Space And Universe
1.What is Universe?
The vast empty space around us that consists of stars, planets and enormous clouds of dust and gas is called Universe.
2.How was the Universe formed?
The Big Bang was the event which led to the formation of the Universe. It happened about 15 billion years ago. Atomic particles joined together to make the gases, helium (He) and hydrogen (H), within minutes of explosion. For more than millions of years, these gases formed the Universe and all the stars and galaxies within it. Mass and energy in the. Universe were created due to this explosion.
3.Is Space empty?
Not really. Matter was created almost as soon as the Universe began. Space is littered with stars and gas clouds. made almost entirely of two elements: the gases, hydrogen and helium. There are other elements too, such as iron, carbon and oxygen, but these are rare. The space between stars and planets are full of bits of space debris, including very tiny specks of dust and larger pieces of rock. Some of this space-dust forms clouds, called nebulae.
Space And Universe
1.In Space, how are heavenly bodies held together?
The Universe is held together by gravity, electromagnetism and strong and weak nuclear forces. These four forces keep the different heavenly bodies of the Universe in their place.
2.What is nebula?
A nebula is a cloud of gas and just in space. Some nebulae are regions where new stars are being formed, while others are the remains of dead or dying stars.
3.What is dark matter?
Roughly 80 percent of the mass of the Universe is made up of material that scientists cannot directly observe. This is known as dark matter. Unlike normal matter, dark matter does not absorb, reflect or emit light, making it extremely hard to spot. In fact, researchers have been able to infer the existence of dark matter only from the gravitational effect it ems to have on visible matter.
Space And Universe
1.When did the Universe begin?
Scientists have argued about this for centuries. At the moment, most people agree that the Universe began between 12 and 15 billion years ago. It all started with a mind-boggling explosion called the Big Bang.
2.What was the Big Bang?
It was a huge explosion, that created all the mass and energy in our Universe in
less than a second! The effects of the blast are so strong that the Universe is still expanding.
3.What if the Big Bang happened again?
It cannot happen again in our Universe, but some people think it may be happening millions of times making millions of different universes. Only a few would last as long as ours – most would pop like soap bubbles.
Space And Universe
1.What are asteroids?
Asteroids are small, rocky, irregular shaped bodies. They are spread upto almost 1,000 kms in diameter. Most of them orbit the Sun in the asteroid belt, which lies between the orbits of Mars and Jupiter.
2.What are binary asteroids?
They are asteroids that travel in pairs, spinning around a common centre of gravity. This surprised astronomers, because they thought that the asteroids’ gravity would be too weak to bind them together. This discovery solved the age- old mystery of why impact craters often appear in pairs on Earth, such as the Clearwater Lakes in Canada.
3.Which is the largest asteroid in the Solar System?
The largest known asteroid is Ceres. Located in the asteroid belt, it is around
950 kilometres wide. Astronomers believe that water in form of ice may be buried under Ceres’ crust because they have found evidence of wafer-bearing minerals on the asteroid’s dust-covered surface.
Space And Universe
1.What are comets?
Comets are balls of snow which are found in the outermost part of the Solar System. The comet’s head consists of a nucleus, which is made up of dust and ice. It is known as Coma. The comet also has a tail. A comet is only visible when it comes near the Sun, because only then its ice melts and turns to gas, thereby releasing dust. This dust mixes with the atmosphere and forms a cloud, which is visible in the presence of sunlight.
2.What do you know about the tails of the Comets?
Another misconception about comets is that, as they move through space a tail follows behind. In fact, the tail is caused by the solar winds, so it always points away from the Sun. This means that as the comet moves away from the Sun the Halley’s Comet tail is pushed out in front of it.
Space And Universe
Meteorites Meteoroids And Meteors
1.What are meteorites?
Small pieces of space debris (usually parts of comets or asteroids) that are on a collision course with the Earth are called meteorites. There are three major types of meteorites – stone meteorites, iron meteorites and stony-iron meteorites.
2.What is the difference between a meteoroid and a meteorite?
As long as they are moving through space, these astronomical objects are called meteoroids. Meteoroids that all on Earth or other celestial bodies are called meteorites.
3.How high up do meteors occur?
Most meteors occur in the region of the atmosphere called the thermosphere. This “meteoric region” lies between about 80 km and 120 km (50 lo 75 miles) in altitude. This is a general guideline only, since very last meteors may first become visible above this height, and slow, bright meteors may penetrate below this region.
4.What is a meteor Shower?
A meteor shower is observed when the Earth passes through the orbit of a comet. When this occurs, small comet debris, ‘no larger than grains of sand enter the Earth’s atmosphere and get burned up. This result in streaks of light that can be observed in the night sky.
5.What is a shooting star?
A shooting star looks like stars that quickly shoot across the sky,
but it is really a small piece of rock or dust that hits the Earth’s atmosphere from space. It moves so fast that it heats up and glows as it moves through the atmosphere. Shooting stars are actually meteors. Most meteors burn up in the atmosphere before they reach the ground. However, once in a while a meteor is large enough that some of it survives and reaches Earth’s surface. Then it is called a meteorite.
