Cover Story

Aurora: The celestial light curtains

From the News Desk Latest Updates on

UNIVERSE IN THE SCHOOL

SPACE EVENTS

Astroinquisites

Did men really land on the moon?

Astronomy at HomeShadow Dance

BLOGPOST

James Webb Space Telescope –

An inside look

SPACE NEWS

APRIL’14

Monthly Newsletter of SPACE Group

Chief Editor : Sachin BahmbaEditors: Amit Verma &

Naitik Saroha

Guest Article

Equinox or Equilux? That’s the Big Q.

By C B DevgunAstrophotography

INDEXS No Topic Page No.

1 Universe In The School News 3

2 Blog : James Webb Space Telescope – An inside look 6

3 Events News 9

4 Astrophotography 13

5 Sky this month 17

6 School In Focus 19

7 Cover Story: Aurora: The celestial light curtains 22

8 Astroinquisites: Did men really land on the moon? 25

9 Guest Article: Equinox or Equilux? That’s the Big Q. By C B Devgun, President, SPACE

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10 Astronomy at Home : Shadow Dance 28

11 Astrotourism – Bonjour!!!! 32

12 Astroport – Sariska 33

13 SPACE is Hiring – Apply Now! 34

UNIVERSE IN THE SCHOOL NEWS

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CENTRE FOR STUDENT EXCELLENCE PROGRAMME

Students and SPACE Educator during the solar observation

Students participating in ‘balloon car’ activity

Student volunteer and Educator demonstrating the working of ‘Hover Craft’

National Science Day at Step By Step, Noida on 4th March, 2014

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SPACE EXPLORERS WORKSHOPSSPACE conducted a wide variety of hands-on fun astronomy workshops at various schools in Delhi:

Students learning the construction of rockets

2. Rocket - A space vehicle workshop at Amity International School on 24th February, 2014

Students making their own rockets

1. Air Rocketry workshops at Bluebells International School on 7th March, 2014

Students learning about the launch mechanism

Students learn about air pressure Students make their own rockets and get ready for launch

Students launch their rocket and Winners of the competition

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SPACE EXPLORERS

To Have Fun With Astronomy & For UITS Updates

3. Astronomy Day at SUNCITY SCHOOL on 28th February, 2014

4. Astronomy Day at DPS International, Saket on 24th February, 2014

5. Astronomy Day at Srijan School on 26th February, 2014

Students showing how a comet is made

Students learning the utility of astronomy tools provided to them in their kit

Students observing the sun through Pinhole Projector

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BLOG JAMES WEBB SPACE TELESCOPE – AN INSIDE LOOK

Telescopes in space are the next big thing in the field of astronomy to get unresolved answers about our mystical universe. In 1946, Lyman Spitzer, a professor and researcher at Yale University, argued that a space telescope would offer great advantages over ground-based observatories. His paper, “Astronomical Advantages of an Extra-Terrestrial Observatory”, explained that the Earth's atmosphere blurs and distorts light coming from stars. Even the most precise and advanced telescopes on the ground cannot escape this phenomenon, but a telescope in orbit can. Furthermore, the atmosphere blocks X-rays emitted from high-temperature phenomena in stars and other objects, so they cannot be detected by instruments on the Earth's surface. A space telescope would also allow scientists to accurately measure these emissions as well.

After many discussion and meetings, almost after half a decade the first space telescope was successfully placed in orbit in 1990, the famous Hubble Space Telescope. It will be soon replaced by its successor, James Webb Space Telescope (JWST), yet another achievement in this field.

JSWT, originated as the Next Generation Space Telescope (NGST) in 1996, based on generic planning for Hubble successor in 1993. It was renamed in 2002 after NASA's second administrator James E. Webb (1906–1992), noted for his role in the Apollo programme and establishing scientific research as a core NASA activity.Address in SpaceJSWT will not orbit the Earth, instead it will sit at the Earth-sun L2 Lagrange point, 1.5 million km away! As Hubble is in Earth’s orbit, it could be launched into space by the space shuttle. Webb will be launched on an Ariane 5 rocket and because it won't be in the Earth’s orbit, it is not designed to be serviced by the shuttle.

