by a Thinker, Sailor, Blogger, Irreverent Guy from Madras

Showing posts with label Science-Technology. Show all posts
Showing posts with label Science-Technology. Show all posts

Spotting a Suvega Moped or a Motobécane Mobylette


Today morning while walking around in an area which I do not frequent too often, I came across some old two wheelers – motorbikes, scooters, and a moped – rusting away.  The motorbikes, scooter and scooterettes were not of much interest, as they were of fairly recent models.  They all were made during the last 20 years or so, and abandoned as their owners probably upgraded after running them down.

But what caught my attention was the old Suvega moped, the first ever moped to be manufactured in India.  From around 1965 or so till the late 80s, the Indian Suvega, the original of which is the licenced model of the popular Motobécane Mobylette of France, ruled the roost.  I rode my first every motorized two wheeler on one such Suvega in the early 80s.

And an experience never to forget.  The unique feature of those old mopeds was that you had to pedal them like a bicycle to get them started – there was no kick starter. One hot summer day, around 2 kilometres from my home, the Suvega I had gone on a joyride broke down and refused to start.  One very advertised advantage – not actually one, but probably would be of use in those days – of the Mobylette-Suvega was that you can flip a lever / remove a nut in its main drive chain, disconnect the engine and just pedal it like bicycle (being so long ago, don’t exactly remember it, but the approximate location is marked with a circle and an arrow near the pedal).

It was not true, as without a true flywheel and gear arrangement, it could not be driven as easily as a bicycle.  The intention was to flip the lever and make the Mobylette-Suvega easy to push around.  But believing that it can be pedal-driven like a bicycle, it was a huffing, puffing, sweaty, almost a breakdown incident, in that hot summer.

Not easily forgotten.  But the Mobylette-Suvega was one of the most robust, trusted moped even on Indian roads.  Till it folded down, the Mobylette-Suvega, with just a 49cc engine, used to dominate the under 50cc races at the Sholavaram race track. The advent of the TVS-50, especially the later 80s model with kick start put paid to Mobylette-Suvega in Indian roads.  But nice to see one around – that too with the round plastic holder near the front wheel where the road tax copy used to be placed (marked with a yellow circle) almost intact.

motobécane-mobylette-suvega-moped
Read More

Asteroid 2014 JO25 ‘The Rock’ safely passes Earth


The big asteroid that safely swept past Earth on Wednesday, April 19, 2017, night India time, is larger than expected as per the astronomers. The asteroid safely passed the Blue Marble at some 1,768,239 km (1,098,733 miles) distance or about 4.6 times the distance from Earth to the moon. The asteroid 2014 JO25 has been nicknamed ‘the rock’.

Astronomers with the aid of the powerful radio telescope at Arecibo, Puerto Rico,were able to ping asteroid 2014 JO25 to obtain radar images of the approaching space rock.  They found 2014 JO25 is a contact binary asteroid - two space rocks that were originally separate bodies - and each segment is about 640 meters and 670 meters (2100 to 2200 feet) to total 1.3 km approximately.  It also spins around every 3.5 hours.

The 2017 flyby is the closest by an asteroid this large since the encounter by 4179 Toutatis at 4 lunar distances in September 2004. The next known flyby by an object of comparable size will be the 800-meter-diameter asteroid 1999 AN10 approach within one lunar distance in August 2027.

So why is the asteroid 2014 JO25 nicknamed ‘the rock’?  The straight obvious connection is with Dwayne ‘The Rock’ Johnson.  But the real reason is that initially, the asteroid was described as the size of the Rock of Gibraltar. So the rock nickname stuck.  Shame since this asteroid has not come this close to earth in 400 years and will not do so until 2500 CE.

Last time we had an asteroid near miss was on 15 February 2013, when the much much smaller, 30 meter diameter 2012 DA14 whizzed by at just 30,000 km distance from earth.  Google initially released a Doodle, but withdrew it when a meteorite stuck in Russia and caused causalities on the same day.  Since there has been no such misfortune yesterday (or today), here is the Doodle, modified of course by me, for your fun.

