
At 19:27 Pacific Standard Time on Dec. 21, the Sun will reach the southernmost point in its yearly travels, the Winter Solstice.
Afterwards, the Sun will start moving northward again, slowly at first and then faster and faster, and the days will start to lengthen. Spring will still be a long way off, but at least we will know we are en route.
Our remote ancestors were much more dependent on the seasons than we are, so it is not surprising they celebrated the point marking when the days would start lengthening again, and midwinter was past. Christian priests rededicated the winter solstice celebrations to a celebration of Christ's birth.
Then, give or take a calendar adjustment or two, and we end up with Christmas, which raises another issue, namely what would be a good present for the family astronomer(s). Today the range of possible gifts is, er, astronomical, so we will focus on just one important item.
Every budding astronomer wants a telescope. Making the right choice is critical. The wrong choice can result in an expensive and bulky gatherer of dust. The right one can lead to years, or even a lifetime, of discovery. It certainly did for me.
Unfortunately, buying a telescope does not come with the consumer protections that come with other significant purchases. It is actually possible to buy telescopes that are almost useless. A little bit of preparation will be a great help in avoiding disappointment.
If there is a local astronomy club, have a chat with a member or two. Why not buy a useful beginner's astronomy book, such as "Nightwatch", by Terence Dickinson and Ken Hewitt-White, or "The Backyard Astronomer's Guide", by Terence Dickinson and Alan Dyer? Read up on choosing telescopes, and then make the book an additional Christmas present?
Remember, the family astronomer should be able to get his or her telescope outside, set it up and use it without needing ongoing help. That means matching the telescope to the operating environment and to the astronomer.
The number one need is a good, solid mount that makes it easy to install the telescope, point at astronomical objects and then keep it pointed without shaking like a jelly. There are mounts that can be stored in the garage and just trundled outside with the telescope already installed.
The telescope should be easy to carry and set up, and should not be one of those nightmares with knobs and other things sticking out in all directions. They might look hi-tech but they can be a nightmare to set up and operate in the dark.
Astronomical telescopes are multi-use instruments, so getting the best out of them requires the ability to change eyepieces and other accessories as needed for different sorts of observation. Make sure the telescope uses 1.25 or two-inch diameter eyepieces and accessories.
Some telescopes, such as Newtonian reflectors or Dobsonian telescopes, offer large size for moderate prices, but have their eyepieces located at the top end of the telescope, so observing something high in the sky might require standing on a stool. For a young family astronomer , you might want to avoid that. They can also be hard to move around.
For a first telescope, I suggest a simple refracting telescope with an objective having a diameter of at least 75mm, compatible with standard accessories, on a good, solid tripod. Expect to spend at least $100 to $200.
Coming up with the right telescope choice could start a lifetime of pleasure, challenge and learning.
Have a wonderful Christmas, and keep looking up.
•••
• Saturn lies in the south after sunset, with Jupiter in the south-east.
• Venus rises shortly before dawn.
• The Moon will reach first quarter on Dec.19.
This article is written by or on behalf of an outsourced columnist and does not necessarily reflect the views of Castanet.