Tag: telescope

Building a New Telescope

No, I am not talking about TMT. I have something a bit smaller in process. For the first time in many years I am building a telescope. Just a little one.

Makaʻiki
The design for a 6″ f/5 travel telescope Makaʻiki

It has been a while, my cred as an ATM is in jeopardy of being revoked.

When I say a little one I am being serious, a 6″ f/5 is the design specification. This is the same optical specification as Primero, my first telescope. The difference here is in building a travel telescope, something that will fit in carry-on baggage with room for clothing.

I am modelling the telescope off a small telescope built by Brett Schaerer he named WikiKea, a telescope I had a chance to examine at Oregon Star Party a couple years ago. He incorporated a clever focus mechanism into that ‘scope that got my attention.

Brett built his telescope for a trip to Hawaiʻi, thus the Hawaiian influence in the name. I will follow suit and have decided that I am building Makaʻiki, which translates as little eye.

I have generated a full set of plans based on a couple photographs of the original telescope. That exercise itself was fun, I love designing things like this. When these plans are complete, a few details are to be settled during building, I will publish them here on DV.

I have manufactured many of the mechanical parts over the last week. A couple more days will be required to make the remainder. I have sourced many of the materials from my stash in the garage, including the plywood, scraps left over from building other telescopes including Deep Violet. I have found that the selection of stainless steel hardware at the Waimea ACE truly sucks, they are out of stock on everything.

Other parts are coming in from eBay merchants, like knobs and HDPE tape. The optics will likewise be from the eBay, most likely GSO. Later today there will be a stop at Home Depot, I am out of wood glue, the last bit thrown out as it had hardened in the bottle. And unlike the local ACE, their hardware selection is pretty good.

Update! The new ‘scope is complete, you can read more about it here.

Hawaiian Heavens

You might recall a post from back in May describing a night spent on the summit with Jason Chu. He has been accumulating time lapse material for a significant project, capturing the telescopes of Mauna Kea under the beauty of the night sky.

Jason has published a preview of the work. Nice to see it come to life with a decent soundtrack and good editing…

WHAC Visits Subaru

Over the past few years the West Hawaii Astronomy Club has visited nearly every telescope on Mauna Kea. One glaring exception to this is Subaru, the 8.2 meter telescope belonging to NAOJ.

Subaru Telescope
The sun glints over the tall Subaru telescope enclosure
Subaru… Check.

Subaru is the only telescope with an active tour program. By making reservations ahead of time you can visit the interior of the facility with a guide. This made making the arrangements for a tour quite simple, even when the observatories are worried about events on the mountain. We did quite well for tour guides, Rieko Murai and Josh Walawender made the tour a bit better than the usual tour. Josh is well known to the local amateur community, bringing his own small telescopes to observe at the VIS.

The limit for any group visiting the telescope is eight due to practical considerations such as safety. Thus I had set up two tours, using both the 10:30 and 11:30 slots. This allowed most of the club an opportunity to visit the telescope. This did mean we were unable to enjoy the experience together. While we waited for our later tour I led a short walk to some interesting geologic features and one of the ancient ahu that are near the road.

Continue reading “WHAC Visits Subaru”

TMT versus Space Based Alternatives

With the controversy again raging over the TMT we are again seeing complete mis-representation of astronomy in the press and social media. These postings and comments make interesting reading. These show the wide range of feelings in the community. There also seems to be a misunderstanding about the roles of large telescopes in general.

TMT Rendering
An overhead view of the proposed Thirty Meter Telescope, credit TMT Observatory Corporation
The last two decades has seen an enormous advance in our understanding of the universe and its history. We now know the age of the universe, we have discovered planets around other stars, we have learned that ordinary matter makes up only a small fraction of the universe. These represent huge leaps in our understanding and these revelations have come, to the greater degree, from ground based astronomy. Many of these discoveries have been made, or greatly assisted, by the telescopes atop Mauna Kea.

Note: This post was originally written and posted to the old DarkerView blog in August 2008. Re-posted again as it answers on of the common comments in the current episode of the TMT debate. A few edits thrown in to update for the current context seven years after the first publication.

One of the themes that popped up in the comments several times was the idea that space telescopes are where to put the money and the belief that ground telescopes were “obsolete’, thus projects like TMT are not needed. This could not be further from the truth. Yes there are advantages to space telescopes with respect to interference from the atmosphere. But space telescopes face several severe and inherent disadvantages.

Expense

Space telescopes are hugely expensive for what you get. Hubble is a mere 2 meter class telescope. Very small in the terms of modern telescopes. This limits the performance drastically. Hubble can only collect a little more light than a single segment of the current Keck telescope, and Keck has 36 segments in it’s 10 meter mirror. Work out the math and you find that Keck gathers 25 times more light than than Hubble. The new James Webb Space Telescope will be a 6.5 meter telescope. The Thirty Meter Telescope will be 30 meters with 492 segments, thus will gather 28 times more light than JWST.
Continue reading “TMT versus Space Based Alternatives”

Another Peek into CFHT

Upgrades. With 20 year old systems upgrading and replacing old gear is a constant job. It is even worse over at CFHT, their facility is quite a bit older than ours at Keck. Does this mean the telescope is obsolete? No way. most systems have been constantly updated with new technology. But it does take quite a bit of work…

Canada France Hawaii Telescope Upgraded TCS testing from CFHT on Vimeo.