Dave Reneke's World Of SPACE & ASTRONOMY
Lots Of Tantalizing Tid-Bits' From the World of Astronomy and Space
1 Nearly every astronaut experiences some space sickness, caused by the wildly confusing information reaching their inner ears. In addition to nausea, symptoms include headaches and trouble locating your own limbs. Just like college, really.
2 And those are the least of your worries. In weightlessness, fluids shift upward, causing nasal congestion and a puffy face; bones lose calcium, forming kidney stones; and muscles atrophy, slowing the bowels and shrinking the heart.
3 At least you'll be puffy, constipated, and tall: The decreased pressure on the spine in zero-g causes most space travellers to grow about two inches.
4 Lab rats sent into space during mid-pregnancy, while their foetuses' inner ears are developing, spawn some seriously tipsy babies.
5 No humans have yet been conceived in space, so we can only imagine.
6 So that's what it takes: A 2001 study showed that astronauts who snored on Earth snoozed silently in space.
7 But astronauts sleep less soundly; 16 sunrises a day throws a major wrench into their circadian rhythms.
8 And Ziggy played guitar. At the start of the workday on the space shuttle, mission control in Houston broadcasts wake-up music, usually selected with a particular astronaut in mind. On the all-work, no-play International Space Station, crews wake to an alarm clock.
9 If you are ever exposed to the vacuum of space without a suit on, don't hold your breath: Sudden decompression would cause your lungs to rupture.
10 In addition, water on the tongue, in the nose, and in the eyes would boil away. This actually happened in 1965, when a space suit failed during a NASA experiment and the tester was exposed to a near vacuum for 15 seconds.
11 Contrary to Hollywood, though, you wouldn't explode. Lack of oxygen in the blood is what would kill you, but it would take about two minutes.
12 John Glenn found it hard to choke down his food, but not because of the lack of gravity: Early astronauts relied on aluminium tubes of semiliquid mush, food cubes, and dehydrated meals.
13 Today astronauts can spice up their meals with salt and pepper-in liquid form. Sprinkled grains would float away, tickling noses and clogging vents.
14 Missing something? Those vents on the space shuttle and International Space Station serve as the lost and found, sucking up anything that's floating about unsecured.
15 The shuttle commode requires that astronauts align themselves precisely in the dead centre of the seat. A mock-up of the shuttle toilet, complete with built-in camera, is used to train them how to position themselves.
16 NASA tried building a bathroom into its space suits-a fitted condom attached to a bladder for men, a moulded gynaecological insert for women-but gave up and passed out nappies (diapers) to all.
17 Returning astronauts report extreme difficulty moving their arms and legs right after touchdown, one reason why they call landing "the second birth."
18 But some long-duration cosmonauts report that the hardest thing to readjust to about life on Earth is that when you let go of objects, they fall.
19 Better just to stay up there? Eighteen people have died on space missions, but never in space-always on the way up or the way down.
More Amazing Facts
- Mars is the current focus for most planetary exploration. Mars' diameter about half that of the Earth and its atmosphere is very thin, about 1% as thick as Earth's. Because it is farther from the Sun, Mars is a cold and barren world. It has thin seasonal ice-caps and frequent planet wide dust storms. Mars has the tallest mountain in the Solar System -Olympus, an extinct volcano which is 400km wide at its base and three times higher than Mt Everest at its peak.
- Most life on Earth depends on the Sun for its survival. Our Sun's diameter is 1.4 million kilometres, compared to Earth's puny 12, 750km - but it is actually a small star as stars go. Astronomers classify it as a yellow dwarf star. Some stars are a hundred times bigger!
- Our Solar System is basically divided into two halves. The inner half includes Earth and Mars, which are known as the rocky planets, and are quite small, made of rock and have thin atmospheres or none to speak of, in the case of Mercury. The outer planets - Jupiter, Saturn, Uranus and Neptune are known as the Gas Giants, and are all huge and made mainly of gas. Pluto, on the outer extremity of the Solar System, is small and made of rock and ice.
