Building a Telescope, in Low Cost

AASTRO Monthly session on home-made telescopes held at Thiruvananthapuram on 2nd June could attract a good gathering of astronomy enthusiasts. Mr. A. P. Prabhakaran lead the session with the aid of a 4" telescope which he had made with his own hands. He could convince the audience that we can build our own telescope at home spending only half the amount required for a commercially made one.



Quoting his own words:

The choice as to buying a commercially made telescope or taking the challenge of making one your own  is a personal choice.  It may be better for a beginner astronomer to build a suitable telescope. Making a telescope of your own is easy and very educational with the end product being a great learning tool where an amateur will learn astronomy and associated science.  So build your own telescope from chosen parts according to your budget and what you wish to make yourself.  Choices between using different types of optics are yours.

Dobsonian telescopes are probably the easiest to make.    The parts required to build your own telescope include Mirrors, Tube, Lenses & Mounting system.  The telescope which I have demonstrated includes the following parts –

Primary mirror                          - 100 mm dia, 100 cm focal length

Secondary mirror                      - 25mm dia

Size of tube                             - 140mm dia, 120 cm long.

Miscellaneous                         - Primary mirror cell, secondary holder, focuser etc.

All the parts are available from M/s Tejraj & Co, Mumbai.  With the aid of this telescope I was able to view  planets including Jupiter & its 4 moons, Saturn and Orion nebulae.  The approximate cost is Rs. 7,000.  A commercially made dobsonian will definitely cost double.

PLANET ROUND UP_JUNE 2011

SATURN: The ringed world is getting closer to Porrima (Gamma Virginis) this month. The planet will be closest (just 15’ 24”) from Porrima on June 9th.

NEPTUNE: Shines at magnitude 8 in the constellation Aquarius. Neptune turns retrograde from June 3rd.

URANUS: Uranus in Pisces shines at magnitude 5.87. Uranus is at Western Quadrature on June 26th.




JUPITER: Will rise around 3:40am during the month’s beginning. The planet will climb up well in the eastern pre-dawn sky for observers. Jupiter will be 5.5 degrees of the Crescent Moon on June 26th.

MARS: Will remain low in the eastern pre-dawn sky. Mars will be paired with Pleiades, being within 5 degrees, during 16th to 22nd June. Mars is within just 3.5 degrees of a Crescent Moon on June 29th.

VENUS: Is the brightest star of dawn this month. From June 6th to 10th, it will be paired with Pleiades very low in the East. On June 30th Venus will be within 3 degrees of a Waning Crescent Moon very low in the east near the horizon just before dawn.

MERCURY: Is at superior conjunction on 13th.



v s / AASTRO

ASTRONOMICAL EVENTS FOR JUNE 2011

June 1-2: Partial Solar Eclipse for far northern latitudes northeast Asia, the partial eclipse of the sun will be visible from northern Siberia, northern Alaska, northern and eastern Canada,Greenland, Iceland, and northern Scandinavia.

June 2: New Moon

June 7: A Waxing Crescent Moon within 6.5 degrees of Regulus

June 9: First Quarter Moon

June 9: Saturn is just 15’24” of Porrima

June 11: The Moon 3 degrees of Spica

June 13: Mercury Superior Conjunction

June 14: The Moon occults Rho Ophiuchi. The event starts at 9:18pm and ends at 10:00pm.

June 15-16: Total Lunar Eclipse. Penumbra at 17:23 U.T., Totality at 20:12 U.T. and ends at 23:02 U.T. For local (India), the timings are, Penumbra at 10:57pm (15 June), Umbra at 11:55pm and Totality at 1:42am (16 June). For locals, this eclipse will end at 4:30am.




[caption id="attachment_1078" align="aligncenter" width="542" caption="Sketch of the June 15 lunar eclipse."][/caption]




June 21: Summer Solstice

June 23: Last Quarter Moon

June 26: Uranus Western Quadrature

June 26: Jupiter and a Waning Crescent Moon are just 5.5 degrees apart in the East before dawn

June 28: A Waning Crescent Moon (12% illuminated) within 4.5 degrees of Pleiades in the East just before dawn

June 29: A Waning Crescent Moon (6% illuminated) within 3.5 degrees of Mars in the East and very low before dawn

June 30: Watch the Waning Crescent Moon (2% illuminated) just within 3 degrees of Venus very low in the East at the time of dawn


V S/AASTRO


സമ്പൂര്‍ണ ചന്ദ്രഗ്രഹണം ജൂണ്‍ 15ന്

നൂറ്റാണ്ടിലെ ഏറ്റവും ദൈര്‍ഘ്യമേറിയ ചന്ദ്രഗ്രഹണം ഈ മാസം 15ന്. ഈ ദിവസം സൂര്യനും ഭൂമിയും ചന്ദ്രനും ഒരു നേര്‍രേഖയിലെത്തുന്നതോടെ ഭൂമിയുടെ നിഴല്‍ ചന്ദ്രനെ പരിപൂര്‍ണമായും മറയ്ക്കും. ഇന്ത്യയിലുടനീളം ഇതു കാണാനാവു.



ഭൂമിയുടെ ഇരുണ്ട ഭാഗത്തേക്കു ചന്ദ്രന്‍ നീങ്ങുന്നതോടെ അതൊരു ചെമ്പന്‍ ചുവപ്പുനിറത്തിലേക്കു മാറും. രാത്രി 11.53ഓടെയാണ് ഇതാരംഭിക്കുക. അടുത്ത ദിവസം പുലര്‍ച്ചെ 3.30ഓടെ ഗ്രഹണം അവസാനിക്കും. ഇന്ത്യയെ കൂടാതെ പശ്ചിമേഷ്യ, തെക്കന്‍ യൂറോപ്പ്, വടക്കന്‍ ആഫ്രിക്കന്‍ പ്രദേശങ്ങളിലും ഈ അസുലഭ കാഴ്ച ലഭ്യമാവും.

നൂറ്റാണ്ടിലെ ഏറ്റവും കറുത്ത ചന്ദ്രഗ്രഹണമായിരിക്കും ഇത്. ഇതിനു മുമ്പ് 1971 ആഗസ്ത് 6നാണ് ഒരു ചന്ദ്രഗ്രഹണം ഇന്ത്യയിലുണ്ടായത്. ഈ വര്‍ഷത്തെ അവസാന ചന്ദ്രഗ്രഹണം ഡിസംബര്‍ 10നാണ്. യുറേഷ്യ, ആസ്‌ത്രേലിയ, വടക്കുപടിഞ്ഞാറന്‍ അമേരിക്ക എന്നിവിടങ്ങളില്‍ ഇതു ദൃശ്യമാവും.

courtesy : Shri.Shinod Edakkad  http://shinod.in/index.php/archives/1035