Southern Cross · Dark-sky travel in Australia
Nothing here is expensive. Most bad nights out are caused by cold, a bright moon or a track that was harder to find than expected.
Standing still outdoors after dark is far colder than walking in the same conditions, and clear skies make it colder still. A night that is pleasant at sunset can be genuinely unpleasant by midnight, in any season.
Dress for considerably colder than the forecast minimum and add a layer beyond that. Extremities go first: a hat, proper gloves and warm footwear buy you hours. A blanket over your legs if you are sitting is worth more than another jumper.
The usual failure is arriving warm from a heated car, feeling fine for twenty minutes, and then getting cold faster than you can fix. Put layers on before you cool down rather than after.
One red torch per person, brightness turned low. Red light preserves dark adaptation in a way white light does not, and the difference is not subtle.
Set your phone to its dimmest setting before you leave home, and turn off notifications. A screen lighting up at full brightness is the most common way a group's night vision is destroyed, usually by someone checking a message they did not need to read.
If you are parking near where you will be standing, work out in advance how to kill the headlights and interior lights. Some cars are unhelpfully insistent about staying lit.
Looking up for hours while standing is hard on the neck, and people stop doing it before they mean to. A reclining chair, a camping mat or even a picnic rug changes how long you last and therefore how much you see.
A thermos is the other item that repeatedly justifies itself. Warm drinks do more for morale at two in the morning than any piece of optical equipment.
Binoculars are the most underrated instrument for a southern sky. A modest pair shows star clusters, the structure of the Milky Way and the Magellanic Clouds far better than the naked eye, needs no setup, and costs a fraction of a telescope.
For Crux in the evening sky, autumn and winter are the seasons. For the brightest part of the Milky Way high overhead, the middle of the year is best. For comfort, spring and autumn win over winter.
Within the month, the moon dominates everything. The week around new moon is what you want. Around full moon, the sky is bright enough that only the brightest stars survive, and a dark site gives you little advantage.
That combination — an autumn or winter weekend near new moon, with a clear forecast — is the target. There are only a handful of those in a year, which is a good argument for booking one deliberately rather than hoping.
Tell someone where you are going and when you expect to be back, especially if you are heading somewhere without phone coverage. This costs nothing and occasionally matters a great deal.
Driving at dawn and dusk in rural Australia means wildlife on the road. It is the most likely thing to go wrong on the whole trip. Slow down, and if you can arrange to drive in daylight and stay the night, do that instead.
Check fire restrictions and conditions in summer, respect any park closures, and take your rubbish out. Dark-sky sites stay usable because visitors behave; the alternative is gates and locks.
Planetarium apps are genuinely useful for planning and actively harmful in the field if you let them light up your face. Use them at home to work out what will be where, and put the phone away once you are out.
A printed planisphere set for southern latitudes is an old-fashioned answer that works well with a red torch and never runs out of battery. It also forces you to learn the sky rather than following an arrow, which is the difference between knowing where Crux is and being told.
If you do use an app outdoors, most have a night mode that shifts the display to red and cuts brightness. Turn it on before you leave the car, not after you have already blinded yourself.
For planning, the three things worth checking are the moon phase and rise and set times, the cloud forecast for the specific site rather than the nearest city, and the time astronomical twilight ends. That last one surprises people in summer: in the far south, properly dark skies may not arrive until well after ten at night.