- Our Milky Way Galaxy's diameter is about 100,000 light-years. This means that at the speed of light (300,000 kilometres per second), it would take 100,000 years to go from one side to the other! It contains somewhere between 100 billion and 400 billion stars
- Venus used to be called Earth's sister planet. Size aside, Venus is very unearth-like with an atmosphere of almost pure carbon dioxide, clouds of sulphuric acid droplets, and a temperature of 900 degrees Fahrenheit! The few Russian spacecraft that landed there lasted only a few hours before being baked and crushed! Venus rotates backward on its own axis. The rotation is so slow, that a Venusian day (243 Earth days) is longer than its year (224.7 Earth days)!
- Jupiter is the largest planet in the Solar System. Like the other Gas Giant planets (Saturn. Uranus and Neptune), it doesn't have a solid surface that we can see; rather, we see the tops of its complex atmospheric cloud system. The most prominent feature of Jupiter's atmosphere is the Great Red Spot -a huge red-coloured cyclone bigger than the Earth. Galileo first saw the Great Red Spot almost 400 years ago, so it has been going for at least that long if not more.
- Saturn is the planet with the famous rings. The planet is made mainly of gas with a hidden rocky core. Saturn's overall density is very low. If you had a body of water big enough to put it in, Saturn would float!
- Uranus & Neptune are" twin worlds" about four times the diameter of Earth. Their blue/green atmospheres are dominated by strong winds blowing at up to 2,000 kph -the fastest winds in the Solar System! Pluto is small and made entirely of ice. A spacecraft was launched in 2006 and will take about 10 years to get there.
- The Voyager 1 and 2 probes that visited the Gas Giant planets are still working and sending back basic data from deep space. They each carry an LP record made of gold-plated copper, containing sounds, pictures, music and messages from Earth. Maybe someday, someone will find these probes and find out all about us from these LP records!
- The closest star system to Earth is the Alpha Centauri system, about 4.2 light-years away. Alpha Centauri is actually a binary star system, made up of two stars very similar to our Sun. There is a third, much smaller star, called Proxima Centauri in the same vicinity.
- Scientists believe that a giant black hole lives at the core of our galaxy. It is estimated to weigh millions of times more than our Sun. But that's nothing -some other galaxies have central black holes that weigh billions of times more than our Sun!
- A big question of modern physics is what will be the eventual fate of the Universe? Will it keep expanding forever, or will it eventually stop, or will it start to re-collapse, leading to the opposite of the Big Bang? Most research indicates that the Universe will not only expand forever, but it will get faster and faster with time.
- On a clear night, the human eye can see between 2,000 and 3,000 stars in the sky. The farthest you can see with the naked eye is 2.4 million light years away! That's the distance to the giant Andromeda Galaxy.
- Most astronomers believe the Moon was formed when an asteroid almost the size of Mars hit Earth and shot debris into orbit.
- Astronauts are a little taller in space than on Earth. There is less gravity in space, so their bones are not as squashed together as they are on Earth.
125 More Amazing Facts about Space, Planets and Universe
1. Saturn's moon Titan has plenty of evidence of organic (life) chemicals in its atmosphere.
2. Life is known to exist only on Earth, but in 1986 NASA found what they thought might be fossils of microscopic living things in a rock from Mars.
3. Most scientists say life's basic chemicals formed on the Earth. The astronomer Fred Hoyle said they came from space.
4. Oxygen is circulated around the helmet in space suits in order to prevent the visor from misting.
5. The middle layers of space suits are blown up like a balloon to press against the astronaut's body. Without this pressure, the astronaut's body would boil!
6. The gloves included in the space suit have silicon rubber fingertips which allow the astronaut some sense of touch.
7. The full cost of a spacesuit is about $11 million although 70% of this is for the backpack and the control module.
8. Ever wondered how the pull of gravity is calculated between heavenly bodies? It's simple. Just multiply their masses together, and then divide the total by the square of the distance between them.
9. Glowing nebulae are named so because they give off a dim, red light, as the hydrogen gas in them is heated by radiation from the nearby stars.
10. The Drake Equation was proposed by astronomer Frank Drake to work out how many civilizations there could be in our galaxy - and the figure is in millions.
