26 Jan 2009

Credit & Copyright: Naveen Nanjundappa

The Royal Observatory, Greenwich was commissioned in 1675 by King Charles II, At this time the king also created the position of Astronomer Royal to serve as the director of the observatory.

Charles II appointed John Flamsteed as his first Astronomer Royal in March 1675. The Observatory was built to improve navigation at sea and ‘find the so-much desired longitude of places’ – one’s exact position east and west – while at sea and out of sight of land, by astronomical means. This was inseparable from the accurate measurement of time, for which the Observatory became generally famous in the 19th century.

Tomorrow’s picture - Andromeda Galaxy.

25 Jan 2009

Credit & Copyright: Prasanna Ramaswamy

The Iridium communication satellites have a peculiar shape with three polished door-sized antennas, 120 degrees apart and at 40 degree angles with the main bus. The forward antenna faces the direction in which the satellite is travelling. Occasionally an antenna will reflect sunlight directly down to the Earth, creating a predictable and quickly moving illuminated spot of about 10 km diameter. To an observer this looks like an extremely bright flare in the sky with a duration of a few seconds.

One can get the accurate prediction of when and where we can see Iridium flares.

Fixed tripod astrophotograpy techniques can be used to capture Iridium Flare and other satellite flares.

Tomorrow’s picture - Royal Observatory Greenwich.

24 Jan 2009

The Vainu Bappu Observatory is located about 175 km south-east of Bangalore, and about 200 km south-west of Chennai .

Vainu Bappu Telescope is the Largest Optical Telescope in Asia with a diameter of 2.3 meters. At its prime focus we find High-Resolution Echelle Spectrograph attached.

The telescope is so powerful that it can easily resolve a 25 paisa coin kept forty kilometers away. That’s the power of Size !

Tomorrow’s picture - Iridium Flare.

23 Jan 2009

Above Picture taken on 29 Dec 2008, show beautiful conjunction of Planet Jupiter ( lower right ), Mercury ( lower left ) and Moon.

Fixed tripod astrophotograpy techniques can be used to capture conjuntion on celestial objects.

Tomorrow’s picture - Size does Matter.

22 Jan 2009

Stonehenge is a prehistoric monument located in the English county of Wiltshire, Its one of the most famous prehistoric sites in the world, But recent observations show Stonehenge was a place of burial.

Stonehenge was produced by a culture with no written language, and at great historical remove from the first cultures that did leave written records. Many aspects of Stonehenge remain subject to debate. This multiplicity of theories, some of them very colourful, is often called the “mystery of Stonehenge.”

There is little or no direct evidence for the construction techniques used by the Stonehenge builders.

Tomorrow’s picture - Jupiter, Mercury and Moon.

21 Jan 2009

Image Details : Canon EOS 450D, ISO: 400, Exposure: 3.2 sec, Aperture: 4.5, Focal Length: 29mm

The term conjunction primarily refers to a phenomenon defined only for the position of the observer, not just to a celestial relationship. It means that, as seen from the Earth, two celestial bodies appear near one another in the sky. The event is also sometimes known as an appulse.

Tomorrow’s picture - Stone Henge.

20 Jan 2009

Image Details : Canon EOS 450D, ISO:400, Exposure: 1/20 sec, Prime Focus using newtonian reflector 5.5 inch telescope.

The word crater was adopted by Galileo from the Latin word for cup. Galileo built his first telescope in late 1609, and turned it to the Moon for the first time on November 30, 1609. He discovered that, contrary to general opinion at that time, the Moon was not a perfect sphere, but had both mountains and cup-like depressions, the latter of which he gave the name craters.

Impact craters are the remains of collisions between an asteroid, comet, or meteorite and the Moon. The surface of the moon is scarred with millions of impact craters. There is no atmosphere on the moon to help protect it from bombardment from potential impactors. There is no erosion (wind or water) and little geologic activity to wear away these craters, so they remain unchanged until another new impact changes it.

Tomorrow’s picture - Conjunction.

19 Jan 2009

Image Details : Canon EOS 450D, ISO: 800, Exposure: 358.0 sec (Manually tracked), Aperture: 3.5, Focal Length: 18mm

The Orion Arm is a minor spiral arm of the Milky Way galaxy. The Solar System and Earth are within the Orion Arm. It is also referred to as the Local Arm, the Local Spur or the Orion Spur.

The Orion Arm is named for its proximity to the stars in the Orion constellation. It is located between the Sagittarius Arm and the Perseus Arm, two of the four major arms of the Milky Way. Within the Orion Arm, the solar system and Earth are located close to the inner rim in the Local Bubble, approximately 8000 parsecs (26,000 light-years) from the galactic center.