Space And Universe
Asteroid And Kuiper Belt
1.What is Asteroid Belt?
The region between the orbits of Mars and Jupiter is known as the Asteroid Belt. This belt has many asteroids and minor planets. The smallest dwarf planet, Ceres, is the largest and the most massive object of this belt, as it makes up for 32% of the total mass of this belt. The two biggest asteroids Pallas and Vesta also lie in this Belt and along with Ceres and Hygiea, the third biggest comet, it forms more than 50% of the mass of this belt. It is at a distance around 2.06 AU from the Sun.
2.What is Kuiper Belt?
The region of Solar System beyond the orbit of Neptune, which is around 30 AU, to about 55 AU is known as Kuiper Belt. It is similar to the Asteroid Belt as it also contains many small bodies, though it is about Quo 20 times wider and 200 times more massive. While Asteroid Belt consists of objects made up of rock and metal, this belt consists of objects made of methane, ammonia and water. Three dwarf planets – Pluto (largest), Hanumea and Makemake lie in this belt.
Space And Universe
Scattered Disc And Oort Cloud
1.What is Scattered Disc?
Scattered disc is another region of our Solar System. It consists, of mainly minor planets which are made up of ice. The perihelia of Scattered Disc objects are more than 30AU and aphelia could be well over 100 AU. The inner boundary of Scattered Disc overlaps with Kuiper Belt. The dwarf planet Eris and the trans-Neptunian object 90377 Sedna lie in scattered disc.
2.What is Oort cloud?
Oort cloud is a hypothetical cloud which is around 1 light year or about 50,000 AU away. It is a cloud of comets and is situated at about 1/4th of the distance to Proximo Centauri, Sun’s nearest star. The outer extent of Oort cloud is believed to be the extent of Sun’s gravitational pull. All the long-period comets e believed to be a part of Oort cloud.
Space And Universe
1.What does NASA stand for?
NASA stands for National Aeronautics and Space Administration. It was set up on July 29, 1958. NASA’s John F Kennedy Space station has helped to set stage for America’s exploration for space. Most of the space missions you have heard about are probably NASA missions.
2.What is the International Space Station?
The International Space Station is a large spacecraft that orbits around Earth. The space station is also a science lab. Many countries worked together to build it. The space station is made of many pieces. The pieces were put together in space by astronauts. The space station’s orbit is about 220 miles above Earth. The first piece of the International Space Station was launched in 1998. A Russian rocket launched that piece. After that, more pieces were added. Two years later, the station was ready for people.
Space And Universe
WHICH WAS THE FIRST SATELLITE LAUNCHED BY INDIA?
The first satellite launched by India was Aryabhatta. It was named after the great Indian astronomer of the same name. Aryabhatta weighed 360kg and was launched by the Soviet Union on April 19, 1975 from Kapustin Yar using a Cosmos-3M launch vehicle. Aryabhata was built by the Indian Space Research Organization (ISRO) to conduct experiments related to astronomy. The satellite had the following objectives: To indigenously design and Fabricate a space-worthy satellite system and evaluate its performance in orbit. To evolve the methodology of conducting a series of complex operations on the satellite in its orbital phase. To set up ground-based receiving, transmitting and tracking systems. To establish infrastructure for the fabrication of spacecraft systems. Aryabhatia carried out experiments related to X-Ray Astronomy, Solar Physics and Aeronomy. The satellite re-entered the Earth’s atmosphere on 11 February 1992.
Space And Universe
WHICH ARE THE FARTHEST VISIBLE OBJECTS ?
The farthest visible objects in the Universe are the bright and powers quasars. They are the most intense sources of light in the Universe They are the most distant known objects, the nearest is billions of light years away. Although they are not bigger than the Solar System yet they glow with the brightness of a 100 galaxies. 3C273, which is 2 billion light years away, is the brightest quosar. Quasars are at the heart of galaxies called active galaxies. Astronomers believe that a huge black hole lies at the core of quasars. As it draws in matter, the black hole ejects vast amounts of energy. The black hole in a quasar may draw in matter with the same mass as 100 million suns. Being so small and far away, they can still be n seen because the powerful burst of radiation which it gives out, makes them the brightest objects in the Universe.
Space And Universe
WHICH PLANET HAS A BLUE-GREEN COLOUR?
Uranus is made up of gas and liquid.Hydrogen, helium and methane make up the outer layers of the planet. It is methane which gives Uranus its blue-green colour. When viewed from a telescope, it looks like a faint blue-green disc. Uranus is the third largesi planet in the Solar System with a diameter of 51,118 km and a mass 14.54 times that of the Earth. This planet was discovered by William Herschel in 1781. When he discovered the new planet, he wanted to name it George, after the English King George III. Finally, it was named Uranus after Urania, the ancient Greek goddess of astronomy Uranus has about 20 moons and al are named after characters from William Shakespeare’s plays. Among them the five large ones are Ariel Umbriel, Titania, Oberon and Miranda. A day on Uranus lasts for 17 hours and 14 minutes and its year takes 84 Earth years.
Space And Universe
WHICH IS THE BIGGEST PLANET IN THE SOLAR SYSTEM?
