Stonehenge

Apart from the mechanical devices made of metal, wood or ivory, some early astronomers relied on massive masonry structures for astronomical observations. Among the oldest such structures is the megalithic ruin known as Stonehenge in England. Stonehenge was constructed of 56 individual segments and was possibly used as a method of determining several astronomical events.

 Investigators over the last 100 years have revealed that Stonehenge was build in several stages from 2800-1800 BC. It seems to have been designed to allow for observation of astronomical phenomena - summer and winter solstices, eclipse and more. The stone pillars may have been constructed so that the alignment of the sun, with respect to the pillars, would allow astronomers to determine the beginnings and mid points of the seasons. Stonehenge may have been used as a tool to determine the position of the moon throughout the year, roughly predicting the occurrence of eclipses.

Sunspot Beauty

JP Brahic took this photo from France on April 5, 2013. He used a refractor Astro-Physics 155mm F/D 8.5 and a Bassler ACA1300 camera with filter H-Alpha 1A ° to capture the image.CREDIT: JP Brahic

Phobos: Facts About Martian Moon

NASA's Mars Reconnaissance Orbiter took this image of the larger of Mars' two moons, Phobos, from a distance of about 6,800 km (about 4,200 miles).
CREDIT: NASA/JPL/University of Arizona

Facts about Phobos:

• Radius of moon: 6.9 miles (11.1 km)
• Semi-major axis around Mars (distance from planet's center): 5,826 miles (9,376 km)
• Closest approach: 5,738 miles (9,234 km)
• Farthest approach: 5,914 miles (9,518 km) 
• Orbit eccentricity: 0.0151
• Orbit inclination: 1.075 degrees
• Time to make one orbit: 7.65 hours
• Mass: 1.0659 x 10^16 kg
• Density: 1.872 g/cm^3
• Surface gravity: 0.0057m/s^2
• Escape velocity: 25 mph (41 km/h)

See Jupiter and Moon Close Together Monday

Stargazers looking up as darkness falls on Monday (Jan. 21) will notice an eye catching pairing-off between two of the brightest objects in the nighttime sky, weather permitting. 

Question 107: 22 October 2012 (Week 43)

Q107: What is Neutron star?

Instruments used in Indian Astronomy Long ago

Among the devices used for astronomy was Gnomon, known as Sanku, in which the shadow of a vertical rod is applied on a horizontal plane in order to ascertain the cardinal directions, the latitude of the point of observation, and the time of observation. This device finds mention in the works of Varāhamihira, Āryabhata, Bhāskara, Brahmagupta, among others. The Cross-staff, known as Yasti-yantra, was used by the time of Bhaskara II (1114–1185 CE). This device could vary from a simple stick to V-shaped staffs designed specifically for determining angles with the help of a calibrated scale. The clepsydra (Ghatī -yantra) was used in India for astronomical purposes until recent times. Ōhashi (2008) notes that: "Several astronomers also described water-driven instruments such as the model of fighting sheep."

Interesting Facts About Moon

There are many interesting facts about the moon and trivia that may or may not be important to you. Some interesting facts include:

• We all know there was a man on the moon, but did you know that there is one who stayed there? Dr. Eugene Shoemaker, a Geological Surveyor, who educated the Apollo mission astronauts about craters, never made it into space himself, but it had always been one of his dreams. He was rejected as an astronaut because of medical problems. After he died, his ashes were placed on board the Lunar Prospector spacecraft on January 6, 1999, which was crashed into a crater on the moon on July 31, 1999. The mission was to discover if there was water on the moon at the time, but it also served to fulfill Dr Shoemaker's last wish.

I am Proud to be Indian - Image from Past -1981

SOURCE: ISRO

Amazing, Interesting, and Strange Astronomy facts

 ·                     Scientists believe that we can only see about 5% of the matter in the Universe. The rest is made up of invisible matter (called Dark Matter) and a mysterious form of energy known as Dark Energy.
 
·                     Neutron stars are so dense, that a soup can full of neutron star material would have more mass than the Moon.
 
·                     The Sun produces so much energy, that every second the core releases the equivalent of 100 billion nuclear bombs.
 
·                     Galileo Galilei is often incorrectly credited with the invention of the telescope. Instead, historians now believe the Dutch eyeglass maker Johannes Lippershey as its creator. Galileo was, however, probably the first to use the device to study the heavens.
 
·                     Black Holes are so dense, and produce such intense gravity, that even light can not escape. Theoretical physicists predict that there are situations under which light can escape (which is called Hawking radiation).
 
·                     Light from distant stars and galaxies takes so long to reach us, that we are actually seeing objects as they appeared hundreds, thousands or even millions of years ago. So, as we look up at the sky, we are really looking back in time.
 
·                     The Crab Nebula was produced by a supernova explosion in 1054 A.D. The Chinese and Arab astronomers at the time noted that the explosion was so bright, that it was visible during the day, and lit up the night sky for months.
 
·                     Shooting stars are usually just tiny dust particles falling through our atmosphere. Comets sometimes pass through Earth’s orbit, leaving trails of dust behind. Then as Earth plows through the dust in its path, the particles heat up, creating the streaks in the night sky.