Above picture is taken with camera mounted “piggyback” on a telescope. With a long exposure time. In order to take longer exposures that track on the stars so they do not trail, the camera must be mounted on an equatorial mounting that is correctly polar aligned.

Tomorrow’s picture - Moon.

17 Jan 2009

The Orion Nebula is an example of a stellar nursery where new stars are being born. Observations of the nebula have revealed approximately 700 stars in various stages of formation within the nebula.

Orion includes the prominent asterism known as the ‘belt’ of Orion: three bright stars in a row. Because they are so bright and distinctive, the pattern of stars that forms Orion was recognized as a coherent constellation by many ancient civilizations, though with different representations and mythologies.

Tomorrow’s picture - Wide star field.

16 Jan 2009

The star trails are caused by the rotation of the earth during the period of time when the camera’s shutter is held open.

Star trails of as above give us the visual proof that polestar is not perfectly positioned towards Earth north. star trails of Polestar, Ursa Major are very clear and they all appear to go round in concentric circles around the North Celestial Pole.

Set Your camera to the “bulb” mode, and a cable release to control. Generally, you should set the camera on the widest aperture that your lens support using a camera on a fixed tripod. You can take couple of minutes to hours depending on the sky conditions. Most of the star trails pictures are hours long. Try this and you will enjoy the final photo.

Tomorrow’s picture - Orion Nebula.

09 Jan 2009

Above picture shows two full moons taken by thro a 5.5 inch newtonian reflector telescope 6 months apart.

A simple photography project can be taken by students and amature astronomers, taking full moon photos every month for 1 year can clearly show the changes in the size of Moon due to its elicptical orbit round the earth.
The nearest point(Perigee) and farthest point(Apogee) on Moon orbit differs by approximately 55,000 Kms !!

Once can take photos of Planets (Mercury, Venus, Mars, Jupiter, Saturn) and Moon’s Phase regularly, Overlap the photos taken over a period of time, to get beautiful photo showing path of these celestial bodies in the sky.

Many interesting facts can be deduced by having a collection of full Moons photos, Planetary Conjunctions and Occultations.

So what are you waiting for? Get ready with your camera and be an Astro-Photographer.

Tomorrow’s picture - Star Trails.

08 Jan 2009

Above picture was taken during my observation sessions during the last week of Dec 2008. Lakshmisagara, a small village in Tarikere, Karnataka. An absolutely delight place for night sky.

The experience was very nice, I was alone and didn’t get the cable release for my camera to operate in bulb mode. I decided to use my laptop to start and stop the camera. while I connected the camera and laptop, I realised the delay in switching from laptop to telescope to manually guide I would get a trail. I thought for a while and found my mobile free., why not connect my mobile to my laptop. so that I press the key on my mobile, it would press the key on camera remote software from Canon. thus giving me a freedom to stay away from my laptop.

The story was not over at this point., Some of the problems were still not solved, there was no one to tell me how much time has passed for each exposure, how much is pending. So I decided to use my mobile with a alarm for every 10 min. so i would start and stop between the alarm beeps !

Thus I managed to track manually and the experience was fantastic ! I’m sure you can understand how I did this

I experimented with exposure times of 3 min, 5 min and 10 min with manual tracking. I used 5.5 inch newtonian reflector with equ mount for tracking.

Tomorrow’s picture - Biggest full moon of Year 2008.

24 July 2008

When the Moon travels completely into the Earth’s umbra, one observes a total lunar eclipse. The Moon’s speed through the shadow is about one kilometer per second (2,300 mph), and totality may last up to nearly 107 minutes. Nevertheless, the total time between the Moon’s first and last contact with the shadow is much longer, and could last up to 3.8 hours. The relative distance of the Moon from the Earth at the time of an eclipse can affect the eclipse’s duration.

Left image show moon before eclipse and right image during total lunar eclipse.

Tomorrow’s picture - Saturn.

23 July 2008

A partial eclipse occurs when the Sun and Moon are not exactly in line, and the Moon only partially obscures the Sun. This phenomenon can usually be seen from a large part of the Earth outside of the track of an annular or total eclipse. However, some eclipses can only be seen as a partial eclipse, because the umbra never intersects the Earth’s surface.

Tomorrow’s picture - Total Lunar eclipse.

22 July 2008

Between 1727 and 1734 Maharajah Jai Singh II of Jaipur constructed five astronomical observatories in west central India. The observatories, or “Jantar Mantars” as they are commonly known, incorporate multiple buildings of unique form, each with a specialized function for astronomical measurement. These structures with their striking combinations of geometric forms at large scale, have captivated the attention of architects, artists, and art historians world wide, yet remain largely unknown to the general public.