Jupiter is the big.gest planet in the Solar System. It’s 1,300 times big ger than the Earth Besides, it is twice os heavy as all the planets put together. It is also known as the gas giant because about 90% of it isv gene made of gases Thydrogen and helium. At the centre is a small, rocky core which is as big as the Earth. Such a vhuge plonel might spin slowly, but Jupiter spins incredibly fast. It completes its day in ten hours. At the equator, the speed of rotation is 45,259.5 km/hr, which is more than 25 times faster than the Earth. The average distance of Jupiter from the Sun is 778.33 million km. It takes it 11 years and 315 days to make one orbit. This gigantic planet is 142,984 km in diameter. Jupiter has around 61 moons and more are still being discovered. The largest moons are lo Europa, Callisto and Ganymede. lo has constant volcanic eruptions Powerful winds dominate the atmosphere of Jupiter with criss crossing jet streams, lightning and huge hurricane-like storms like the Great Red Spot. This storm has been raging for over 300 years and is about 2 Earth diameters wide.
space and universe
WHICH IS THE HOTTEST PLANET?
With a surface temperature of over 470 degrees C, Venus is the hottest planet in the Solar System. Venus is covered in a thick cloud of carbon dioxide which acts like a blanket, stopping most of the Sun’s heat from getting away. That is why Venus is so hot. Venus is named after the Roman goddess of beauty. It is almost the same size as the Earth. It is at a distance of 42 million km from it. The pressure on the surface of Venus is 90 times greater than that on the Earth. It is similar to being underwater on the Earth at a depth of 914 m. Large clouds within the atmosphere rain sulphuric acid onto the planet’s surface. Scientists believe that if it were possible to land on Venus, the sky would appear gloomy orange in colour. Venus and Mercury are the only two planets in the Solar System that do not have moons orbiting them. A year on Venus is shorter than its day. It takes the planet longer to turn on its axis than it takes it to orbit the Sun. The slow rotation means that atmosphere does not have a force to spin it off into space.
Space And Universe
WHICH PLANET IS CLOSEST TO THE SUN?
Only at a distance of 60 million km from the Sun, Mercury isv closest to the Sun. Mercury looks very much like the Moon It has a wrinkled surface which may have been due to the cooling of iron ore that caused the planet to shrink. The surface of this planet has many craters. Scientists believe that these craters were formed 4 million years ago by the debris left over from the birth of the Solar System which crashed into the planet. The temperature on Mercury varies from 180 degrees C at night to over 430 degrees C during the day. Mercury being so close to the Sun becomes the fastest orbiting planet. It completes its revolution in just 88 days, i.e. a year on Mercury lasts for 88 days with a speed of 173,000 km/hr. But it rotates very slowly; it takes 59 Earth days to make a day. Mercury has been visited by only one spacecraft, Mariner 10. It flew by three times in 1973 and 1974. Only 45% of the surface was mapped. Unfortunately, it is too close to the Sun to be safely imaged by the Hubble Space Telescope
Space And Universe
WHICH PLANET IS ALSO CALLED THE “RED PLANET’?
Mars, the fourth planet from the Sun, is also called the ‘Red Planet’When we look at Mors in the night sky, it appears pale red in colour The planet looks rusty red because its surface is covered with rocks and sand which contain a lot of iron. This iron has rusted over the years, giving the whole planet its rusty red colour. Mars is about half the size of the Earth with a diameter of 6,787 km. It orbits around the Sun in 687 days and spins around once in 24.62 hours almost the same as the Earth takes to rotate. The surface of Mars is cracked by a valley called the Valles Mariners. It is 4,000 km long and 5-10 km deep, making it the largest canyon in the Solar System. Phobos and Deimos are iwo irregular shaped moons of Mars. They may have once been asteroids which were caught in the planet’s gravity. Phobos and Deimos were discovered in 1877 by an astronomer Asaph Hall Phobos is 27 km across whereas Deimos is just 15 km across.
Space And Universe
WHICH ROBOT EXPLORED MARS?
All spacecraft do not carry people.Satellites and space probes are spacecraft that travel without people.Some of these satellites are used to study space whereas others are used to carry phone messsages and television pictures around the world. Space probes are robots controlled by compulers on the Earth. The first of these were the Lunokhod robot rovers which landed on the Moon in 1970 and 1973. The US Pathfinder probe reached Mars on 4th July 1977 Sojourner was the wheeled robot GY vehicle which explored the surrounded oreo. Pathfinder and Sojourner operated for 83 days and took more than 16,000 photographs and stunning images of the surface of the ‘Red Planet’. Sojourner was very successful in navigating its own way around the surface on its six wheels analyzing rock and soil samples and relaying the information to Pathfinder which sent it back to the Earth.a
space and universe
WHICH SPACECRAFT FLEW THE FARTHEST?