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At the L2 point Webb's solar shield will block the light from the sun, Earth, and Moon. This will help Webb stay cool, which is very important for an infrared telescope.

Goals of JWSTThe James Webb Space Telescope will be a giant leap forward in our quest to understand the Universe and our origins. The Webb will examine every phase of cosmic history: from the first luminous glows after the Big Bang to the formation of galaxies, stars, and planets to the evolution of our own solar system. The science goals for the Webb can be grouped into four themes:

Contd.

The End of the Dark Ages: First Light and Re-ionization seeks to identify the first bright objects that formed in the early Universe, and follow the ionization history. Assembly of Galaxies will determine how galaxies and dark matter, including gas, stars, metals, physical structures (like spiral arms) and active nuclei evolved to the present day. The Birth of Stars and Protoplanetary Systems focuses on birth and early development of stars and formation ofplanets. Planetary Systems and the Origins of Life studies the physical and chemical properties of solar systems (including our own) and where the building blocks of life may be present.

Instruments to achieve these goals JSWT will observe primarily in the infrared and will have four science instruments to capture images and spectra of astronomical objects. These instruments will provide wavelength coverage from 0.6 to 28 micrometers (or "microns"; 1 micron is 1.0 x 10-6 metres).

JSWT will have a 6.5 metre diameter primary mirror, which would give it a much larger collecting area than the mirrors available on the current generation of space telescopes. Hubble's mirror is smaller with 2.4 metres in diameter and its collecting area is 4.5 m2, giving Webb around 7 times more collecting area.

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The infrared part of the electromagnetic spectrum goes from about 0.75 microns to a few hundred microns. This means that Webb's instruments will work primarily in the infrared range of the electromagnetic spectrum, with some capability in the visible range (in particular in the red and up to the yellow part of the visible spectrum).The instruments on Hubble can observe a small portion of the infrared spectrum from 0.8 to 2.5 microns, but its primary capabilities are in the ultra-violet and visible parts of the spectrum from 0.1 to 0.8 microns.

Why are infrared observations important to astronomy? Stars and planets that have just begun to form lie hidden behind cocoons of dust that absorb visible light. (The same is true for the centre of our galaxy.) However, infrared light emitted by these regions can reveal what is inside.

Contd.

Hubble is 13.2 meters (43.5 ft.) long and its maximum diameter is 4.2 meters (14 ft.) It is about the size of a large tractor-trailer truck.

By contrast, Webb's sunshield is about 22 meters by 12 meters (69.5 ft x 46.5 ft). It's almost as big as a Boeing 737 airplane!

How different it is?

The full-scale model is assembled on the lawn at Goddard Space Flight Center, and displayed during September 19 - 25 2005. The Webb Telescope team took a group photo with it. Seeing the people gathered next to it shows its scale nicely.

By Neeraj Ladia

EVENTS NEWS

PAST EVENT

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For other upcoming celestial occurrences

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SPACE CALENDAR

SPACE Foundation

SPACE Foundation with The Russian Centre of Science and Culture co-organised the 80 th birth anniversary of Yuri Gagarin (the first human to journey into outer space) and the 30 th anniversary of Russian- Indian joint space flight on 19th March’14 at The Russian Centre of Science and Culture, Feroze Shah Road, New Delhi. The event started with the lighting of Lamp by the distinguished guests of the evening, followed by a briefing on the event by Miss Anastasia V. Khokhlova, Head of Cultural and Information department at The Russian Centre of Science and Culture. In this connection a photo exhibition was inaugurated – “Yuri Gagarin- the first planet cosmonaut”. Later on various speakers expressed their views on the occasion. SPACE Foundation President, Mr. C B Devgun shared his experience on SPACE initiative of Eclipse Chasing in Novosivirsk, the capital of Siberia and said that, as human being started venturing into space, we moved towards the advancement of Technology. He further talked about the achievements made by Yuri Gagarin, the 1st Indo-Russian space flight, and Rakesh Sharma, the first Indian to travel in space and in 1 st Indian space flight and India space programme.

