Japanese Solar Sail Craft controls its direction using LCDs

This is innovation at its best. Scientists at JAXA (the Japan Aerospace Exploration Agency) not only created a satellite with solar sails (something poor guys at the planetary society will probably be fuming at) but created an innovative method to control its attitude, not by using rocket motors but a simple liquid crystal display. Yes this is the same stuff used to make the displays in your calculators and watches!

The liquid crystal device on the craft is a thin-film instrument that changes the surface reflection characteristics of sunlight by turning on and off the power of the device.

Location of the LCDs on the IKAROS craft, Image Courtesy: JAXA

For the uninitiated, a solar sail works just like an ordinary wind-sail. The major difference being that instead of wind, it uses pressure generated by incident light radiation from the sun. When electromagnetic radiation is incident on a solid, it exerts a small force on the target, that may cause it to move. Solar sails ave potential application in deep space missions, as the maximum theoretical speed gained from a solar sail is the speed of light!

The difference in solar pressure is used to generate torque and re-orient the spacecraft.

The IKAROS was launched from the Tanegahima Space Center on May 21, 2010.

Related Links:
How Solar Sails work
Planetary Society Solar Sail Initiative

Romancing the Skies

Bookmark and Share

It all started in the second week of june when Ajay Talwar (AAAD), one of the most talented Astro-photographers of the country called me and said that he was planning to revisit The Indian astronomical Observatory at Hanle, Ladakh after our successful 2008 visit. How could I possibly say no? Off course I would go.

We were soon joined by another member from our last expedition Vikrant Narang (SPACE) . After Days of planning and multiple trips to Ajay’s place, we decided different kinds of photography we would be doing at Hanle Observatory. These included Morse code star trails, trails using fisheye lens, time-lapse videos and many other kinds… By the time we finished the planning we were to carry equipment of that weighed almost 150 Kgs by airplane from Delhi to Leh and then beyond to Hanle.

Finally June 30th it was time to fly to Leh. As popular websites suggested we started Diamox two days before starting our journey. After paying a hefty amount for extra luggage our flight landed at one of world’s highest airport The Kushok Bakula Rimpochee Airport (10,682ft) at leh with just about 60% of the oxygen as compared to sea level left in the atmosphere. The first thing you do is go to sleep. Total bed rest for the first 48 hours is the only method to acclimatize to high altitude. From my last experience I had realized that the first signs of Acute Mountain Sickness or AMS show within a few hours of rapid ascend. Fortunately enough after a complete day of rest nothing happened, giving credits to our medicine friend Diamox we went out to the Leh market, which was just a 10 min walk up the hill. We had our dinner at the famous German Bakery (highly recommended) their Italian and Lebanese food is fantastic there..Anyways we went back to Indian Institute of Astrophysics guest house where we again rested.

Next day woke up late and then went to Lamdon Model School in Leh to give a half an hour presentation about our expedition and to popularize astronomy amongst the kids who were very enthusiastic and post presentation started requesting their teacher to take them to Hanle Observatory. Later in the day we went for a little recce to look for a good site to do the night photography we had planned we would be doing in Leh city. We fixed two spots for the night under the stars one was the famous Shanti stupa which is the highest point near the city from here we could see the entire city, the Stok glacier and the sky beyond giving a beautiful panoramic view of the entire valley. The other location we chose was a roof of a cute little café right in the middle of leh city, the terrace provided us an awesome view of the famous leh palace, the Jamia Masjid , The local Buddhist Temple, and the entire Old Leh Market.

As the night approached we set up our equipment, Vikrant went to Shanti Stupa to click a multiple camera panorama, Me and Ajay went upto the café terrace to setup the 7 feet long camera track to capture a series of images to be processed to form a movie later on….. This is what we captured that night….

Click on photo to enlarge

Click on photo to enlarge
More about the trip and journey from Leh to Hanle and back to Delhi to follow…. Many more pretty pictures to come as well

Raghu Kalra

you can send your feedback to us on astronomydelhi(@)gmail.com