Voyager 2, launched on 20th August 1977 from Cape Canaveral, Florida,aboard a Titan-Centaur rocket, has flown the farthest, Voyager 2 achieved the Grand Tour of our outer solar system, taking advantage of a rare planetary alignment to visit the four giant outer planets – Jupiter, Saturn, Uranus and Neptune, a feat not likely to be repeated in a person’s lifetime. The primary mission of Voyager 2 was to be a backup for Voyager 1 in case anything should prevent it from completing its mission, or in case Voyager 1 made some fantastic discovery. Voyager 2 has flown past Jupiter, Saturn, Uranus and Neptune. Now, it is beyond our Solar System heading into interstellar space. Until the successful Voyager 2 mission, our knowledge about these planets was very faint. Voyager 2 journeyed through Jupiter in 1979, Saturn in 1981, Uranus in 1986 and Neptune in 1989. It discovered six moons of Neptune and nine moons of Uranus. It also mapped details about the rings around Uranus and the fierce winds of Neptune. The rings of Uranus were first found in 1977 but Voyager 2 detected a total of 11 rings made of very dark rocks and a little ice dust.which were
Space And Universe
WHICH IS THE LARGEST TELESCOPE IN THE WORLD?
objects by using lenses and mirrors to Optical telescopes magnify distante bend light rays so that they may focus Refracting telescopes are optical telescopes that use lenses to refrac (bend) the light rays. Reflecting telescopes are optical felescopes that refract light rays by reflecting them off curved mirrors. In 1688, reflecting telescopes were used for the first time. Now, they comprise all the world’s largest telescopes. The world’s largest optical/infrared telescopes are the twin 10-metre Keck Telescopes operated by the University of California and Caltech on the 13,700ft dormant volcano, Mauna Kea, Hawaii. The Keck Telescopes employ hexagonal segmented primary mirrors, each made out of 36 hexagonal segments, 1.8m in diameter. In order to maintain a precise optical surface, the positions of the segments are monitored by sensors which relay signals to o computer. The computer drives precision actuators, keeping each segment in proper alignment.
Space And Universe
WHICH GALAXIES ARE VISIBLE TO THE NAKED EYE FROM THE EARTH?
Galaxies are giant collections of million or trillions of stars held together by gravity.Our own local galaxy is the Milky Way. It was Edwin Hubble who proved that other galaxies existed beyond the Milky Way. More than half of all the galaxies are elliptical (round or oval) in shape. The other common shapes are spiral galaxies like our Milky Way, barred spirals and rregular galaxies. Besides the Milky Way, three other galaxies are visible to the naked eye from the Earth. They are Small and Large Magellanic Clouds and the Andromeda galaxy. The Small Magellanic Cloud be the debris of mighty collisions between galaxies. They are small irregular galaxies that orbit the Milky Way once every 1.5 billion years. The Andromeda galaxy is nearest to ours. It is about 2-3 million light years away and is the farthest object visible to the human eye.
Space And Universe
WHICH IS THE COLDEST PLANET?
Pluto is the coldest planet of all because it is the farthest from the Sun. Another reason for this is the thick layer of ice over its surface. The inside is alsomade of ice and rock. It is always cold and dark on Pluto even in the middle of the day. This is due to the fact that the Sun appears 1,000 times fainter from the surface of Pluto than it does from the Earth. During summer, the surface warms up sufficiently to melt some of its ice turning it to gas, which causes a slight atmosphere. As Pluto moves away from the Sun, the gas freezes and converts into ich once again. Pluto has one moon, Charon, which is not much smaller than Pluto itself. No other moon is as close to the size of its planet o Charon is to Pluto. The journey of Pluto around the Sun takes 248 Earth years. This means that, since its discovery in 1930, it still has 177 years to go until it has made a complete orbi around the Sun. Pluto is the only plane in the Solar System which has not been visited by a space probe. elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.
space and universe
WHICH PLANET IS CALLED THE ‘EVENING STAR?
Planets do not make their own light; they reflect the Sun’s light, Venus shines like a star in the night sky because its thick atmosphere reflecis sunlight amazingly well. After the Sun and the Moon, this planet is the brightest thing in the sky. It is also called the ‘Evening Star because it can be seen rom the Earth just before sunset in the evening. It is also called the “Morning Star’ when it appears in the east at sunrise. A day is the amount of time a planet takes to spin on its axis and a year is the time taken to travel around the Sun. Venus spins very slowly on its axis but orbits around the Sun more quickly than the Earth. A day on Venus lasts for 243 Earth days, but a year is only 225 Earth days. The cloudy atmosphere of Venus makes it difficult to study it from the Earth. Hence, most of the information obtained is through the use of space probes. Radar mapping of the planet shows lots of craters. Moreover, 90% of the landforms are volcanic, LOGY
WHICH STARS ARE NEAREST TO US?
Today, because of the progress in science, We con measure of distance. For measuring the vast distances in the Universe, o specie unit of measurement is sel which is known as light year. A light yeon simply the distance a ray of light travels in a year Light travels obou 186,000 miles in a second, Therefore, in one year, it will travel o distance of about 6,000,000,000,000, les trillion miles. The sun, oto distance of about 92 million miles, is the closest stor to the Earth. After the sun, the closes star to us is the Proximo Centauri, which is about four and one-third light years away. It means a distance of 26 billion miles. This star is visible from the Southern Hemisphere. The closest star from the Northern Hemisphere is Sirius. It is eight light years away. The farthest star that we can detect with the naked eye is about 8,000,000 light years away With the help of telescopes, we are able to see stars that are about six thousand million miles away.?
