Archive for August 15th, 2009


Getting started for free

August 15, 2009

In the future I will add some more step-by-step how tos on things like recognizing constellations, tracking the phases of the moon, and finding planets and deep sky objects. But I can’t stand, even for a day, having a blog that is supposedly about helping people find their way the sky around that doesn’t actually help them find their way around the sky.

So if you’re chomping at the bit to get going, or you’re just looking for some free astronomy resources, here goes.

Detail of a free star chart from S&T

Detail of a free star chart from S&T

Sky & Telescope has a great 10-page guide called “Getting Started in Astronomy”. It has maps of the night sky and the moon and instructions on how to use them with the naked eye or with binoculars. If you’ve never picked out a constellation on your own and don’t know Aldebaran from Altair, this is Step Zero. There are lots more goodies in S&T‘s Stargazing Basics.

In my humble opinion one of the best free astronomy tools, and the one I use the most, is the free planetarium program Stellarium. You can see what the night sky looks like from any point on the planet, from the deep past to the far future, with optional constellation overlays from cultures around the globe. I use it to see when the moon will be high enough to clear the trees in front of my driveway, to find out what deep sky objects (DSOs) will be overhead at convenient observing times, and to identify things that I’ve stumbled across when I’m just plinking around with binoculars or a telescope.

Stellarium will show you moon phases, but if you really want to see the surface of the moon close up, you can’t do better than the Virtual Moon Atlas (at least without spending any money, and maybe not even then). Includes instructions on how to simulate the view of a spacecraft orbiting the moon, which, if you’re a space nut like me, is going to be irresistible.

If you want to track satellites or spot the International Space Station–which is frequently visible to the naked eye in the early evening!–head on over to Heavens Above for finder charts and instructions on where to look.

For going deeper or just seeing what’s up tonight and for the rest of the week, Almanako is a great resource. It’s more information-dense than most of the rest of these sites, so don’t get flustered if you can’t make sense of it all on your first visit. Things will shake out in time, and the sky isn’t going anywhere.

This is a very, very short list of the free astronomy resources available on the ‘net. If I was so inclined, I could stay busy at this blog doing nothing more than finding and linking to all the good stuff out there. But, as alluded to in the blog title, we all have far too much other stuff to be getting on with. These are the ones I found the most useful when I was getting started, and I use most of them to this day. Even if these particular tools don’t strike your fancy, hopefully they will help you get started on your journey farther up and farther in.


In the footsteps of Galileo

August 15, 2009


This year, 2009, is the International Year of Astronomy. IYA2009 celebrates the 400th anniversary of the first observations of the heavens with a telescope, by Galileo in 1609.

It’s staggering how much Galileo did. If you look at the stuff out there that can’t be seen with the naked eye, he discovered a vastly disproportionate amount of it. Let’s break it down:

Milky Way

GALILEO, 1609-1612
Sunspots (= sun not perfect)
Moon craters and mountains (= moon not perfect)
Venus phases (= Venus circles sun, not Earth)
Jupiter’s moons (= bodies circling Jupiter, not Earth)
Saturn “appendages”
“Star” next to Jupiter (later shown to be Neptune)
Milky Way composed of stars (stars vastly more numerous than previously suspected)
Other bright patches composed of stars (ditto)

Saturn “appendages” are rings – Huygens, 1655
Saturn’s moons – ditto
Uranus – Herschel, 1781
Ceres (first asteroid) – Piazzi, 1801
Neptune recognized as a planet – Galle, 1846
Asteroid belt – several, 1850s
Pluto – Tombaugh, 1930
Rings and moons of outer planets – Voyager probes, 1970s-1980s
dwarf planets beyond Pluto – Mike Brown, 1990s-2000s

Basically, the eras are “stuff everyone knew from when we lived in caves”, “Galileo figures out most of how the solar system works in the space of three years”, and “working out the details”.


It’s all the more impressive when you realize that he was stuck with a 1″ telescope with a field of view of perhaps 5 degrees and a maximum magnification of 20x that, in the memorable words of someone I’ve forgotten, “suffered from every aberration known to optics”. As much as amateur astronomers complain about “department store trash scopes”, the worst plastic monstrosities sold as ‘educational toys’ are still about a thousand times better than what Galileo had to work with for his entire life.

Galileo did more than any other single person before or since to give us a perspective on the universe and our place in it. It’s a perspective that most people have little or no firsthand experience of. In an age when satellite TV is more than a generation old, mobile phones and dashboard computers can guide you around the world using GPS, remote controlled robots explore the surface of Mars, and mankind’s orbital population never drops below 6 (on the International Space Station), average citizens are strikingly disconnected from the wonders of the night sky. Too many people assume that looking up is the exclusive domain of professional astronomers, or that it’s too expensive, or too time consuming, or impossible under the glare of city lights.

2009-04-27 lights at night

None of these assumptions is accurate.

My ambition for this blog is to invite you to be at home in the universe. During the day we see only the world around us, but when darkness falls we can look out, see firsthand, and really get a gut-level understanding of our place in the cosmos. You can learn your way around the sky without spending a dime, and you will never be lost again. An ordinary pair of binoculars, which you probably have stashed in the closet already, will show you most of the wonders that first excited Galileo four centuries ago. If you decide to get a telescope, they are better designed, easier to use, and less expensive than at any time in history.

The slogan of IYA2009 is “The universe, yours to discover.” It is yours to discover, and it doesn’t take a lot of time or money to learn your way around the night sky and see the best and brightest that the heavens have to offer. The journey begins whenever you go out at night and look up. If you’re not sure where to start, that’s okay–that’s what this blog is for. Let’s go!