30 September 2011

Mars in Beehive cluster

On 1st and 2nd October morning the red planet Mars will be in Beehive cluster in the constellation of Cancer. Mars rises at 2am and by 3:30am will be in good position to observe and photograph. Grab the binoculars and enjoy the Mars stay in Beehive cluster. Beehive cluster or M44 as its known, is 3rd magnitude open cluster visible easily as hazy patch to unaided eye. Binoculars and telescope will help in resolving the cluster.

26 September 2011

Sunspots viewing at ABAA

On Sunday afternoon the sky was clear and this prompted ABAA members T S Madhava, Naveen and Natraj to take out the association's 6inch telescope to show general public the Sunspots and also safe methods of observing the Sunspots. Members also explained the reasons for Sun spots to the curious public. The response was really good with a question and answer session which continued till the sun set.

Here are few photos of the session:

Naveen, Natraj and Madhava setting up the telescope and focusing Sunspots.

Madhava, Naveen and Natraj making final adjustments.
Madhava happy with public response

Public viewing the Sunspot and discussing

Naveen showing Sunspots to Students

ABAA members enjoy Sunspots before Sun disappears behind the tall buildings.

Uranus in Opposition

Uranus will be in opposition today in the constellation of Pisces. When a planet, Earth and the Sun make a straight line with the Earth at the centre, the planet is said to be in opposition.  As the planet rises when the Sun sets, it gives full night for observing the planet.  The mean distance of the planet Uranus at opposition is 2.72 billion kilometres with a magnitude of 5.5 which is an easy target for even small pair of binoculars.
Here are carts that will be helpful in locating the planet. The sky charts are made for 8pm local time, by this time the great square will be in good altitude in the eastern horizon. First get the bright 2.8 magnitude gamma pegasi in the binocular field, then move south around 9degrees to get Omicron Piscim a 4th magnitude star. Move the binocular 7 degrees south east of Omicron Piscium to get the planet Uranus in the field.
Rising time for Uranus for coming days:

September 26th Uranus will rise at 18:12
September 28th Uranus will rise at 18:04
October 1st Uranus will rise at 17:52
October 4th Uranus will rise at 17:40
October 10th Uranus will rise at 17:15
October 16th Uranus will rise at 16:50

14 September 2011

AstroNews: NASA's Webb Telescope Completes Mirror-Coating Milestone

NASA’s James Webb Space Telescope has reached a major milestone in its development. The mirrors that will fly aboard the telescope have completed the coating process at Quantum Coating Inc. in Moorestown, N.J.

The telescope's mirrors have been coated with a microscopically thin layer of gold, selected for its ability to properly reflect infrared light from the mirrors into the observatory’s science instruments. The coating allows the Webb telescope's "infrared eyes" to observe extremely faint objects in infrared light. Webb’s mission is to observe the most distant objects in the universe.

"Finishing all mirror coatings on schedule is another major success story for the Webb telescope mirrors," said Lee Feinberg, NASA Optical Telescope Element manager for the Webb telescope at the agency’s Goddard Space Flight Center in Greenbelt, Md. "These coatings easily meet their specifications, ensuring even more scientific discovery potential for the Webb telescope."

The Webb telescope has 21 mirrors, with 18 mirror segments working together as one large 21.3-foot (6.5-meter) primary mirror. The mirror segments are made of beryllium, which was selected for its stiffness, light weight and stability at cryogenic temperatures. Bare beryllium is not very reflective of near-infrared light, so each mirror is coated with about 0.12 ounce of gold.

The last full size (4.9-foot /1.5-meter) hexagonal beryllium primary mirror segment that will fly aboard the observatory recently was coated, completing this stage of mirror production.

The Webb telescope is the world’s next-generation space observatory and successor to the Hubble Space Telescope. The most powerful space telescope ever built, the Webb telescope will provide images of the first galaxies ever formed, and explore planets around distant stars. It is a joint project of NASA, the European Space Agency and the Canadian Space Agency.

Mirror manufacturing began eight years ago with blanks made out of beryllium, an extremely hard metal that holds its shape in the extreme cold of space where the telescope will orbit. Mirror coating began in June 2010. Several of the smaller mirrors in the telescope, the tertiary mirror and the fine steering mirror, were coated in 2010. The secondary mirror was finished earlier this year.

Quantum Coating Inc. (QCI) is under contract to Ball Aerospace and Northrop Grumman. QCI constructed a new coating facility and clean room to coat the large mirror segments. QCI developed the gold coating for performance in certain areas, such as uniformity, cryogenic cycling, durability, stress and reflectance, in a two-year effort prior to coating the first flight mirror.

In the process, gold is heated to its liquid point, more than 2,500 Fahrenheit (1,371 degrees Celsius), and evaporates onto the mirror's optical surface. The coatings are 120 nanometers, a thickness of about a millionth of an inch or 200 times thinner than a human hair.

"We faced many technical challenges on the Webb mirror coating program,” said Ian Stevenson, director of coating at Quantum Coating. “One of the most daunting was that all flight hardware runs had to be executed without a single failure."

The mirror segments recently were shipped to Ball Aerospace in Boulder, Colo., where actuators are attached that help move the mirror. From there, the segments travel to the X-ray and Calibration Facility at NASA's Marshall Space Flight Center in Huntsville, Ala., to undergo a final test when they will be chilled to -400 Fahrenheit (-240 degrees Celsius). The last batch of six flight mirrors should complete the test by the end of this year.

The Webb telescope is a partnership between NASA, the European Space Agency and the Canadian Space Agency.