Have a safe upcoming weekend.

asteroid-2014-JO25-the-rock-near-miss-19-apr-2017
Read More

The Crow and the DTH


The relationship between the pigeons and the statues is well known.  In fact, whenever I see statutes of leaders, which are like daffodils in spring in Madras, now Chennai, I feel both grief and glee.  Grieve to see the statue of Mahatma Gandhi, with a fair bit of ‘work’ by the pigeons.  Gleeful to see the statues of some politicians (who shall remain unnamed), and wish there were more pigeons in the area.

Where there are less pigeons, and traditionally Chennai was a pigeon free territory till 15 or 20 years ago, the crows used to fill in.  The crows are seen not as pests, but as a insect control and clean-up worker.  If not for them, the rats, the cats, and et. al, which die off on the roads would stink the town down.  There is also a tradition in some families of feeding the crows every morning with a spoonful of fresh cooked food, in memory of the ancestors.

You may wonder where this ramble about the pigeons and crows is leading to, and how it is connected with the modern DTH broadcast.  DTH is Direct-To-Home broadcast of usually TV signals from satellite, and also called satellite TV.  The terrace equipment consists of the parabolic dish antenna of around 1-1/2 feet diameter, with a contraption on a bracket at its focal point called LNB.  That contraption is a wave guide and a LNB (Low Noise Block downconverter) and the waveguide side which faces the dish has a plastic like cap of special material.

My DTH installation is around 10 years old.  After cyclone Vardah in December 2016, me and my bro found a wooden twig which had pierced the cap leaving a hole of 1 inch or so.  We removed the twig and did not cover the hole, and there has been no problems till now.

Yesterday early morning, my mom switched on the TV and found that there was no reception.  Surprised, I checked up the connections which were all OK, including a cursory inspection of the dish antenna, and raised a complaint with the service provider.

After brunch, once again, I investigated the antenna.  And the culprit was a Crow.  A neighbour is in the habit of feeding the crows early in the morning around six.  He usually scatters bits of bread, biscuits, wafers, savouries, or whatever is in hand.  Yesterday, he had scattered a savoury called ‘Ribbon Pakoda’ – a rice & gram flour fry shaped like a ribbon.

A crow had taken a piece of that ribbon pakoda and stuffed it into the hole in the LNB assembly.  Whether it got stuck there, or the crow had stuffed it there deliberately for later retrieval is not known.  But that ribbon pakoda made my mom’s life miserable for about 6 hours, disrupting the DTH TV.  Here is the image of the ribbon pakoda, partially out from the hole in the LNB.  I removed it, and made my mom happy.

crow-dth-ribbon-pakoda

BTW, the technician did turn up today, and after seeing the condition of the old LNB, I had it replaced with a new one.
Read More

Supermoon at Chennai 14 Nov 2016


Finally, the clouds seemed to part, and I could get an actual sight of the Supermoon of 14 Nov 2016 from my rooftop.  Has been a long wait as it appears that my part of Chennai was attracting a lot of clouds, and a bit of drizzle too.

It is called Supermoon because this full moon occurs when the Moon is at its perigee – the closest point of approach to Earth.  This Supermoon is special as the lone natural satellite has not been this close to Earth since 1948, and will not be so close till 25 Nov 2034.

If you had missed it, and are feeling a little down, don’t be.  Supermoon occurs at least once every year, and sometimes more, like this year’s October, November, and December full moons.  As everything else, this 1948–2016-2034, is also much media hype in the internet age.

For example, the last such ‘near-closest’ Supermoon was on March 2011.  And the Supermoon of today is ‘bigger’ because the Moon is closer to Earth today, by, about 68 km (41 miles or 0,02%), Yes, it is only about 0,02% nearer, bigger, and brighter than that of March 2011, and you eyes will not be able to tell the difference.

