Denizens of the Kuiper Belt

Pluto, not a planet, but still super interesting

 The Kuiper Belt is an icy swarm of objects that lie beyond the planet Neptune. As you likely know the first member of the Kuiper Belt to be discovered was Pluto back in 1930. At the time it was given planetary status and was for decades was thought of as being a lone, unique object on the edge of the Solar System. That changed with the discovery of 1992 QB1 (now known as 15760 Albion). Since that discovery several thousand objects have been discovered out beyond Neptune. The discovery of Eris, an object that initially was thought to be larger than Pluto brought the question of Pluto's planetary status into focus. Should it remain classified as a planet or be regrouped with its many thousand neighbors? Pluto really is much more similar to the other worlds that orbit the Sun in the Kuiper Belt than it is to any of the other eight planets of our Solar System.

With that in mind in 2006 the International Astronomical Union decided to take on the issue and in the process invented a new category - Dwarf Planet. They named (promoted?) five worlds to dwarf planet status. One of them comes from the asteroid belt (Ceres) and the other four are members of the Kuiper Belt. They are Pluto, Eris, Haumea and Makemake. (By the way, there are other worlds that should also be given this status, but the IAU shows no interest in adding worlds to the "official" list at this time.)

Eris, Haumea and Makemake were all discovered using the 48-inch Schmidt telescope at Palomar Observatory, a telescope considerably bigger than my little Unistellar eVscope, yet all three of these worlds can be found photographically with small telescopes. 

Earlier this year I realized that I should be able to photograph not only Pluto (the brightest of the bunch), but Haumea and Makemake too. The trick in capturing these worlds is to have a good set of coordinates, a good finder chart (I use SkySafari Pro) and to look at the worlds on two different dates so as to capture their motion in the sky. This makes them easy to distinguish from a star.

By the way, these worlds are far from the Sun, which means that they don't move very fast, so much of their motion that we see is really due to Earth's orbital motion. This changes our perspective on these objects relative to their position as seen against the background stars. A thing that astronomers call parallax.

My first target was Makemake. At the time it was 51.7 times farther from Earth than Earth is from the Sun. That's almost 4.8 billion miles. It's just 888 miles in diameter and has a surface of reddened frozen methane.

Can Makemake be photographed with the 4.5" eVscope? Yes, it can. I observed it on April 1st (no fooling!) and 2nd of this year. I made two exposures of 15 minutes, aligned the images with Photoshop and produced this animated gif showing its motion against the starry background. Can you spot it?

Okay, that's tricky, but it is there. I'll make it easier with this version that is both cropped and annotated:

Bingo!

That gave me the confidence I needed to move on to Haumea. Haumea is an amazing world that is somewhat football shaped, coated with water ice and makes one complete rotation in just 3.9 hours. None of those features would be easily detectable with my little telescope, but they are interesting.

I looked for Haumea on April 9 & 10 of this year when it was 49 times farther from Earth than Earth is from the Sun. That's around 4.5 billion miles away.

Though fainter, it was certainly detectable.

This  image has been cropped from the full frame, but there it is.

Pluto was my next target, but I needed to wait until summer to catch it because I need my sleep. 

Pluto is both larger and closer than Haumea and Makemake, making it much brighter. It's the brightest Kuiper Belt Object, which is certainly why it was the first one discovered.

When I imaged Haumea and Makemake I used 15-minute exposures to catch them. Pluto was obvious with just a two minute exposure. Here it is. Can you spot it?

This image (and the ones of Haumea and Makemake too) is essentially a recreation of the technique that was used by Clyde Taumbaugh at Lowell Observatory when he found Pluto back in 1930, but things were much, much tougher for Mr. Taumbaugh. He had to be outside in the cold Flagstaff air while I was inside my comfortable home. His images were recorded on glass photographic plates that had to be developed and then he had to compare images to look for a moving object on the hundreds of images he took over nearly a year. I had the tremendous advantage of knowing exactly where to look. 

In case you couldn't find Pluto in the image above, here's one that has been zoomed and annotated:

As far as I am able to determine Pluto, Haumea and Makemake are the only members of the Kuiper Belt that can be imaged with an eVscope. The only other dwarf planet that can be seen with an eVscope is asteroid Ceres, which is a very easy target. I have imaged Ceres, but will perhaps post that in a later post on asteroids.