My Experience With a 3" home-made Newtonian Reflector Telescope

Back in the summer of 2006, I finally decided to get my hands on a good telescope that would allow me to properly observe objects that I always wanted to take a closer look at. So, after buying a 400-buck refractor telescope that had a pathetic tripod stand and probably had a magnification of 15X, I deiced that I wanted something better. After some hunting around, my father found out about a man who built his own telescopes out of industrial materials at home - materials as simple as PVC pipes for tubes, and went through rigorous procedures of mirror grinding and polishing and finally collimating it all to get a good end product, despite being basic and home-made.

After making a choice between some telescopes he had for sale, I settled for a 3-inch (aperture) telescope. The built was clearly home-made. The tube was of PVC, the tripod was made of wood, and he provided 2 eyepieces of different resolutions, but overall, it was sturdy and I was certain I did not have to worry about it. For a price as less a Rs. 4000, it was not a bad deal. My first observation subject was the moon. It looked bright enough and details were clearly visible. That made me go in for the buy in the first place. Only later did I realize that even with a telescope, Delhi was not the best place for star-gazing, especially during summers. Except the occasional look at Saturn and its rings (and Titan), or Jupiter and the Galilean moons, the telescope went widely unused. Later that year (one month later, to be exact), dad was posted to Nagpur, so we all had to shift. That made me worried about my telescope and its condition after reaching there. My worries were magnified when the luggage delivery was delayed because the truck carrying it hadn't left Delhi for a long time (which we found out only after some detailed investigation), and heavy rains made it worse as I was not supposed to let my telescope be exposed to water. Nonetheless, my telescope reached safely with no more errors than some in the mirror collimation, which I successfully fixed later.

My experience was best in Nagpur, which had relatively clearer skies throughout the year. Most of 2006 and a 2007 went in spending hours with my eye sticking to the eyepiece of the telescope, looking at random objects, aimlessly looking for the dimmest stars. I later installed Stellarium (covered previously in the blog) which allowed me to track objects in the sky and accurately spot them and look at them through the telescope. I was the happiest when I succeeded in spotting the Orion Nebula, and Venus in its Quarter phase, and Pleiades, and despite having looked at them a hundred times before, there was an undying charm present in Jupiter, Saturn, Orion Nebula, Venus and Pleiades that made me look at them over and over and over again. Nothing beats having a far-away object in space brought much closer for you to look at. Even though it had a lousy magnification of 90X and could magnify just enough to highlight the fact that "Saturn has rings", I treasured my telescope a lot. Later that year, something tragic happened. One of the thin metal plates holding the secondary plane mirror of the telescope broke, rendering it useless Numerous failed attempts to put it back in place left me heartbroken, and dad refused to buy a new one, saying we could fix it. I preferred not to, and wait till I can get a better one.

Till date, I am waiting for that "new, better telescope", but haven't got it yet due to a lot of financial restrictions, but the day I get all the money to buy whatever I want, a telescope will be the first thing I buy.

Posted by rohitchaoji | at 05:03 | 0 comments

The Black Hole War

My recent acquisition apart from some good music is this good book. Although I have only begun reading it, it appears to be rather interesting. It is always interesting to see an alternate theory. This book is written by Leonard Susskind, who did not share the same opinion with Stephen Hawking regarding Black Holes.
Just like 'A Brief History of Time', The Black Hole War is written in a way that it is comprehensible by the general public and does not require higher level of Mathematical understanding, even though it does lunge you deep in thought.

I will write a detailed review once I complete reading this book. Because I usually do not read much, and this book is around 500 pages long, it will take me nearly 2 weeks to do so.

Posted by rohitchaoji | at 23:32 | 0 comments

Edward L. Wright's Cosmology tuorials on the web

Astrophysicist Edward L. Wright's page is a useful source of source of knowledge and can be used to help understand cosmology better. Although I am a supporter of Quasi Steady State Cosmology, I've been reading his tutorials and found them rather good and convincing. You don't have to be a post-graduate student to get an idea of it, and that is the best part.

Here is the link to his Cosmology tutorials page :
Edward L. Wright Cosmology tutorial

Posted by rohitchaoji | at 12:27 | 0 comments

Why I Find First and Second Years of Pure Science Plain Boring

Last year, I decided that it would be a better idea to drop out of the 'engineering' rat race and choose a stream more suitable and comfortable for my career choice. Being more interested in research than application of a particular science for the betterment of mankind, I thought getting myself a BSc degree would be a better idea. But, it turns out that even though I'm not having to slog my ass off 16 hours a day studying and completing assignment while getting Zero knowledge, I wasn't gaining much knowledge either. I was doomed to be in a college with Traditional teaching methods, outdated lab equipments, and a nearly defunct Astro club, which was the only thing I Actually found interesting.
Now, coming to the syllabus, the first year consisted of EVERYTHING we studied in 12th standard, except Mathematics was a little deeper, which I looked at positively at first, but then because the lecturers here believe in mugging things up from a badly printed book that doesn't aim to actually teach anything, it all went over my head. I would say something similar about Electronic Science, but the lecturers were actually good, so I can only blame myself. No complaints with Physics and Chemistry, but it was as if Electronic Science was shoved down my throat in the first year.
Passing the first year with below average results, I awaited the second year, expecting something interesting. Little did I know that its about to as be disappointing. All right, teach us about mathematical methods in Physics but if I really was interested in learning Instrumentation, I would have gone for engineering instead.
3rd year Physics syllabus supposedly consists of Astrophysics as well, so all I can do is wait for it. Till then, the only thing I can do is be disappointed about how much the syllabus sucks and having to learn things I'm not really interested in.