WHICH IS THE NATURAL SATELLITE OF THE EARTH?
Satellites ora objects thal orbit planets and other space objects. There are two types of satellites natural and artificial. Moons are natural satellites. Spacecraft sent up to orbit the Earth and the Sun are artificial satellites. The Moon revolves around the Earth while the Earth revolves around the Sun. The Moon is composed of rock. It resembles a small planet. It is just over a quarter of the Earth’s size. It takes the Moon about one month to revolve around the Earth. During that time, its shape changes from a thin crescent to a Full Moon and back again. The Moon does not emit any light of its own. It reflects some of the sunlight that falls on it. The Moon has no atmosphere. It is through atmosphere that light is dispersed (spread) and sound waves travel (light waves and sound waves bounce off tiny particles in an atmosphere). This means that no sound can be heard on the Moon. The sky is always black because ight cannot be spread, unlike on the Earth where light spreads to give the sky a blue colour.
WHICH ARE THE TWELVE SIGNS OF THE ZODIAC?
Constations are paiems of stars that hele astronomers locate stars among the thousands in the night sky Original a constellation wes regarded as stor system. Now it refers to an area of the sky. The idea it constellation is confusing. So, astronomers use the term celestial sphen meaning on inaginany sphere surrounding the Earth with all the site ünside. The zodiac is a band of 12 constellations which na right round the celestial sphere. The Moon mm the Sun and all the other planets except Pluto travel across the sky within this band of stars. The Sun appears to spend about month in each constellation of the zodiac The Ancient Greeks divided the zodiac into 12 parts. These are called the signs of the zodiac. The 12 constellations of the zodiac are Anes,Taurus, Gemini, Cancer, Leo, Virgo Libra, Scorpio, Sagittarius, Capricom Aquarius and Pisces.
space and universe
WHICH WAS THE FIRST COMMERCIAL SATELLITE USED?
Telstar was the first active communications satellite launched on 10th July, 1962, from Cape Canaveral. It was the first satellite designed to transmit telephone and high-speed data communications. Telstar 1 was capable of actively transmitting signals and was used for both telephone and television systems. The first broadcast, which was relayed from the United States to England, showed an American flag flapping in the breeze. Telstar was placed in an elliptical orbit (completed once every 2 hours and 37 minutes), revolving at a 45 degree angle above the equator. Its shape was a faceted sphere with a diameter of a little over 34 inches. Telstar was equipped with a helical antenna which received microwave signals from a ground station. Then, it amplified and rebroadcast the signal. The broadcasts were made from a series of somewhat directional feed horns distributed around the equator of the satellite. The electronics switched which antenna was active as the satellite rotated. 10-14 ?
WHICH WAS NASA’S FIRST COMMUNICATIONS SATELLITE?
NASA’s first communication satellite was Echo Ill was put wil orbit on 12th August 1960. The was made of 0.127 mm (0.005
polyester film Echo I was 30,5 metres (100 feel) bolo inch) thick metallized Mylo successfully used to redirect transcontinental and inter:
continental telephone, radio and television signals. The satellite also aided the calculation of atmospheric density and solar pressure due to its large area-to-mass
ratio. As its shiny surface was also reflective in the range of visible light Echo I was visible to the unaided eye over most of the Earth. Brighter
than most stors, it was probably seen by more people than any other man-made object in space. Once in orbit, residual air inside the
balloon expanded, and the balloon began its task of reflecting radio transmissions from one ground station back to another. It worked by
reflecting signals back to the Earth, rather than actively transmitting them. Echo 1 remained in service until 1968 and its successor, Echo 2
functioned from 1964 to 1969
WHEN WERE THE FIRST RINGS OF SATURN OBSERVED?
The rings of Saturn are one of the wonders of the Solar System. In the year 1610, Galileo observed something strange about Saturn. But his telescope was weak and he thought Saturn was a triple planet. Finally, in 1655, Christian Huygens confirmed the existence of the now familiar rings of Saturn.NASA’s Voyager 1 and 2 missions imaged the ring system extensively in 1980 and 1981. The rings have been given letter names in the order of their discoveries. The main rings are, working outwards from the planet, known as C, B and A. The ‘Cassini Division is the largest gap in the rings and separates Rings B and A (named after Jean-Domenique Cassini who discovered the gap in 1676). Over 10,000 separate rings have been identified. The rings look solid but they are made up of millions of chunks of ice and rock arranged in bands of different densities. Scientists believe that these may be the remains of a shattered moon or comet. The rings measure about 270,000 km across but are just 100m to 1km thick.
WHEN WAS MARS EXPLORED?