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EVENTS NEWS

SPACE Technology & Education Pvt Ltd`

SPACE celebrated vernal equinox with students by measuring the Earth’s circumference at Jantar Mantar on 20th March, 2014

On 20th March, 2014, SPACE celebrated vernal equinox by measuring the circumference of the Earth, using Eratosthenes experiment, with its associated students and conducting a walk at Jantar Mantar.

About 55 school students from class VI to VIII participated. 11 schools from Delhi & NCR participated, including Bal Bharti Public School - Rajendra Nagar, Indraprastha International School - Dwarka, GD Goenka Public School-Rohini, Sachdeva Public school - Rohini, Amity International School – Pushp Vihar, Gurgaon, Noida, Saket and Vasundhara, Chinmaya Vidyalaya – Vasant Vihar, Navy Children School – Chanakyapuri. Most of the participating schools achieved more than 90% accuracy in their results.

This year, SPACE also participated in an international activity – ‘The Eratosthenes Experiment 2014’ which is organized in the framework of the Open Discovery Space Project, an educational outreach programme based in Europe. Under this, students from schools across the world measured the Earth’s circumference by performing the experiment of Eratosthenes. They partnered with cities along the same longitude, shared the data and made the calculation jointly with those cities. 

With the help of experts at SPACE the students replicated this experiment wherein they used the shadows cast by the sun to calculate the circumference. The participants were also taken on a guided walk around Jantar Mantar where they learnt about the usage of the ancient instruments.

Ms. V. R. Geetha, a student co-ordinator from Bal Bharti Public School, Rajendra Nagar said, “Session was well conducted by SPACE group members. The working of various yantras was well explained by SPACE educators. This is nice way to popularize hands-on science and promote learning in an informal atmosphere as a group activity. “

PAST EVENT – Project ParidhiSPACE Educator Abhinav explaining the Eratosthenes experiment to the students at Jantar Mantar. Click here for more photos.

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During the month of April, SPACE will be celebrating Global Astronomy Month 2014 (GAM) with its client schools. Organized by Astronomers Without Borders (AWB) every year, GAM is the world's largest global celebration of astronomy. It brings new opportunities, and brings enthusiasts together worldwide, celebrating AWB’s motto, One People, One Sky. 

CURRENT EVENT

Out of the gamut of activities that AWB proposes this year, we have selected six activities for our client schools. The activity reports sent by schools to us will be further sent to GAM/AWB. The activities suggested by SPACE are:

Solar Observation - April 25th Mars Observation - 11th April Vesta Watch - 10th April International Earth and Sky Photo Contest - 10th March to 24th April Globe at Night – 20th to 29th AprilAstropoetry Contest - 1 st April to 1st May

This year we are also celebrating the 30th anniversary of the first flight of an Indian into space. On 2nd April, 1984, Rakesh Sharma became the first Indian cosmonaut to venture into space, as part of the a joint programme between Indian Space Research Organisation (ISRO) and the Soviet Intercosmos Space programme.

To commemorate this achievement, SPACE invites messages from its associated teachers and students for Rakesh Sharma, ISRO, Sonia Gandhi and the Russian Ambassador to India. The best messages would be selected by us and presented along with the name of the sender to the intended audience.

To leave your messages, please visit the link: Message FormFor more details, visit http://space-india.com/gam.html

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UPCOMING EVENTS

All India Asteroid Search Campaign - 2014 will be organized by SPACE for its associated students in April. It is proud to be able to bring this campaign to the Indian students for the fifth time consecutively.

The campaign is conducted in collaboration with International Astronomical Search Collaboration (IASC, Hardin-Simmons University, Texas, USA). SPACE is the coordinator for this highly recognized programme in India. 

Under this project, the University offers the participants exclusive access to images taken by 24” telescope and 32” telescope positioned in Astronomical Research Institute (ARI) Observatory, USA. Participants then download these images and analyze the data with specialized software provided during training to search for asteroids. Objects reported by students could be potential discoveries. All observations contribute to the Near Earth Object (NEO) data compiled by NASA and Jet Propulsion Laboratory (JPL). 