Tomorrow’s picture - Partial Solar eclipse.

21 July 2008

Coming close to Full moon, Most of the large surface features of moon can be clearly seen.

ISO 400, 1/80 Sec, using Canon 450D DSLR Camera and newtonian reflector telescope.

Tomorrow’s picture - Jantar Mantar.

18 July 2008

Bright object is Jupiter and the Cloudy Bright and dark Patch is Sco milkyway region.

ISO 1600, 10X30 Sec, f5.4 untracked @ 18 mm, using Canon 450D DSLR Camera.
Photograph Date : 04.06.2008

Tomorrow’s picture - Full Moon

17 July 2008

This picture shows the details of moon surface. Sinus roris ( upper right) Sinus Iridum and Mare ( centre and below)

Tomorrow’s picture - Arm of Milkyway Galaxy

16 July 2008

Tomorrow’s picture - Close up Moon

11 Feb 2007

The border between the constellations Perseus und Cassipeia is a beautiful Autumn Milky Way area full of multi-colored stars and red emission nebulae. The two “double objects” dominate this region: The Double Cluster NGC 884 and NGC 869, these objects are located “nearby” in the Perseus arm of our galaxy.

Although extremely large, the Double Nebulae are very faint, for a good visual observation you will need a rich-field telescope. The Double Cluster however is a showpiece object that can even be seen with the unaided eye.

Tomorrow’s picture - Moon and Saturn

10 Feb 2007

A supernova is a stellar explosion which produces an extremely luminous object that is initially made of plasma—an ionized state of matter. A supernova may briefly out-shine its entire host galaxy before fading from view over several weeks or months

The explosion expels much or all of a star’s material at a velocity up to a tenth the speed of light, driving a shock wave into the surrounding interstellar gas. This shock sweeps up an expanding shell of gas and dust called a supernova remnant.

A supernova is a relatively rare event that occurs, on average, only once every 50 years in a galaxy the size of the Milky Way

Several large stars within the Milky Way have been suggested as possible supernovae within the next few thousand to hundred million years. These include Rho Cassiopeiae, Eta Carinae, RS Ophiuchi, the Kitt Peak Downes star KPD1930+2752, HD 179821, IRC+10420, VY Canis Majoris, Betelgeuse, Antares, and Spica.

Above picture is just a false image ( moon hidden in the clouds ) which appears as a supernova.

Tomorrow’s picture - Double cluster region of Cassiopeia

9 Feb 2007

Crux, The Southern Cross is the smallest constellation in the sky, very distinct and most famous. It lies in the rich region of the Milkyway, on the border of Centaurus.

If you use the Southern Cross to find south, be careful to distinguish it from the False Cross. The Southern Cross is somewhat kite-shaped, and it has a fifth star (ε Crucis). The False Cross is diamond-shaped and does not have a fifth star like ε Crucis.

The five brightest stars of Crux (α, β, γ, δ, and ε Crucis) appear on the flags of Australia, Brazil, New Zealand (epsilon omitted), Papua New Guinea, and Samoa, and also the Australian States and Territories of Victoria, the Australian Capital Territory, the Northern Territory, as well as the flag of Magallanes Region of Chile, and several Argentine provincial flags and emblems.

Trishanku character is associated with crux in Hindu mythology !

Tomorrow’s picture - False Supernova

8 Feb 2007

The Moon is Earth’s only natural satellite. The average distance from the Earth to the Moon is 384,399 kilometres, which is about 30 times the diameter of the Earth.

The Moon is about one-third the size of the Earth and has a diameter of 3,474 kilometres. It is the fifth largest moon in the Solar System behind Ganymede, Titan, Callisto, and Io.

During the brightest full moons, the Moon can have an apparent magnitude of about −12.6 When the Moon is in a quarter phase, its brightness is not one half of a full moon, but instead is only about 1/10. This is because the lunar surface is not a perfect Lambertian reflector and because shadows projected onto the surface also diminish the amount of reflected light.

Tomorrow’s picture - Southern Cross

7 Feb 2007

Above picture shows the best way of observing sunspots, solar eclipse.
while trying to align the telescope towards sun DON’T look through the view finder or eyepiece.

Projection of sun’s image on to a sheet of paper is safe and allow multiple people to observe at the sametime.

Tomorrow’s picture – Moon raising.

6 Feb 2007

The Summer Triangle is an astronomical asterism involving an imaginary triangle drawn on the northern hemisphere’s celestial sphere, with its defining vertices at Altair, Deneb, and Vega. This triangle connects the constellations of Aquila, Cygnus, and Lyra.