All spacecraft do not carry people. Satellites and space probes are spacecraft that travel without people. Some of these satellites are used to study space whereas others are used to carry phone messages and television pictures around the world. Space probes are robots controlled by computers on the Earth. The first of these were the Lunokhod robot rovers which landed on the Moon in 1970 and 1973. The US Pathfinder probe reached Mars on 4th July, 1977. Sojourner was the wheeled robot vehicle which explored the surrounded area. Pathfinder and Sojourner operated for 83 days and took more than 16,000 photographs and stunning images of the surface of the ‘Red Planet.Sojourner was very successful in navigating its own way around the surface on its six wheels analyzing rock and soil samples and relaying the information to the Pathfinder which sentit back to the Earth.
space and universe
WHEN WERE THE MOONS OF JUPITER DISCOVERED?
The four biggest moonsof Jupiter lo, Europa,Callisto and Ganymede were discovered by Galileo in 1610. They are also called Jupiter’s Galilean moons. Ganymede is the largest moon of the Solar System. It is 5,276 km across and is bigger than Mercury and Pluto. It looks hard. Under its shell of solid ice, there is 900 km of slushy, half melted ice and water Callisto is the second biggest moon of Jupiter with a diameter of 4,806 km. Almost every bit of this moon is covered in craters. lo is the third biggest and closest moon of Jupiter. Its surface is a mass of active volcanoes. Because of the emission of sulphur, lo is orange and yellow in colour. With a diameter of 3,138 km, Europa is the smallest of the Galilean moons. It is covered by a thick crust of ice which looks smooth like frozen water, but a close-up view of the surface reveals numerous cracks.
WHEN DID THE FIRST WOMAN GO INTO SPACE?
Valentina V. Tereshkova (1937), a cosmonaut from the former Soviet Union, became the first woman in space on 16th June, 1963. In 1959 Tereshkova joined the Yaroslavl Air Sports Club and became a skilled amateur parachutist. Inspired by the flight of Yuri Gagarin, the first man in space, she volunteered for the Soviet space programme. Although she had no experience as a pilot, her 126-jump record gained her a position as a cosmonaut in 1961. Four candidates were chosen for a one-time woman in-space flight; Tereshkova received an Air Force commission and trained for 18 months beforebecoming the chief pilot of the Vostok VI. She orbited the Earth 48 times over the course of three days, aboard the Vostok 6. The flight lasted for 2.95 days (=70.8 hours). On her return from space, Tereshkova received a warm welcome and embarked on o world-speaking tour. At present, Tereshkova holds the chair of the Russian Association of International Co-operation.
WHEN DID THE FIRST ELECTRIC TRAIN APPEAR?
An electric locomotive is a locomotive powered by electricity from an external source. The first known electric locomotive was built by a Scotsman, Robert Davidson of Aberdeen, in 1837, and was powered by galvanic cells (batteries). Davidson, later, built a larger locomotive named Galvani which was exhibited at the Royal Scottish Society of Arts Exhibition in 1841. The first electric passenger train was presented at Berlin in 1879. However, the limited electric power available from batteries prevented its general use on railways. It was designed by the German scientist Werner von Siemens. It was shown at an international trade exhibition in Berlin in 1879. One of the earliest electric railways in England was Volk’s Electric Railway, built along the sea-front at Brighton. This railway was opened in 1883. The first electric trains to be used as a serious means of transport appeared on the London Underground in 1890. The manufacturing of longer distance electric railway began after the FirstWorld War.
WHEN WERE THE MMU’S INVENTED?
The first person in space was a Russian cosmonaut Yuri Gagarin on April 1961. He made a single orbit in his spacecraft Vostok 1 and then parachuted safely back to the Earth. The short journey was seen as a challenge by the Americans. In 1965, a Russian Aleksei Leonov made the first space-walk but he had to remain attached to his spacecraft. Then, in the early 1980’s, scientists developed the Manned Manoeuvred Unit (MMU) which is a backpack featuring jet thruster that allows astronauts to move freely in space. The first free space-walk took place from the American Challenger in 1984. Earlier, spacecraft used rocket power to blast them into space after which the rocket had fallen to the Earth. Then, the Americans came up with the idea of re-usable spacecraft. This was called a space shuttle. Columbia was the first space shuttle which took off in 1981.
space and universe
WHEN WERE THE FIRST LIVING CREATURES SENT INTO ORBIT?
Laiko, a breed of dog, was a Russian space dog which became the first recorded living creature from the Earth to enter orbit. After undergoing training with two other dogs, she was selected to be the occupant of the Soviet spacecraft Sputnik 2 and was launched into space on 3rd November, 1957. Laika sat in a pressurized compartment within a capsule that weighed 1,103 pounds (500 kilograms). Laika died a few hours after launch from stress and overheating, probably due to a malfunction in the thermal control system. Although Laika could not survive the trip yet the experiment proved that a living passenger could survive, being launched into orbit and endure weightlessness. It paved the way for human spaceflight and provided scientists with some of the first data on how living organisms react to spaceflight environments. This event followed the successful Soviet launch on 4th October, 1957, of Sputnik 1, the first human made satellite ever placed in orbit.
WHEN WAS OUR CLOSEST GALAXY DISCOVERED?
