The reference sites worth keeping bookmarked, grouped by what you actually use them for. Every link was checked and resolved at the time of writing. Nothing here is affiliated with this guide, and nothing on this page is sponsored.
Before you go out: forecasts
On this coast the forecast is the first decision of every session, and general weather forecasts answer the wrong question. See reading the forecast for how to interpret these properly.
- Clear Sky Charts - the astronomer's forecast, per site, hour by hour: cloud, transparency, seeing, darkness, wind and humidity in one glance. Find the chart nearest to where you actually intend to stand.
- Environment Canada - the conventional forecast, and the source for fog, inversion and mountain-pass conditions, which the specialist charts do not handle.
Space weather and aurora
- NOAA Space Weather Prediction Center - Kp forecasts, real-time solar wind data from the L1 satellites including the all-important Bz component, and the short-term auroral oval model.
- Natural Resources Canada space weather - Canadian forecasts backed by a domestic magnetometer network, which makes its local picture more directly relevant at this latitude.
- NASA solar science - where the eleven-year solar cycle currently stands, and the mission data behind the forecasts.
The aurora page explains what activity levels actually produce a visible display from the Fraser Valley.
What is up tonight
- Stellarium - a free planetarium program showing the sky from your own coordinates at any date and time.
- In-The-Sky.org - ephemerides, conjunctions, oppositions and event guides.
- Heavens-Above - satellite pass predictions calculated for your location.
- NASA skywatching - monthly highlights, written for a general audience and reliable.
Meteor showers
- International Meteor Organization - the annual shower calendar with predicted peak times and rates, and the body that collects amateur observations worldwide.
- American Meteor Society - shower calendars, fireball reporting and observing guidance.
Light pollution and dark skies
- Light pollution map - the standard interactive atlas of sky brightness. Read the light pollution page first for the three ways this map is commonly misread.
- Lorenz light pollution atlas - a modelled world atlas of artificial sky brightness, with historical comparisons that show how a given location has changed.
- Globe at Night - the citizen-science programme that collects naked-eye sky-brightness estimates worldwide. Five minutes, no equipment, and it contributes to a genuinely useful long-term dataset.
- National Park Service night skies - how a very large land manager approaches night-sky protection, with a substantial body of measurement methodology behind it.
Where to go
- BC Parks - provincial park facilities, seasonal opening and access information.
- City of Abbotsford parks - municipal park information, including the valley's dark-sky park.
See observing sites in the Fraser Valley and southern interior for the practical comparison between them.
Images, data and background reading
- Astronomy Picture of the Day - running since 1995, one image a day with a genuine explanation attached, and the best free astronomy education on the internet.
- ESA/Hubble - a very large public image archive with detailed accounts of how each image was assembled from raw data.
- European Southern Observatory - outreach material from the Chilean observatories, exceptionally well produced.
- Astronomy magazine - general amateur astronomy news, observing columns and equipment coverage.
- International Astronomical Union - the authority on astronomical naming, constellation boundaries and object designations.
Building and technique
- Stellafane ATM pages - the standard free reference for amateur telescope making.
- Amateur Telescope Optics - the serious optical theory behind every rule of thumb.
- Astronomical League - structured observing programmes, which are an unexpectedly good way to build skill by giving a session a purpose.
The telescope-making pages on this site are listed together on resources for telescope makers, and astronomy software covers the programs in more detail.
A note on link rot
Astronomy sites are disproportionately maintained by volunteers, institutions with fluctuating budgets, and individuals, so links decay faster here than in most fields. If something above has stopped working, search the organisation's name before concluding it has gone: sites move far more often than they close.