The campaign begins on 29th April. For details, visit http://space-india.com/aiasc.html

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Astrophotography is a specialized type of photography that entails recording images of astronomical objects and large areas of the night sky.

A S T R O P H O T O G R A P H Y

PHOTO 1 :  ORION NEBULA IN H ALPHA FILTERBy C B Devgun, President, SPACE

Description:Imaging through hydrogen alpha filters can bring remarkable enhancement to objects in the hydrogen-alpha line. Most of the gas in space is made of hydrogen. When the hot, energetic, ultra-violet light from young stars hits the hydrogen atoms, it strips off electrons. This forms a plasma that glows and emits light as the electrons and atoms recombine and give off light at particular, specific wavelengths. The visible portion of the electromagnetic spectrum ranges from approximately 400 nm to 700 nm. The strongest emission wavelength in a hydrogen nebula is in the deep red part of the spectrum known as the hydrogen-alpha line.

Location: Mayhill, New Mexico (Remote Observatory)

Instruments Used:Camera: SBIG STL-11000M with H-alpha filterLens/Telescope:  0.10-m f/5.0 astrograph (T14 iTelescope) Specifications: Focal Length: 530mmExposure Time: 300 sec * 4Aperture: f/5.0Processing Software Used: MaxIm DL, Adobe Photoshop

PHOTO 2 :  A NIGHT AT WORKBy Rishabh Jain, Educator, SPACE

Description

Students ( near Bonfire ) and Educators rewind after an overnight observation during the Messier Marathon weekend. The summer arm of the Milkyway Galaxy can be seen above the bonfire.

Camera: Canon 6D Lens: Tokina 11-16/2.8 Specifications: Focal Length: 16mmSensitivity (ISO): 5000Exposure Time: 30 sec.Aperture: f/4Processing Software Used: DPP, Adobe LR and PS

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Description:Sun rising on the day vernal (spring) equinox!!!Instrument Used ( issued from SPACE )Camera: Canon 1100D Lens:  EFS 18-55

Specifications:

Focal Length: 55Sensitivity (ISO): 200Exposure Time: 1/200 sec.Aperture: f/10Processing Software Used: Adobe Photoshop CS6

PHOTO 3 : SUN RISING ON THE VERNAL (SPRING) EQUINOX!!!By Neeraj Ladia, Educator, SPACE

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Photo 4: A FOALABy Aanchal Tandon, Educator, SPACE

*Astroport is SPACE's new sky observation facility cum research centre at Sariska, Rajasthan, India

Description:Andromeda Galaxy -  Our galactic neighbor is a spiral galaxy approximately 2.5 million light-years (24000000000000000000kms) from Earth in the Andromeda constellation. It contains One TRILLION (1012) stars, at least twice the number of stars in the Milky Way galaxy.This is the farthest object that we can see with unaided eyes. About 5 billion years from now, our home galaxy – The Milkyway and the Andromeda Galaxy will merge to form a newer bigger galaxy.

Instrument Used:  Camera body: stCanon 1100D (Issued from SPACE )Lens:  50mm/1.8 ( borrowed from Rishabh Jain | SPACE)

Location: Astroport, Rajasthan

Specifications: Focal Length:  50mm  Sensitivity:  ISO 800Exposure: 6 sec * 50Stacking software used: DSSProcessing software used: Adobe PS

SKY THIS MONTH Stay updated about the events of the sky this month

Constellations

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Evening ( Dusk )North - Cassiopeia, Ursa Major, Ursa MinorEast - Leo, Bootes, Corvus, CraterWest - Aries, Perseus, Taurus, Auriga, GeminiSouth - Canis Major, Zenith - Cancer

Midnight North - Ursa Minor , Ursa MajorEast -  Lyra, Corona Borealis, Bootes, HerculesWest -  Cancer, Leo, GeminiSouth - Libra, Corvus, Crater, VirgoZenith - Leo, Cancer