So, why am I writing about this Supermoon hype?  Because I like looking up at the sky in night time or early morning, and try to remember all the stars and patterns learned during my sailing days.  For example today, after a look at the moon, I turned my head to look at Orion the Hunter, also emerging from the clouds

supermoon-chennai-14-nov-2016

Tags: ,
Read More

India launches GSLV F05 with indigenous cryogenic engine


At 16:50 IST today, 08 September 2016, India successfully launched the 1st operational flight of the GSLV Mk2 rocket, with an indigenous cryogenic engine, deploying a 2200 kg INSAT 3DR satellite as payload  The cryogenic’ tag comes from the fact that hydrogen and oxygen are both cooled to cryogenic or ‘very low’ temperatures so that they become liquids and start flowing as gas, once the engine is ignited.

To understand what is cryogenic, imagine it as the standard kitchen LPG gas cylinder – the ‘Liquefied Petroleum Gas’ or LPG is actually stored as a liquid, till it starts flowing up into the gas stove or range as a gas to cook the food.  In the GSLV cryogenic stage, they help propel the rocket and its payload.

Why is cryogenic important?  To put it simply, rocket fuels are stored as solid or liquid..  The solid fuel in a rocket – think of your Deepavali rocket – is easy to manufacture, store, move and fire quickly.  The fuel does not flow, but is easier to manufacture, store, and manage.  Liquid fuels do flow, and release more energy, but are difficult to store, and the storage/engine technology itself is very difficult to master.

But for a nation with hopes in space flight, and manned missions, mastering liquid fuel technology is essential – for the simple reason that liquid fuel rockets – from huge Saturn 5, Ariane 5/6, Chang Zheng (Long March) 7, GSLV Mk 2/3 to small thrusters on astronaut space suits for Extra Vehicular Activity (EVA) – can be switched on and off and on again.  This switch on-off-on function cannot be done with solid fuels.

Thus, unless a nation masters cryogenic engine technology, it cannot hope to venture ‘where no human has gone before’.

So, here is the snapshot of the spectacular launch of the GSLV Mk 2 F05 carrying the 2.2 ton INSAT 3DR satellite as its payload.

gslv-f05-insat-3dr-launch-08-sep-2016-isro

Tags: , ,
Read More

Four more Boeing Poseidon 8I Neptune for India


So, the Narendra Modi regime has gone ahead, and meekly followed the earlier proposal to acquire 4 more Boeing Poseidon 8I Neptune by the earlier UPA government.  With this almost all of the major proposals and decisions of the earlier Congress led UPA administration has been humbly accepted by the Narendra Modi led BJP regime.

Whether it was the ramming of Aadhaar implementation in the name of cutting subsidies (or as the earlier Congress administration termed it as ‘targeted subsidy regime’), the GST Bill, continuation of the Land Bill 2013, or any other major policy implementation.

Not only simply following the Congress planned footsteps, this Narendra Modi led BJP regime has even more blindly held on to some serious lack of judgement policies of the erstwhile administration.  Whether it is in the National Judicial Appointments Commission, opposing the smooth functioning BCCI, Jallikattu Ban, this regime even appeared before the highest judiciary parroting the same principles, and got slammed by the courts.

OTOH, whether it is the implementation of One Rank One Pension (OROP) in Defence Personnel, GAIL pipeline through agricultural lands of Tamil Nadu, Methane Gas Extraction in prime agricultural lands, inability to clamp down terrorism, or impotence against Maoists, it is even worse off.  So much for the party with the difference.

But for the moment, let us marvel at one of the excellent Anti Submarine & Anti Surface Warfare, Ship Interdiction and Electronic Signals Intelligence (ELINT) platform – the Poseidon 8I Neptune from Boeing.  Built on the proven 737-800 airframe with 737-900 wings, they will replace the Indian Navy’s ageing eight Tupolev Tu-142 ‘Bear’ & five Ilyushin Il-38 ‘Dolphin’ being used as ASW & ELINT platforms.