An international team of astronomers have discovered a new galaxy colliding with our own Milky Way. This new galaxy, Canis Major, is located only 42,000 light away from the centre of the Milky Way – it’s our new “closest galaxy”. Also, the Canis Major dwarf galaxy after the constellation in which it lies, is about 25,000 light years away from the solar system. Canis Major was discovered during an infra-red survey of the sky, which allowed the astronomers to peer through the obscuring dust and gas of the Milky Way. The discovery team noticed an over density of M giants, red-giant stars that are bright at infra-red wavelengths, at a distance of about 25,000 light years in the general area of Canis Major. Canis Major is quite small; it only contains about a billion stars The Canis Major dwarf went undetected until now for two reasons. Firstly, at visible wavelengths, it is largely hidden behind gas and dust near the plane of the Milky Way Secondly, it is quite sparse, with its starsappearing mixed together with theirMilky Way counterparts.
WHEN WERE THE RINGS OF VARIOUS PLANETS DISCOVERED?
All the giant planets in our solar system have rings: Jupiter, Saturn, Uranus and Neptune. Jupiter’s ring is thin and dark and cannot be seen from the Earth. Jupiter’s rings were discovered by the inter planetary space probe Voyager 1 in March 1979. The rings extend 1,29,130 kilometres from the centre of the planet. They are about 7,000 kilometres wide and less than 30 kilometres thick. A faint inner ring is believed to extend to the edge of Jupiter’s atmosphere Saturn has the largest, most spec tacular set of rings in the solar system. Saturn’s rings were first recognized by a Dutch astronomer, Christiaan Huygens, in 1659. They were examined in detail by the Voyager I and Voyager 2 missions in 1980 and 1981 respectively. Saturn’s rings are about 66,400 kilometres wide and 2,73,200 kilometres in diameter, but less than 100m to 1km thick. The rings are made of dusty ice in the sizes of boulders and smaller chunks that gently collide with one another as they orbit around Saturn. Uranus has nine dark rings around it, whereas Neptune’s rings are also dark, but contain a few bright arcs.
WHEN DO WE SEE THE DIFFERENT PHASES OF THE MOON?
As the Moon circles the Earth, different amounts of the illuminated part of the Moon are facing us. There are eight distinct phases of the Moon:
New Moon – When the Moon is roughly in some direction as the Sun, its illuminated half is facing away from the Earth and therefore, the part that faces us is all dark: we have the New Moon.
Waxing Crescent Moon – As the Moon moves around the Earth, we get to see more and more of the illuminated half. This phase is called the Crescent Moon.
Quarter Moon – A week after the New Moon, when the Moon has completed about a quarter of its turn around the Earth, we can see half of the illuminated part. This is the First Quarter Phase.
Waxing Gibbous Moon – During the next week, we keep seeing more andmore of the illuminated part of the Moon. It is now called Waxing Gibbous.
Full Moon – Two weeks after the New Moon, the Moon is now halfway through its revolution so that we may see a full disc; we have a Full Moon.
Waning Gibbous Moon – From now on, until it becomes new again, the illuminated part of the Moon that we can see decreases. This is called Waning Gibbous.
Last Quarter Moon Three weeks after the New Moon, we – again can see half of the illuminated part. This is usually called Last Quarter.
Waning Crescent Moon – Finally, during the fourth week, the Moon is reduced to a thin sliver are, sometimes called Waning Crescent.
space and universe
WHEN WAS NICOLAUS COPERNICUS THEORY PROVED CORRECT?
Nicolaus Copernicus was born on 19th February, 1473, at Torun in Poland and died on 24th May, 1543. He was the first astronomer who suggested that the Sun was the centre and the Earth went around the Sun. This is called the heliocentric view. Copernicus described his views in a book called ‘De revolutionibus orbium coelestium (On the Revolutions of the Heavenly Spheres). But the Roman Catholic Church banned his book for almost 300 years. Because, until then, most people thought that the Earth was the centre of the Universe and everything – the Moon, the Sun, planets and stars – revolved around it. Copernicus’ ideas came from studying ancient astronomy and also from the way planets seemed to perform a backward loop through the sky. Copernicus theory proved to be correct only in 1609, when Galileo saw moons revolving around Jupiter through his telescope
WHEN DID WILLIAM HERSCHEL DISCOVER URANUS?
William Herschel (1738-1822) was an astronomer who built a very powerful telescope in his home in Bath, England. Until his time astronomers believed that there were just seven independent objects in the sky – the Moon, the Sun, and five planets (Mercury, Venus, Mars, Jupiter and Saturn). The sixth planet Uranus was discovered by Herschel in 1781. At first, when Herschel looked through his telescope, he saw a dot of light, which he thought to be a star. When he looked more closely, he saw a tiny disc instead of a point of light. The next night when he looked, the star had moved, which meant that it had to be a planet. Herschel wanted to name the planet George, after King George III, but, finally, the name ‘Uranus was chosen. Later, he alsoidentified two of the moons of Uranus and Saturn. William’s sister Caroline, another great astronomer, assisted him in his discoveries. Caroline listed all the stars of the northern hemisphere.
WHEN WAS THE VERY FIRST LIQUID FUEL ROCKET LAUNCHED?