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Constellations

Morning ( Dawn )

North - Ursa Minor, Ursa Major, Cepheus, Cassiopeia

East - Cygnus, Pegasus, Capricornus

West -  Bootes, Virgo, Corona Borealis

South - Scorpius, Saggitarius

Zenith - Hercules, Lyra

Moon Phases, April 2014

Last Quarter –  April 3, 4:36

New Moon – April 10, 9:35

First Quarter – April 18, 12:31

Full Moon – April 25, 19:57

All timings follow Universal Time (UT) standard

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SCHOOL IN FOCUS

Sachdeva Public School, Rohini

Sachdeva Public School, Rohini established in April 1992 is a recognized School affiliated to C.B.S.E., governed by the rules, regulations and curriculum of C.B.S.E. and is run under the aegis of the “Shri Laxman Dass Sachdeva Memorial Educational Society(Regd.)”  Under the brilliant guidance of Chairman Sh. S.K. Sachdeva, the school aims to achieve to perfection its fundamental motive of moulding the growing generation of the nation, through impeccable training in education, as well as environment. Principal, Dr. (Mrs) Ravija Prakash aptly summarizes the futuristic vision of the school through her message to the students and parents,” We have stepped into a world where the horizons are unlimited. At one end of the spectrum is nano technology where the entire communication system proposes to be of the size of an air molecule; and at the other are the new frontiers vanquished in space travel.”SPACE has been associated with Sachdeva Public School since 2008 and has had a very good astronomical relationship. The students have always shown a lot of interest and enthusiasm and have even pursued the subject till Module-3.

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“The exploration of the cosmos is a voyage of self discovery”.  The universe has infinite horizons and a journey into space, opens unending marvel for students to unlock some of its greatest secrets.Milky way is quite fascinating and its incredible mysteries are yet to be unravelled. I hope that the journey of our students into these realms will provide the budding astronomers with an insight into the vast field that is astronomy.

Message from the Director, Sachdeva Public School, Rohini

Messages from Club Coordinators

“It is astonishing how short a time it takes for something wonderful to happen”.  In our universe, a plethora of enthralling events are occurring some of which are being taught to our students in the Astronomy Club.

It is just the start of a never ending study of this enigmatic universe.

“The study of Astronomy compels the soul to look upwards and lead us from this world to another.”  Exploring the outer realms of the vast universe is like hurling oneself into the undiscovered.  This club has provided the students a true manifestation of the mystical world.

Ms. Aditi Sen Gupta Ms. Manisha Shokeen

Director, Mr. Sanjay Sachdeva

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Students with Club Coordinators at Jantar Mantar for Project Paridhi on 20th March,2014

Students showing the comet made by them in Comet making club session

SPACE Educator guiding the students to perform the experiment

Students viewing sun through pin hole projector made by them

Students showing their elation after receiving the Astronomy Club Kit

Telescopic observation by students and teachers during Evening Observation session in school

COVER STORY

Aurora: The celestial light curtains

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After having been associated with over 70 schools in our long journey of popularizing science and Astronomy, we thought of getting in touch with some of our students and asking them how Astronomy and SPACE have impacted their lives. This is what one of them, Ambar Prasad, Class XII of Amity International School, Noida, had to say.

ICELANDMy family planned to visit Iceland in late 2009 after my Astronomy teacher told me about the incoming Coronal Mass Ejection and the effect it would have on the Aurora Borealis. And, in March 2012, we landed at Reykjavik Airport, Iceland. The solar activity was predicted to be ideal. Highly optimistic, all of us, my father, mother, brother and I, drove around the empty roads of this tiny island nation, looking for anything that resembled bright green lights. Clouds, the greatest enemy of a star gazer, soon struck. We would get excited at any sign of a luminous haze, but which turned out to be mostly city light pollution.

On the eighth night, with the weather on our side, I finally noticed a faint haze. I went out with my tripod and camera, thinking that in real life the photos were a result of trick photography. We were heading back, everyone half asleep, except for my father who was on the wheels. My brother pointed two mongooses running across the road and my mother turned back to try and spot them. All of a sudden, she screamed and the car screeched to a halt. Behind us, going unnoticed, was the greatest light show on the Earth.

