Seronik - Crux, Eta Carinae
A beautiful stretch of sky near the Southern Cross (Crux) includes the Coal Sack Nebula and the Eta Carinae Nebula to the west. (Gary Seronik)

Under Costa Rican Night Skies

The southern night sky is chockablock with amazing sights that never rise at Canadian latitudes.

Showpieces like the Southern Cross, the Eta Carinae Nebula, Omega Centauri, 47 Tucanae and the Magellanic Clouds are powerful inducements to head south. The dream destination is Australia, where these (and many more) sights ride high in the sky. Unfortunately, a trip to the Land Down Under is expensive and normally requires a commitment of several weeks. However, there is a less costly destination that is relatively easy to get to and doesn’t involve a horrendous time-zone change: Costa Rica.

Seronik - Crux, Eta Carinae
One of the most beautiful stretches of sky lies near the Southern Cross (Crux) and includes the Coal Sack Nebula (the dark region along the southeastern edge of the Cross) and the Eta Carinae Nebula to the west. South of Eta lies the Southern Pleiades, IC2602. (Gary Seronik)

This small Central American nation is in the central time zone and is within easy reach — several major airlines fly into the country’s capital, San José. It has a small, but active group of well-equipped amateur astronomers and some fine observing sites along the west coast. The best time to go is during the dry season, which runs from late November to early May. And having just returned from another stint of stargazing there, I can personally attest to the location’s many virtues.

Last week during the March new Moon, I attended the 11th annual Costa Rican Southern Star Party along with a group of friends. Since our observing spot is at 10 degrees north latitude, in theory we are able to view objects as far south as –80 degrees, though in practice anything lower than –70 is tough to see owing to atmospheric haze.

Jim Stilburn
Victoria, British Columbia, observer and telescope maker Jim Stilburn readies his home-built 6-inch telescope for a night of observing in Costa Rica. (Gary Seronik)

We were able to take in many of the splendid sights mentioned previously. Omega Centauri is especially remarkable. It’s easily visible to the naked eye and is lovely even in binoculars. But in my 8-inch travelscope, it’s a sight beyond belief — a swarm of uncountable stars filling the field of view. The Eta Carinae Nebula is another stunner in just about any instrument. I had fine views in my own scope, as well as Jim Stilburn’s superb home-built 6-inch Cassegrain (which he also designed) and Laura Halliday’s Sky-Watcher 4-inch f/5 achromatic refractor.  Some would argue that this object is even more magnificent than the Orion Nebula. The Eta Carinae Nebula is an intricate, bright glow crossed with prominent dark lanes and punctuated with the brilliant orange star Eta Carinae, all set in an amazingly rich swath of southern Milky Way.

One seldom-appreciated virtue of observing locations near the equator is how good they can be for viewing the Moon and planets. Much of the ecliptic passes directly overhead, which allows for steady seeing conditions. Indeed, it’s an odd sensation to have to point your telescope northward to view Jupiter! We had excellent views of the big planet along with Saturn and Mars on this most recent trip. And because the ecliptic is almost perpendicular to the east and west horizons, spotting Mercury and the very young crescent Moon is a snap. Brilliant Venus dominated the predawn eastern sky, with Mercury trailing behind. In the evening we got to watch a lunar disc, rich with intricate detail, grow from a razor-thin crescent to nearly first-quarter as our week in Costa Rica wore on.

Seronik - Scorpius
The magnificent constellation Scorpius and the rich Sagittarius Milky Way rise high from the latitude of Costa Rica. (Gary Seronik)

Having observed in cold climes much of my life, it’s difficult to describe what a pleasure it is to view Orion while wearing only a T-shirt and short pants. Normally, a night spent exploring this constellation requires bundling up in a down parka and toque! Similarly, seeing Scorpius riding high in the sky in the predawn hours is one of the trip’s highlights. Indeed, thanks to the views I’ve enjoyed from Costa Rica, the celestial scorpion has displaced Orion as my favourite constellation in the entire sky.

I can’t wait to do it all again next year.