For hundreds of years, man knew about the solid, gunpowder-type rockets. After 17 years of theoretical and experimental work, Dr Robert H.Goddard, finally, achieved the flight of a liquid fuelled rocket on 16th March, 1926. A liquid fuel required a continuous source of oxidizer to be able to burn at a rate capable of producing the rocket thrust as desired. A means for combining the fuel and the oxidizer at the proper rates in the combustion chamber had to be developed. The high pressures created by combustion required thot the fuel and oxidizer be injected into the chamber under even a higher pressure. After a number of design attempts, Dr Goddard, finally, chose gasoline as the fuel and liquid oxygen (lox) as the oxidizer. After 2.5 seconds of flight, the fuel was expended, the roar ceased abruptly and the rocket fell to the earth 184 feet away. It C had reached an estimated speed of 60 miles per hour and the height of 41 feet.
WHEN WAS THE FIRST PULSAR DETECTED?
A pulsar is a neutron star that spins rapidly, beaming out regular pulses of radio waves. The first pulsar was discovered by chance by Jocelyn Bell and Anthony Hewish in 1967 whowere actually studying distant galaxies at the time. Jocelyn Bell noticed small pulses of radiation when their telescope was looking at a particular position in the sky. For a short time, scientists thought they might be coming from an extra-terrestrial civilisation. In fact, the source of these pulses was initially referred to as LGMI, Little Green Man 1. Once established that the signals were not of this origin the unidentified object, they were coming from wascalled a “pulsar” because the emission was pulsed. Pulsar astronomers have now detected over 1,500 pulsars and expect to discover thousands more during the next few years. More than two-thirds of the currently known pulsars were discovered using the Parkes radio telescope.
space and universe
WHEN DOES A SUPERNOVA HAPPEN?
A supernova is the final, gigantic explosion of a supergiant star at the end of its life. A supernova can happen in two ways, firstly, a star has enough mass. When burning ends, the radiation pressure suddenly stops and gravity causes the star to collapse into a hard neutron dense core, then it bounces out. Secondly, it is also possible that a star with much less than the necessary mass burns out and becomes a white dwarf. Then, this white dwarf gains some mass to tip it over the edge, which then causes sudden huge fusion. This is so big that the star will totally explode in a supernova. A supernova lasts for just a week or so, but shines as bright as a galaxy of 100 billion ordinary ILLUSTRATION LICK CHANDRA stars. Although many supernovae have been seen in nearby galaxies yet supernova explosions are relatively rare events in our own Galaxy, happening once a century or so on an average. The last nearby supernova explosion occurred in 1680.
WHEN WILL THE SUN DIE?
The Sun is about 4.5 billion years old and it is estimated to still possess a 5-billion-year supply of hydrogen (hydrogen is the fuel that drives nuclear fusion on the Sun). Therefore, it is predicted that the Sun will die in approximately 5 billion years. Once the Sun has converted all its hydrogen into helium, the Sun will change from its current form, a yellow dwarf, into a red giant. After this phase, the outer layers of the Sun will continue to expand. As this happens, the core will contract; the helium atoms in the core will fuse together, forming carbon atoms and releasing energy.The core will, then, be stable since the carbon atoms are not further compressible. Then, the outer layers of the Sun drift off into space, forming a planetary nebula (a planetary nebula has nothing to do with planets) exposing the core. Most of its mass will go to the nebula. The remaining Sun will cool and shrink; it will eventually be only a few thousandmiles indiameter.
WHEN DID PEOPLE FIRST START STUDYING THE STARS?
People might have been gazing into space for stars for millions of years. But they probably began studying the night sky seriously only about 5,000 years ago. Early civilizations in the Middle East left records of their observations. The Babylonians were skilled observers; the Egyptians were good observers. The Egyptians lined up their pyramids with certain constellations or star patterns. Stonehenge was built around 2,800 BC in Britain, possibly as a kind of observatory. Stones were lined up to show the positions of the Sun and the Moon at different seasons. Ancient Chinese and Mayan astronomers left accurate records of their observations. Nowadays, astronomers observe the stars from observatories. The great domes on these observatories house big telescopes which use curved mirrors to collect the light from the stars. Most observatories are built on mountains, above the thickest part of the atmosphere, where the air is cleaner and clearer.
WHEN WAS NASA ESTABLISHED?
NASA (National Aeronautics and Space Administration) is an agency of the United States government, responsible for the nation’s public space program. NASA was established on 29th July, 1958, by the National Aeronautics and Space Act. NASA is based in Washington, D.C., and is under the guidance of the president of the United States.
NASA is responsible for developing space exploration. It conducts both human and unpiloted spaceflights, and also trains astronauts and carries out scientific experiments in space Its areas of space research include planetary science, astrophysics, astronomy, Earth science, astrobiology and aerospace medicine. The agency studies the performance and design of airplanes (aeronautics) and rockets as well. NASA is also an active participant in the construction and staffing of the International Space Station. The United States, Canada, Japan, Russia and the nine members of the European Space Agency (ESA) collaborate on this project. NASA has had many successful space missions and programs, including over 150 manned missions.