Bright green columns of light emerged from the clear, dark sky. The green flowing light curtains illuminated the entire snowy landscape. The Arctic winds were blowing fast enough to shake our car. Soon I found my tripod in mid air, flying away from me; I caught it a few metres away. After a few photos, we couldn’t stay outside and retreated to the car.

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Contd.

NORWAY

In the October of 2013, my parents decided that they hadn’t seen enough of the Aurora just yet. With the end of the 11-year solar cycle, March 2014 was our last chance. Early that month we landed in Tromso. This time we were prepared with a better camera, heavier tripod, better equipment and our eyes knew what they had to look for.

Our best chance was on the night we landed, equipped with coffee to counter the jet lag, we had planned to stay up all night. Clear skies, again, was scarce but, I pointed out the famous Orion to my father, who made me turn my head to see a bright green Aurora in the sky. In the middle of the runway, I started to take photos, and just gazed at the lights. If we could see it from a brightly lit airport over one of the biggest cities in the north, we’ll see it everywhere. We were wrong.So we drove out. Clouds had filled up the sky, with few clear patches. And just like in Iceland, we’d left the camera in the hotel. Only this time we didn’t see any activity that night.

During the last few nights that we were there, the weather worsened. We drove out in a blizzard, countering heavy snow and rainfall. The solar activity had decreased, with the band of the Aurora barely in the range of Tromso and then gone completely, contrary to the prediction.

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On our last day, we drove up to a lake in Sweden, as the weather conditions were supposed to be more favourable than in Tromso. We started to drive out at 11 in the morning, in a four-hour drive. My brother had an early flight the next morning, so we knew that we would have to drive all night back. We reached the lake early in the evening. The weather didn’t seem all that better with as much the cloud cover as in Tromso. We left from the lake, onwards to a city with better conditions. On our way, it started snowing heavily, and then, suddenly, the sky became crystal clear. The moon light reflecting off the snow filled the landscape. A few kilometres ahead, the blizzard started again. Conditions in the city became terrible. We all headed back, disappointed.

We reached that clear spot again, but the solar activity wasn’t on our side. I took a few photos of the landscape so that I don’t go home empty-handed. We were out of time, and I went out to pack up my camera, when my mom pointed out a very distinct green haze. I screamed with joy when I saw the preview, a bright green band among the clouds. It was a very dull and faint Aurora, but the photos came out great anyway. And, as a proof that all Aurora is accompanied with a wild animal, we spotted a wild reindeer grazing across the road. After taking a bunch of photos till the Aurora died, we headed back. This spot, with the clear sky is called a ‘Blue Hole’. It was surrounded by heavy snowfall.

We got back to Tromso in the nick of time, after driving all night through a horrific blizzard, high on coffee and energy drinks. My brother caught his flight, and I went back to the hotel, and slept all day.

Contributions from the Prasad family and SPACE Educator, Rishabh JainPhoto courtesy: Prasad family

Watch out for our next issue to know how to best plan your trip for an Aurora sighting!

Contd.

ASTROINQUISITES

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Over the several decades, the moon landing has always been an object of scrutiny.  Some have implied that it would have been physically and technologically impossible to land men on the moon and return them home. So was it all a hoax, after all?One of the questions raised by conspiracy theorists was that why there are no stars in the photos taken on the moon? Apparently there is considerable amount of sunlight reflecting off the lunar surface. So, in order to take crisp pictures, the camera is needed to be set at a small aperture setting, so it cannot gather enough light from the stars to be seen.

Why Is the American Flag waving even in the absence of air on the moon? Due to the design of the flag, it has rigid, extendable support pieces on the top and bottom so that the flag would look taut.The flag when being installed, was unfurled and started swinging like a pendulum due its rigid structure. This is possible both in presence or absence of air.

Why do the shadows point in different directions? Well, the shadows points in the same direction when they are at the same level and in uniformly grey terrain of the moon; it is sometimes difficult to distinguish changes in elevation.