An interesting side note is the Poseidon 8I Neptune for Indian Navy will carry the Magnetic Anomaly Detector (MAD) which were questionably deleted by the US Navy.  In addition the Indian Poseidon 8I Neptune will also carry an OceanEye Aft Radar.

Here is a composite of the Boeing Poseidon 8i Neptune cutaway with approximate locations of equipment on board.  All the information are compiled from Public Domain Information in various websites.  The original Poseidon 8A image is from the Boeing Website.

Boeing-Poseidon-8I
Read More

Solar Impulse 2 Full Flight Path Google Maps


Solar Impulse 2, the first fully solar-powered aeroplane, has completed the first round-the-world flight, after touching down in Abu Dhabi early on Tuesday, 26 Jul 2016.

The plane, with a wingspan wider than a Boeing 747 and carries more than 17,000 solar cells on its wings, began the circumnavigation on 09 Mar 2015 in Abu Dhabi. It has since crossed both the Pacific and Atlantic Oceans using no fossil fuel and has spent 21 days in the air, chalking up a total of 43,109 km.

The aim of the Solar Impulse 2 adventure was not to demonstrate solar-powered planes for widespread use, but was more humble – to publicize the capabilities of renewable energy.

Piloted in turn by Bertrand Piccard and Andre Borschberg, the Solar Impulse 2 is not much heavier than a car, but has the wingspan of a Boeing 747, and has a cockpit just about the size of a public telephone booth (do you even remember one?), with the pilots forced to wear oxygen tanks to breathe at high altitude and can sleep only for 20 minutes at a time.

But even with all these difficulties, some 19 Aviation World Records were broken/set - flight from Nagoya in Japan to Hawaii, US, lasted nearly 118 hours, with Borschberg breaking the record for longest (time duration) uninterrupted solo flight.

The tactic was to climb to higher altitude, as required or modelled for the leg, during day time when the solar cells are getting charged, and glide down slowly during the nights when the cells are not being charged.  As can be seen in the Google Maps, the maximum altitudes of around 8400 - 8600 metres were attained during the long legs of 2 days or more.

The obvious question is why not climb even more higher, and why stop at around 8500 m (~27,800 ft)? Why not climb to 35,000 ft (~10650 m) like airplanes do, and glide even further?

The answer is the cabin is not pressurized, the temperature drop would be excessive (-65F / -53C), and the pilot had to resort to oxygen bottles to breath above 8000 m - the much ill famed 'death zone' in mountain climbing.  A point to remember is skydivers making jumps from 15,000 ft (~4500 m) are required to carry oxygen on the way up, and above 23,000 ft (~7000 m) are required to carry oxygen both up and diving down.  That's the reason Solar Impulse 2 kept to around 8600 m maximum altitude.

What about future? Personally I think it would be wonderful if Solar Impulse 3 attempts a similar circumnavigation in 8 legs, instead of 17, in 8 weeks.  Take off from Abu Dhabi - Kolkata - Nanjing or Shanghai - Hawaii - California - Pennsylvania or New York or Boston - Seville - Cairo - Abu Dhabi.

So here is the full Flight Path (simplified) of Solar Impulse 2 in Google Maps, giving the details of airports landed, legs travelled, with distance, time, and maximum altitude attained during that leg.



Picture for pinning

solar-impulse-2-flight-path-full-google-maps
Read More

South African super-telescope reveals distant galaxies and black holes



Read more at the link http://bit.ly/29LO0eq
Read More

#MeerKAT SKA Radio Telescope reveals 1300 galaxies where we saw only 70 http://bit.ly/29NjgNt



Read More

Our nine-point guide to spotting a dodgy statistic



Read more at the link http://bit.ly/29Scwy0
Read More

#Juno at Jupiter http://bit.ly/29kJMfx



Read More

PSLV C29 Launch Video with Event Explanation


India's ISRO launched the Polar Satellite Launch Vehicle (PSLV) on its 29th Commercial mission (C29) carrying six satellites from Singapore.  What a launch.  Saw the 1st Stage Separation, 2nd Stage Ignition, Heat Shield Separation, and the 3rd Stage firing from my rooftop.

