Recently Browsing 0 members
No registered users viewing this page.
I've had a lovely session with my Takahashi 100mm refractor tonight. Particularly enjoyable because of the awful weather we seem to have had for the past month - a clear and reasonably dark sky for a decent period seems a real novelty !
I've observed a wide range of targets from Venus at dusk out to galaxies "far, far away". The distant gas giant Uranus, binary stars, star clusters, star formation nebulae, planetary nebulae and super nova remnants have also been visited and admired over the past few hours.
I don't generally observe asteroids that often but tonight one of the largest in the asteroid belt, 4 Vesta, was conveniently positioned in Cetus near the 4th magnitude star Mu Cetus. At magnitude 7.7 4 Vesta was not easy to pick out in the 6x30 optical finder that I was using but the star hop from Mu Cetus was pretty simple so I had no difficulty identifying the star-like point of light amongst a distinct field of background stars. This is the Stellarium view of 4 Vestas position tonight:
And a point of light is all that 4 Vesta appears as in the scope, even at high magnifications. While it is a giant among asteroids, 4 Vesta is a mere 550km or so in diameter and currently a bit over 300,000,000 km from Earth. Stellarium estimates its apparent diameter at .3 of an arc second. I don't know how accurate that is but my 100mm refractor was not going to show its disk, thats for sure !
Despite the modesty of its visual appearance, I was very happy to be observing this little worldlet during its 3.6 year journey around the Sun.
A few years ago NASAs DAWN spacecraft visited 4 Vesa and produced some outstanding imagery such as this example showing the whole asteroid in all its scarred glory. 4 Vesta has clearly been though a lot in it's 4.6 billion year existance:
Now one of my other astro-related interests is meteorites. I currently have a small collection of specimens of the main types built up over the past 12 months or so. Three of my samples are small representatives of a group of meteorites known as HEDs - an abbreviation for Howardite, Eucrite and Diogenite. These are types of achondrite meteorites so were formed through melting and recrystalisation of igneous rocks.
The exciting thing about the HED group of metorites is that we are now fairly certain that they originated from the asteroid 4 Vesta !.
So I thought it would be fun to include some photos of my little specimens of 4 Vesta in this report. Perhaps one day a sample return mission will bring back some material from 4 Vesta so that it can be compared with the meteoric samples that we have ?
Here are some pictures of my specimens of these 3 types. The green cube is 1 cm square for scale - these are small pieces of rock !
Of these 3, only the Tatahouine Meteorite (the greenish one) was actually seen to fall. The other 2 were finds in the north african desert regions. Small fragments of that distant body that I was observing earlier though my telescope. Rather awesome
Last night (Sunday to Monday), a rare event happens. A dim star (mag 10) was occultated by the trans-neptunian asteroid - Huya. The strip where this event was visible passed near by my observatory. So 2:53 local time I was outside to take pictures of this event. It was a very nice night, with clear sky and good temerature for this time of the year. My data obtained by me is already to the profesional astronomers in La Palma, where they will obtain new information about this remote celestial body. I was not alone in this enterprise - another 10 astronomers around the country being involved in the project. I used my data to make a short film of the event with the most important part - occultation itself.
The strip where this event was visible:
This was taken over 4 nights between the 24th September and 6th October as I have a small windows to view objects in the south due to houses and a great big tree getting in the way.
Messier 2, also known as NGC7089 is a globular cluster in the constellation of Aquarius. It is one of the largest know globular clusters and was discovered in 1746 by Giovanni Domenico Maraldi. It lies approximately 55000 ly away and is around 174 ly across.
for those that are interested, Serge from AstroDevices.com has sent me some pics of the encoders he has just finished working on for the Stellarvue M2 mount. Looks like a very professional job to me and I am looking forward to installing them ASAP.
I intend using them with the NEXUX DSC from Astro Devices but you could use the NEXUS II as well. I anticipate the encoders will cost around £290 ish here in the UK after taxes etc. Astrograph.net is the UK distrubuter.
The last image is of my own M2 opened up. Installation should take 15mins I am assured.
I was collecting subs of NGC3628 (one of the Leo triplet) a few nights ago and I am pretty certain I have captured a couple of asteroid trails.
Please see attached photo.
This is just the Luminence subs, 6 off 5 minute subs, then some RGB's and back to luminence again.
Middle left shows some dashes and another set bottom right, just underneath the big, shiny star.
I woulld be interested in trying to identify them, so does anyone know where we can get details of known asteroids? Like a stellarium, or something, for asteroids?
Thanks, in advance.