Also, why Is there no visible flame from the rocket? Simple. The type of fuel that was used (a mixture of hydrazine and dinitrogen tetroxide) mixes together and ignites instantly, producing a "flame" that is transparent.

Did men really land on the moon?

GUEST ARTICLE Equinox or Equilux that’s the big Q.

By CB Devgun, President, SPACE

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An equinox occurs twice a year (around 20 March and 22 September), when the tilt of the Earth's axis is inclined neither away from nor towards the sun, the center of the sun being in the same plane as the Earth's equator. The term equinox can also be used in a broader sense, meaning the date when such a passage happens. The name "equinox" is derived from the Latin aequus (equal) and nox (night), because around the equinox, night and day are about equal length......... Well almost equal but not equal and that’s the catch!!!

We all have been told and taught about this in our geography lessons but never dared to question the simple fact presented to us. Let’s find out what exactly happens on equinox day and whether its equal day and night or what?

This year’s equinox day (20th March) will have sunrise at 06:26 IST and sunset at 18:32 IST - so it’s not equal day and night.

The moment of the equinox is defined as the point at which the centre of the sun’s disk crosses an imaginary line in the sky called the celestial equator, the projection of the Earth’s equator out into space.

The sun (and the Moon and all the planets) move along a line in the sky called the ecliptic, the projection of the disk of the solar system out into space. These two lines, the equator and the ecliptic, circle the sky, and because the Earth’s axis is tilted at around 23.5 degrees the angle between the equator and the ecliptic is 23.5 degrees, and the two circles meet at only two points, called equinoctial points.

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Contd.

Over the course of the year the sun, as seen from Earth, appears to make one complete circuit around the ecliptic, as the Earth in fact orbits the sun. And so on two days each year the sun’s path crosses the equator. This means a number of things:

1. that an observer at the equator will see the sun directly overhead at mid-day on the equinoxes2. that the sun will rise due east and set due west on the equinoxes (on all other days the sun will rise either north or south of east, and set north or south of west)3. the length of day and night are nearly equal

On this last point, they are not exactly equal, for two reasons:1. the sun appears as a disk in the sky with a radius of around 16 arc minutes, and so the top of the sun appears to rise while the centre of the disk is still below the horizon, and the instant of the equinox is measured with respect to the sun’s centre, and2. the sun’s light is bent, or refracted, in the Earth’s atmosphere, so that rays from the sun can light you up even before the sun rises, and keep you lit after it sets, with the degree of refraction being around 34 arcminutes These two factors combine to mean that the sun will appear to have “risen” when the centre of the disk is still 50 arcminutes (16 + 34) below the horizon, making the amount of daylight longer than the expected 12 hours. How much longer depends on where on Earth you are, but in the Delhi the length of the day is approx. 12 hours 7 minutes, rather than exactly 12 hours.

Due of this effect, the days on which the length of day and night are exactly equal, called the equilux, occur a few days before the spring equinox and a few days after the autumn equinox. This date will vary depending on where on the Earth you are, whereas the equinox is a fixed instant in time. In Delhi “Equilux” will happen on 16th March when sunrise and sunset would be at 06:30 and 18:30 IST!!!

This year’s Vernal Equinox slated for the 20th March at 16:57 UT or 22:27 IST

ASTRONOMY AT HOME Shadow Dance

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The purpose of this activity is to understand how the shadow moves with respect to the movement of light and also to understand the relationship between the angle of light source and the shadow's length. After conducting the activity we shall be able to understand how shadows form, how they behave based on different type of light sources and their correlation.

What You'll Need

1 – tube of glue1 – Square card Board of any size larger than 6” in size.1 – Square cardboard of 2”X2”1 – Gnomon1 – flashlight

What to Do

Cut a small square piece out of the cardboard an inch each side. Next, push a toothpick into the centre of the small cardboard piece. Put this piece on top of a larger piece of cardboard at one end.Shine your flashlight on the gnomon to create a shadow line. Try different ways of making the shadow line change its direction and its length.

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Contd.