Bright Vega is in Lyra, the Harp. Deneb is the tail of Cygnus, the Swan. Altair is in Aquila, the Eagle.

Vega (center left ) – 25 lightyears away has an magnitude of 0.03
Deneb (lower left) – 3230 lightyears away has an magnitude of 1.25
Altair (center right) – 16.6 lightyears away has an magnitude of 0.77

Tomorrow’s picture - Safe Sun Spots Observation using Telescope.

5 Feb 2007

A sunspot is a region on the Sun’s surface, Sunspots are “dark” because they are cooler than their surroundings. Sunspots are only dark in contrast to the bright face of the Sun.

If you could cut an average sunspot out of the Sun and place it elsewhere in the night sky, it would be about as bright as a full moon. Sunspots have a lighter outer section called the penumbra, and a darker central region named the umbra.

Sunspots are caused by disturbances in the Sun’s magnetic field welling up to the photosphere, the Sun’s visible “surface”. The powerful magnetic fields in the vicinity of sunspots produce active regions on the Sun, which in turn frequently spawn disturbances such as solar flares and Coronal Mass Ejections

Sunspots form over periods lasting from days to weeks, and can persist for weeks or even months before dissipating. The average number of spots visible on the face of the Sun is not constant, but varies in a multi-year cycle. Historical records of sunspot counts, which go back hundreds of years, verify that this sunspot cycle has an average period of roughly eleven years.

Our Sun isn’t the only star with spots. In recent years, astronomers have been able to detect “starspots” – “sunspots” on other stars.

Above picture shows the sunspots as seen on 3 Feb 2007.

Don’t look at Sun directly through the telescope or binocular.

Tomorrow’s picture – Summer Triangle

4 Feb 2007

A few weeks before I was invited to give a public talk on Comets and Asteroids, organised by the group called “Manthana”.

The talk covered topics like Potentially Hazardous Asteroids, Orbits of Earth crossing Asteroids, Origin of Asteroids and Comets, Myths.. and so on.

Slide visible in the photo shows the distribution of asteroids between the orbit of Mars and Jupiter.

Tomorrow’s picture - Sun Spots

3 Feb 2007

Sagittarius is a constellation of the zodiac, commonly depicted as a centaur drawing a bow.

This constellation is located in Milkyway rich stars region of sky, hence Sagittarius contains many star clusters and nebulae.

Lagoon Nebula (M8) is a giant interstellar cloud and H II region, in the constellation Sagittarius. At an estimated distance of 4,100 light-years, the Lagoon is one of only two star-forming nebulae faintly visible to the naked eye.

The Western astrological sign Sagittarius of the tropical zodiac (November 22–December 21) differs from the astronomical constellation and the Hindu astrological sign of the sidereal zodiac (December 18–January 18).

Tomorrow’s picture - Public Talk on Comets and Asteriods.

2 Feb 2007

Bootes, the Herdsman, rises, its kite-shaped figure stretching up and to the left of the bright orange star Arcturus.

There are many Myths, Bootes was identified with a farmer who plows the land during spring. The Romans called Bootes the Herdsman of the Septemtriones, that is, of the seven oxen represented by the seven stars of the Big Dipper, which was seen as the cart or the plow.

Boötes was also supposed to have invented the plough. This is said to have greatly pleased Ceres, the goddess of agriculture who asked Jupiter to give Boötes a permanent fixture in the heavens as a reward for doing this.

Another version portrays Boötes as a grape grower called Icarius, who one day invited the Roman god Bacchus, also called Dionysus, to inspect his vineyards. Bacchus revealed the secret of wine making to Icarius, who was so impressed by this alcoholic beverage that he invited his friends round to sample it. Having never tasted wine before, they all drank too much and woke up the next morning with terrible hangovers; and they made the mistaken assumption that Icarius had tried to poison them. It was decided that Icarius should pay the price with his own life, and he was swiftly murdered in his sleep. Bacchus placed Icarius in the stars to honor him.

Tomorrow’s picture – Sagittarius and M8

1 Feb 2007

Canis Major was one of the most important constellations in ancient times because the brightest star in the sky is part of it. The brightest star in this constellation is Sirius, often called the Dog Star.

To identify this constellation, first locate Orion and imagine a straight line through his belt towards southeast, and you will see Sirius perched right below it, which is the eye of the dog.

In Egyptian history it was identified with the goddess Isis, with the cow-goddess Hathor and with the jackal-headed god Anubis. Greeks recognised Canis Major as the largest of Orion’s two hunting dogs and chasing Lepus (the Rabbit) who is just in front of him.

Tomorrow’s picture – Bootes, the Herdsman.