Posted by rohitchaoji | at 01:19 | 1 comments

Revival

This is my first visit to the blog after months. I was suddenly reminded of it after seeing an issue of "Dimensions", which is an Astronomy newsletter (sort of) of the Astro Club in college. I intend to pick it up and write something about it over here.
I also intend to contribute to it because I feel I have been one lazy ass regarding my career lately. Its about time. Also, I desperately need to get myself a high-end reflector scope, which is one of my many far-fetched birthday present desires.

Posted by rohitchaoji | at 00:53 | 0 comments

Stellarium

A very useful tool for amateur astronomers. This helpful software displays the exact positions of objects in the night sky in real time. The graphics are smooth and it gives you the ability to zoom into objects for a closer look.
The features of the software (as listed on the official site), are as follows:


  • default catalogue of over 600,000 stars
  • extra catalogues with more than 210 million stars
  • asterisms and illustrations of the constellations
  • constellations for twelve different cultures
  • images of nebulae (full Messier catalogue)
  • realistic Milky Way
  • very realistic atmosphere, sunrise and sunset
  • the planets and their satellites
  • a powerful zoom
  • time control
  • multilingual interface
  • fisheye projection for planetarium domes
  • spheric mirror projection for your own low-cost dome
  • all new graphical interface and extensive keyboard control
  • telescope control
  • equatorial and azimuthal grids
  • star twinkling
  • shooting stars
  • eclipse simulation
  • skinnable landscapes, now with spheric panorama projection
  • plugin system adding artifical satellites, ocular simulation, telescrope configuration and more
  • add your own deep sky objects, landscapes, constellation images, scripts... 
Get it now from Sourceforge

Also, visit the official site for detailed info : http://www.stellarium.org/

    Posted by rohitchaoji | at 12:28 | 0 comments

    Gravitational Lesnig to be used to measure Age and Size of the Universe

    Source : SLAC

    Using entire galaxies as lenses to look at other galaxies, researchers have a newly precise way to measure the size and age of the universe and how rapidly it is expanding, on a par with other techniques. The measurement determines a value for the Hubble constant, which indicates the size of the universe, and confirms the age of the universe as 13.75 billion years old, within 170 million years. The results also confirm the strength of dark energy, responsible for accelerating the expansion of the universe.
    These results, by researchers at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) at the US Department of Energy’s SLAC National Accelerator Laboratory and Stanford University, the University of Bonn, and other institutions in the United States and Germany, is published in the March 1 issue of The Astrophysical Journal. The researchers used data collected by the NASA/ESA Hubble Space Telescope, and showed the improved precision they provide in combination with the Wilkinson Microwave Anisotropy Probe (WMAP).
    The team used a technique called gravitational lensing to measure the distances light traveled from a bright, active galaxy to the earth along different paths. By understanding the time it took to travel along each path and the effective speeds involved, researchers could infer not just how far away the galaxy lies but also the overall scale of the universe and some details of its expansion.
    Oftentimes it is difficult for scientists to distinguish between a very bright light far away and a dimmer source lying much closer. A gravitational lens circumvents this problem by providing multiple clues as to the distance light travels. That extra information allows them to determine the size of the universe, often expressed by astrophysicists in terms of a quantity called Hubble's constant.
    "We've known for a long time that lensing is capable of making a physical measurement of Hubble's constant," KIPAC's Phil Marshall said. However, gravitational lensing had never before been used in such a precise way. This measurement provides an equally precise measurement of Hubble's constant as long-established tools such as observation of supernovae and the cosmic microwave background. "Gravitational lensing has come of age as a competitive tool in the astrophysicist's toolkit," Marshall said. 

    When a large nearby object, such as a galaxy, blocks a distant object, such as another galaxy, the light can detour around the blockage. But instead of taking a single path, light can bend around the object in one of two, or four different routes, thus doubling or quadrupling the amount of information scientists receive. As the brightness of the background galaxy nucleus fluctuates, physicists can measure the ebb and flow of light from the four distinct paths, such as in the B1608+656 system that was the subject of this study. Lead author on the study Sherry Suyu, from the University of Bonn, said, "In our case, there were four copies of the source, which appear as a ring of light around the gravitational lens."
    Though researchers do not know when light left its source, they can still compare arrival times. Marshall likens it to four cars taking four different routes between places on opposite sides of a large city, such as Stanford University to Lick Observatory, through or around San Jose. And like automobiles facing traffic snarls, light can encounter delays, too.
    "The traffic density in a big city is like the mass density in a lens galaxy," Marshall said. "If you take a longer route, it need not lead to a longer delay time. Sometimes the shorter distance is actually slower."
    The gravitational lens equations account for all the variables such as distance and density, and provide a better idea of when light left the background galaxy and how far it traveled.
    In the past, this method of distance estimation was plagued by errors, but physicists now believe it is comparable with other measurement methods. With this technique, the researchers have come up with a more accurate lensing-based value for Hubble's constant, and a better estimation of the uncertainty in that constant. By both reducing and understanding the size of error in calculations, they can achieve better estimations on the structure of the lens and the size of the universe.
    There are several factors scientists still need to account for in determining distances with lenses. For example, dust in the lens can skew the results. The Hubble Space Telescope has infra-red filters useful for eliminating dust effects. The images also contain information about the number of galaxies lying around the line of vision; these contribute to the lensing effect at a level that needs to be taken into account.
    Marshall says several groups are working on extending this research, both by finding new systems and further examining known lenses. Researchers are already aware of more than twenty other astronomical systems suitable for analysis with gravitational lensing.



     Complete text Copied from Source

    Posted by rohitchaoji | at 12:20 | 0 comments

    The First Post

    Just what the title says. This is the first post of the blog. Nothing special to see here, as I'm giving no introduction of myself. I'll try to post some Astronomy news around here, though.

    Posted by rohitchaoji | at 12:12 | 0 comments