1. Moving the Flashlight: Without moving the gnomon, make the direction of the

shadow line change by moving the flashlight.

E X P E R I M E N T

This way you will observe the shadow moving in the direction opposite to the direction in which you are moving the torch.  This is possible only when the source of light is close to the shadow casting object

2. Moving the Toothpick: Without moving the flashlight, but keeping it pointed at the

gnomon, move the gnomon around and observe what happens to the shadow.

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Contd.

3. Using the Sun as the Light Source: You can also form a shadow line by placing a gnomon under direct sunlight. This can be done by going outside. What happens to the shadow when you move the gnomon around in the sunlight? How is it similar or different to the shadow created by the flashlight?

What's going on?

As we move the source of light or board we will see the shadow moving in the opposite direction which tells us that shadow always falls in the opposite direction. The shadow will be longer and fainter as the source of light is far whereas it will be short and dark as the source is close to the gnomon.You should notice some interesting differences between shadows created by the flashlight and those created by the Sun. Because the Sun is so far away, you may have noticed that the angle of the shadow pointed in the same direction when you moved the gnomon whereas in case of the flashlight, the shadow moves in different angles, always opposite to the flashlight. Since the light source of the flashlight was much closer, the shadow behaved differently.Also one more thing we can observe is the length of shadow gets shorter when the source of light goes higher, almost vertical whereas it grows longer as the flashlight comes close to the board with light falling parallel to the board.

When you observe the shadow using the sunlight, the shadow will moves in the same direction which shows that the shadow will not change if the source of light is very far away.

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Contd.

Fill your observations in the Log Sheet. The log sheet will give you a quantitative analysis of the shadow movement with respect of the movement of source of light. One can learn and understand the motion of shadow with respect to the motion of light source.

Log sheet for Shadow Measurement

Serial Number Direction of Shadow Movement (Same or opposite)

Length of Shadow (in CM)

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Bonjour !!!! Euro Space Center, Belgium & France

Hurry !!!!Don’t miss the fun…

To Register email us @ getintouch@astrotourism.in

Come let’s explore the life of an

Astronaut at Euro Space Centre

Yummy visit to the chocolate factory

Lots of fun at Disneyland, Paris

Don’t wonder to see the world’s wonder ‘Eiffel

Tower’

Lose yourself in the mesmerizing beauty of

Rhine Fall

Spectacular snowy enjoyment even in summer

with ‘ROTAIR Gondola’

Plan your holidays at Astroport - Sariska

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A platform to

enlighten

your holidays

with fun,

where fun &

learning fuse

together !!!!

Serene environment

around wildlife

Groomed hospitality team to

welcome you

Feel the freshness of the

organic farm at site

Luxurious camp site

Enjoy the organic food

For booking, mail us @ getintouch@astrotourism.in

SPACE India is Hiring!!

We have been expanding very rapidly, and offer scope for rapid growth. We value entrepreneurial attitude and a result oriented approach. Above all, we are passionate and sincere about improving the science education scenario in India and the world. If you are interested in a satisfying career helping define what learning can be, then do apply to us. Current Career Opportunities

Operations Manager - Travel : 1 PositionDepartment : AstrotourismLocation : New Delhi

Educator :  3 PositionDepartment : EducationLocation : Chandigarh & Delhi

Sr. Executive - Client Relationship : 4 PositionDepartment : Sales & Marketing Location : Gurgaon & South Delhi

Sales Executive/ Sr. Executive Client Relationship : 1 PositionDepartment : Sales & Marketing Location : Noida

If you are interested please follow the link of company website to see the job details:

SPACE INDIAWebsite

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S P A C E G R O U P WEBSITESwww.space-india.com www.astrotourism.in www.space-india.org www.universeintheschool.com www.spacearcade.in www.leoplanetaria.com www.eclipsechasers.in www.astronomica.in

Follow us on

EMAIL US AT: getintouch@space-india.com

WZ-19 ASALATPUR, A3 BLOCK JANAK PURI WEST, NEW DELHI-110058 PH: +91-11-45086320, 25522193