11. SETI is the Search for ExtraTerrestrial Intelligence - the program that analyzes radio signals from space for signs of intelligent life.
12. The Milky Way galaxy we live in: is one among the BILLIONS in space.
13. The Milky Way galaxy is whirling rapidly, spinning our sun and all its other stars at around 100 million km per hour.
14. The Sun travels around the galaxy once every 200 million years - a journey of 100,000 light years.
15. There may be a huge black hole in the very middle of the most of the galaxies.
16. The Universe is probably about 15 billion years old, but the estimations vary.
17. One problem with working out the age of the Universe is that there are stars in our galaxy which are thought to be 14 to 18 billion years old - older than the estimated age of the Universe. So, either the stars must be younger, or the Universe older.
18. The very furthest galaxies are spreading away from us at more than 90% of the speed of light.
19. The Universe was once thought to be everything that could ever exist, but recent theories about inflation (e.g. Big Bang) suggest our universe may be just one of countless bubbles of space time.
20. The Universe may have neither a centre nor an edge, because according to Einstein's theory of relativity, gravity bends all of space time around into an endless curve.
21. If you fell into a black hole, you would stretch like spaghetti.
22. Matter spiraling into a black hole is torn apart and glows so brightly that it creates the brightest objects in the Universe - quasars.
23. The swirling gases around a black hole turn it into an electrical generator, making it spout jets of electricity billions of kilometers out into space.
24. The opposite of black holes are estimated to be white holes which spray out matter and light like fountains.
25. A day in Mercury lasts approximately as long as 59 days on earth.
26. Twice during Mercury's orbit, it gets so close to the Sun and speeds so much that the Sun seems to go backwards in the sky.
27. Nicolaus Copernicus was the astronomer who first suggested that the Sun was the centre, and that the Earth went round the sun.
28. The ideas of Copernicus came not from looking at the night sky, but from studying ancient astronomy.
29. As the earth turns, the stars come back to the same place in the night sky every 23 hours, 56 minutes and 4.09 seconds. This is a sidereal day (star day).
30. When Neil Armstrong stepped on the Moon for the first time, he said these famous words: "That's one small step for a man; one giant leap for mankind."
31. From the moon, astronauts brought back 380 kg of Moon rock.
32. During the moon landing, a mirror was left on the Moon's surface to reflect a laser beam which measured the Moon's distance from the Earth with amazing accuracy.
33. The stars in each constellation are named after a Greek alphabet.
34. The brightest star in each constellation is called the Alpha Star, the next brightest Beta, and so on.
35. The distance to the planets is measured by bouncing radar signals off them and timing how long the signals take to get there and back.
36. Spacecrafts have double hulls (outer coverings) which protect them against other space objects that crash into them.
37. Manned Spacecrafts have life support systems that provide oxygen to breathe, usually mixed with nitrogen (as in ordinary air). Charcoal filters out smells/
38. Spacecrafts toilets have to get rid of waste in low gravity conditions, Astronauts have to sit on a device which sucks away the waste. Solid waste is dried and dumped in space, but the water is saved.
39. A comet's tail is made as it nears the Sun and begins to melt. A vast plume of gas millions of kilometers across is blown out behind by the solar wind. The tail is what you see, shining as the sunlight catches it.
40. The Shoemaker-Levy 9 comet smashed into Jupiter in July 1994, with the biggest crash ever witnessed.
41. Giant stars have burned all their hydrogen, and so burn helium, fusing helium atoms to make carbon.
42. The constellation of Cygnus, the Swan, contains the very biggest star in the known universe - a hyper giant which is almost a million times as big as the sun.
43. Planet Uranus was discovered by William Herschel, who wanted to name the planet George, after King George III, but Uranus was eventually chosen.
44. The first rockets were made 1,000 years ago in China.
45. Robert Goddard launched the very first liquid-fuel rocket in 1926.
46. Over 100 artificial satellites are now launched into space every year, a few of which are space telescopes.
47. The lower a satellite's orbit, the faster it must fly to avoid falling back to the Earth. Most satellites fly in low orbits, 300 km from the earth.
