresh To Do App in two weeks

Discovering inspiration in Azulejo tiles to create Tile Do, a unique to-do app that blends Portuguese design aesthetics with modern productivity tools.

Dec 2, 2024

Introducing Poble, the World's First BJJ AI

Introducing Poble, the World's First BJJ AI

Introducing the Poble AI MVP with automatic technique hashtag generation built from real journal workflows in Post Black Belt.

Oct 12, 2024

Building a BJJ App While Training Jiu-Jitsu in Taipei

Building a BJJ App While Training Jiu-Jitsu in Taipei

A story about visiting an overseas gym again after half a year.

Sep 15, 2024

Building a BJJ App While Training Jiu-Jitsu in Chiang Mai