Interesting Facts - Space

• Any free-moving liquid in outer space will form itself into a sphere, because of its surface tension.
• Mercury, Venus, earth and Mars are called the inner planets as they are closest to the sun!
• December 21st 1968, was the first time that humans truly left Earth, when Apollo 8 became the first manned space vehicle to leave Earth orbit and to orbit the Moon.
• Olympus Mons, a volcano found on Mars, is the largest volcano found in solar system. It is 370 miles (595 km) across and rises 15 miles (24 km).
• We know more about space than we do about our deep oceans!

Answer to Question 78

Planetary Motion

Since, long, scientists have been trying to know the

Heliocentric Solar system

universe around them. They have taken great interest in the motion of heavenly bodies like sun, planets, moon etc. Ptolemy, a Greek astronomer proposed theory regarding the planetary motion. His theory was called Geocentric Theory of Planetary Motion. According to this theory, all the heavenly bodies like sun, stars, planets, moon etc. are moving around the earth, which is stationary and is taken as the centre of the universe. Copernicus challenged this theory.

In 498 A.D. a great Indian mathematician and astronomer,Arya-Bhatta, from his observations concluded that the various facts (like solar eclipse, moon eclipse, formation of day and night etc.) could be very easily explained by considering that earth revolves round the sun and also rotates on its own axis. However, due to lack of communication, his ideas could not be communicated to the western philosophers.

Geocentric Solar system

In 1543, Copernicus suggested that description of motion of heavenly bodies becomes very simple and more properly explained if we assume that sun is stationary and earth as well as other planets is revolving around it. This theory was called Heliocentric theory. Galileo later on supported this theory from his experimental study on moon and other planets.

We will now see the various constituents of the universe.

Interesting Facts of Space Travel

• The first manmade satellite to be successfully launched into orbit was sputnik 1 in 1957 by the soviets. The first USA satallite, the explorer was launched in 1958. 
• Yuri Gararin from the USSR made the first successful manned space flight in 1961. The first manned space flight by American was made by Scot Glen in 1962. 
• Russian cosmonaut Valeri Polyakov, holds the record for most days spent in space. He achieved 438 days aboard the Mir space station. 
• Valentina Tereshkova USSR was launched into space on 16 June 1963 to become the first woman in space. American woman didn't get into space until Sally Ride blasted off in 1983. 
• On 20 July 1969 Neil Armstrong is the first person to walk on the moon as he does so he uttered those famous words "That's one small step for man, one giant leap for mankind. The first meal consumed on the moon was turkey from foil packets. Only twelve people in total (all men) have walked on the surface of the moon. 
• There have been 18 fatalities during spaceflight. 13 Americans 1 Israeli and 4 USSR cosmonauts. 
• Gene Roddenberry the creator of Star Trek was one of the first to be have a space burial. His ashes were sent into orbit in 1997. 
• Dennis Tito, aged 60, became the first space tourist after he reportedly paid the Russians $20 million for the privilege. 
• The first animals sent into space were fruit flies aboard a V2 rocket launched by the Americans in 1947 

Looking back in time

Light from distant stars and galaxies takes so long to reach us, that we are actually seeing objects as they appeared hundreds, thousands or even millions of years ago. So, as we look up at the sky, we are really looking back in time.

If two pieces of metal touch in space, they become permanently stuck together

This may sound unbelievable, but it is true. Two pieces of metal without any coating on them will form in to one piece in the vacuum of space. This doesn’t happen on earth because the atmosphere puts a layer of oxidized material between the surfaces. This might seem like it would be a big problem on the space station but as most tools used there have come from earth, they are already coated with material. In fact, the only evidence of this seen so far has been in experiments designed to provoke the reaction. This process is called cold welding. 

Light coming from sun reaches to earth in 30000 years - Interesting Fact

The energy in the sunlight we see today started out in the core of the Sun 30,000 years ago – it spent most of this time passing through the dense atoms that make the sun and just 8 minutes to reach us once it had left the Sun! 

The temperature at the core of the sun is 13,600,000 kelvins. All of the energy produced by fusion in the core must travel through many successive layers to the solar photosphere before it escapes into space as sunlight or kinetic energy of particles.

Galaxies Shaped Like the Alphabet

The online Galaxy Zoo project has found galaxies shaped like every letter of the alphabet.

CREDIT: Galaxy Zoo 

Our cosmos is a veritable alphabet soup, featuring galaxies that resemble every letter from A to Z, volunteers participating in the online Galaxy Zoo project have found.

Since 2007, Galaxy Zoo has been asking regular folks around the world to classify galaxies by shape. So far, more than 250,000 people have sorted through roughly 1 million images, saving scientists precious time and helping reveal key insights about galaxy formation and evolution, project officials say.

The moon is moving away from Earth - Interesting Fact

Every year the moon moves about 3.8cm further away from the Earth. This is caused by tidal effects. Consequently, the earth is slowing in rotation by about 0.002 seconds per day per century. Scientists do not know how the moon was created, but the generally accepted theory suggests that a large Mars sized object hit the earth causing the Moon to splinter off.

We are moving in space at 530Km/s - Interesting Fact

Our Galaxy – the Milky Way is spinning at a rate of 225 kilometers per second. In addition, the galaxy is travelling through space at the rate of 305 kilometers per second. This means that we are traveling at a total speed of 530 kilometers (330 miles) per second. 

That means that in one minute you are about 19 thousand kilometers away from where you were. Scientists do not all agree on the speed with which the Milky Way is travelling – estimates range from 130 – 1,000 km/s. It should be said that Einstein’s theory of relativity, the velocity of any object through space is not meaningful.