48. Hipparchus was the first astronomer to try to work out how far away the Sun is.
49. The red color of Mars is due to oxidized (rusted) iron in its soil.
50. Mars's volcano Olympus Mons is the biggest in the solar system. It covers the same area as Ireland and is three times higher than our Mount Everest.
51. Planets have magnetic field around them because of the liquid iron in their cores. As the planets rotate, so the iron swirls, generating electric currents that create the magnetic field.
52. Earth's atmosphere is the only atmosphere discovered till date that human can breathe in.
53. Earth's atmosphere was formed from gases pouring out from volcanoes.
54. Jupiter has no surface for a spacecraft to land on because it is made mostly from helium gas and hydrogen. The massive pull of Jupiter's gravity squeezes the hydrogen so hard that it is liquid.
55. Jupiter spins right round in less than 10 hours which means that the planet's surface is moving at nearly 50,000 km/hr.
56. The first successful planetary space probe was the USA's Mariner 2, which flew past Venus in 1962.
57. Voyager 2 has flown over 6 billion km and is heading out of the solar system after passing close to Neptune in 1989.
58. To save fuel on journeys to distant planets, space probes may use a nearby planet's gravity to catapult them on their way. This is called slingshot.
59. Hubble's law showed that Universe is getting bigger - and so must have started very small. This led to the idea of Big Bang.
60. It's believed that it was the impact of a big meteorite may have chilled the earth and wiped out all the dinosaurs.
61. The first astronomers thought the regular pulses from far space might be signals from aliens, and pulsars were jokingly called LGMs (short for Little Green Men).
62. Pulsars probably result from a supernova explosion - that is why most are found in the flat disc of the Milky Way, where supernovae occur.
63. Three moons have yet been found to have their own moons: Saturn's moon Titan, Jupiter's Lo, and Neptune's Triton.
64. The largest moon in the Solar System is the Jupiter's moon Ganymede.
65. Saturn is not solid, but is made almost entirely of gas - mostly liquid hydrogen and helium. Only in the planet's very small core is there any rock.
66. Winds ten times stronger than a hurricane on Earth swirl around Saturn's equator reaching up to 1100 km/h - and they never let up: even for a moment.
67. The first space station was the Soviet Salyut 1 launched in April 1971; its low orbit meant it stayed up only five months.
68. In April 2001, Dennis Tito became the first space tourist, ferried up to the ISS by the Russian Soyuz space shuttle.
69. Einstein's theory of general relativity shows that gravity not only pulls on matter, but also space and even 'Time' itself.
70. Since the star Deneb is 1800 light years away, we see it as it was when the emperor Septimus Severius was ruling the Rome (AD 200).
71. With powerful telescopes, astronomers can see galaxies 2 billion light years away. This means we see them as they were when the only life forms in Earth were bacteria.
72. The slowest rotating planet is Venus, which takes 243.01 days to turn around.
73. The fastest spinning objects in the Universe are neutron stars - these can rotate 500 times in just 1 second.
74. In summer in Uranus, the sun does not set for 20 years. In winter, darkness lasts for 20 years. In autumn, the sun rises and sets every 9 hours.
75. Uranus's moon Miranda is the weirdest moon of all. It seems to have been blasted apart, and then put together again.
76. Solar flares reach temperatures of 10 million °C and have the energy of a million atom bombs.
77. True binary stars are two stars held together by one another's gravity, which spend their lives whirling around together like a pair of dancers.
78. Halley predicted that a comet he had discovered would return in 1758, 16 years after his death, and it really did. It was the first time a comet's arrival had been predicted, and the comet was named after him as Halley's Comet.
79. Ceres is the biggest asteroid in the Solar System - 940 km across, and 0.0002% the size of the earth.
80. The sun is about 5 billion years old and half a way through its life - as a medium sized star it will probably live for around 10 billion years.
81. Neptune's mood Triton is the coldest place in the Solar System, with surface temperatures of -236°C.
82. Voyager 2 will beam back data until 2020 as it travels beyond the edges of the Solar System.
83. The Pioneer 10 and 11 probes carry metal plaques with messages for aliens telling them about us.
84. Einstein's theory of Special Relativity (1905) shows that all measurements are relative, including time and speed. In other words, time and speed depends upon where you measure them.