Henceforth, I would request ISRO to launch all the rockets in early evening or night.  What a beautiful sight.

For those who missed it, here is the video.


Tags: ,

And an image for Pinning:


Read More

Undersea Internet Network


#internet cable network
Read more at the link http://wapo.st/1N4h1CW
Read More

What is a Stellarator


#Wendelstein7X #stellarator tagged by www.madrasnow.com
Read more at the link http://bit.ly/1PKypx7
Read More

Astrosat is not India’s Hubble


Of late it has become the habit of chauvinistic, if not jingoistic, Indian netizens to compare whatever ISRO does with that of NASA, and falsely claim that we have bettered NASA (or others).  We saw many of those silly tweets when India’s own Mars Orbiter Mission (MOM) was launched at the same time as NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft.

The immediate comparison was how cheap MOM was (~$78 million) versus MAVEN (~$671 million).  It was conveniently brushed over that MAVEN is more than four times bigger at 65 kg versus the 15 kg Mangalyaan, apart from other technical capabilities.  While India did good, we have a long haul ahead to catch up with the Americans.

With today’s launch of the first dedicated Astronomical observation satellite Astrosat by ISRO, the gung-ho crowd is sure to go about how the “India’s own Hubble” cost a mere Rs. 178 Crores (~$27 million) while the famed HST burned a $2.5 billion hole.  Once again let us just compare their weight, keeping the technology and its maturity out of it.

The Astrosat weighs around 1500 kg, whereas the Hubble Space Telescope is a behemoth at 11,110 kg – the heaviest satellite ever launched till date.

In this respect, it was interesting to listen to Dr. Kasturirangan, former Director, ISRO, during his post-launch speech.  He said something like, ‘when we planned the Astrosat about 10 years ago, the thinking was it should be up and flying in 8 to 10 years, as otherwise ISRO will be beaten by competitors.  But I am happy to say that no one in the world has plans for a similar craft till date.'

I guess the good doctor does not consider NASA and James Webb Telescope (JWT) as competitors, as he knows the technology gap between India  and the USA.

That is how scientists think and work - within the resources, prioritizing the requirements, planning ahead - for their successors to carry on, reap the benefits, and build on.  Hats off to them.  Great work ISRO.

But there is one area where Indians are as good as the Americans – photoshopping.  So here is my one up on the original NASA image, with the insertion of Astrosat.  Have fun.

observatories-across-spectrum-with-astrosat
Read More

Performance management and the bell curve


Typical real life #BellCurve tagged by www.madmadrasi.net
Read more at the link http://j.mp/1KDkV2Y
Read More

Infosys Says Goodbye To Bell Curve Appraisal...


Poor understanding of #BellCurve tagged by www.madmadrasi.net
Read more at the link http://j.mp/1KDkMfK
Read More

The Universe is slowly dying


Can #entropy be reversed #Isaac Asimov's short story The Last Question seems to be true
Read more at the link http://j.mp/1J1ghfx
Read More

Why an iron fish can make you stronger


Cooking an Iron Fish to cure Anaemia tagged by www.madmadrasi.net
Read more at the link http://j.mp/1EPG6IV
Read More

Watch PSLV C27 launch with IRNSS-1D


India on Saturday, 28 Mar 2015, moved one significant step closer to its  ambition to establish an independent regional navigation satellite system, as ISRO’s PSLV C-27 successfully launched Indian Regional Navigation Satellite System (IRNSS) 1-D satellite into the intended orbit.

While the existing GPS belonging to the USA is global, the IRNSS is more modest, with the aim limited to provide a precision positioning system for the South Asian region.  IRNSS 1-D is the fourth of the series of seven satellites, which would form ISRO’s IRNSS.

Here is the video of the launch of the PSLV C27 from my rooftop at Chennai.

Read More

Support - Donate

Your Blog is

Donate thro ECWID

Contact Form