85. When things are falling, their acceleration cancels out gravity, which is why astronauts in orbits are weightless.
86. The first space telescope was the Copernicus, sent out in 1972.
87. Astronauts learn Scuba diving which helps them to deal with space walks.
88. Weightlessness makes astronauts grow several centimeters during a long mission.
89. The first living creature in space was the dog Laika on - board Sputnik 2 in 1957. Sadly, she died when the spacecraft's oxygen supply ran out.
90. The first manned space flight was made in April 1961 by the Soviet Cosmonaut, Yuri Gagarin in Vostok 1.
91. The heart of a star reaches 16 million °C. A grain of sand this hot would kill someone 150 km away.
92. Stars twinkle because we see them through the wafting of the atmosphere.
93. The sun weighs 2,000 trillion trillion tones - about 300,000 times as much as the Earth - even though it is made almost entirely of hydrogen and helium, the lightest gases in the Universe.
94. The sun gets hot because it is so big that the pressure in its core is so tremendous - enough to force the nuclei of hydrogen atoms to fuse to make helium atoms. This nuclear reaction is like a gigantic atom bomb and it releases huge amounts of heat.
95. The nuclear fusion reactions in the Sun's core send out billions of light photons every minute but they take 10 million years to reach its surface.
96. The Hiroshima bombs released 84 trillion joules of energy. A supernova releases 125,000 trillion trillion times as such.
97. The most distant galaxies (quasars) have red shifts so big that they must be moving away from us at speeds approaching the speed of light.
98. When light waves from distant galaxies are stretched out his way, they look redder. This is called red shift.
99. The moon's gravity is 17% of the Earth's so astronauts in space suits can jump 4 m high on the moon.
100. The moon is the only other world that humans have set foot on. Because the moon has no atmosphere or wind, the footprints planted in its dusty surface in 1969 by the Apollo astronauts are still there today, perfectly preserved.101. On the moon's surface are large dark patches called seas - because this is what people once believed they were. They are, in fact, lava flows from ancient volcanoes.
102. Quasars are the most distant known objects in the Universe. Even the nearest is billions of light years away.
103. The brightest quasar is 3C 273, 2 billion light years away.
104. The brightest stars in the night sky are not actually stars, but the planets Jupiter, Venus, Mars and Mercury.
105. Jupiter's moon Europa may have oceans of water beneath its dry surface and it is a major target in the search for life in the Solar System.
106. There may be 20 trillion galaxies in the Universe.
107. Galaxies are often found in a group or clusters. One cluster may have 30 or so galaxies in it.
108. In the 1970s the US Vikings 1 and 2 and the Soviet Mars 3 and 5 probes all reached the surface of Mars.
109. The Solar System has nine planets including Pluto, but Pluto may be an escaped moon or an asteroid not a planet.
110. The Milky Way belongs to a cluster of 30 galaxies called the Local Group, which is 7 million light years across.
111. The Virgo Cluster is 50 million light years away and is made up of 1000 galaxies.
112. For a satellite or a spacecraft to stay in orbit 200 km above the earth, it has to fly over 8 km/sec.
113. When a spacecraft reaches 140% of the orbital velocity i.e. 11.2 km/sec, it is going fast enough to break free of the Earth's gravity. This is called escape velocity.
114. Saturn's rings are sets of thin rings of ice, dust and tiny rocks, which orbit the planet around its equator.
115. A tablespoon of neutron star would weigh about ten billion tones.
116. The earth actually takes 365.24219 days to orbit the Sun, which is called one Solar Year. To compensate for the missing 0.242 days, the western calendar adds an extra day in February every fourth (leap) year, but misses out three leap years every four centuries.
117. X-Rays cannot reach the earth's atmosphere, so astronomers can only detect them using space telescopes such as ROSAT.
118. The Sun has sunspots, the dark spots on the Sun's photosphere (surface), 2000°C cooler than the rest of the surface.
119. After the big bang, there was antimatter, the mirror image of matter. Antimatter and matter destroyed each other when they met, thus they annihilated. Matter just won, but the Universe was left almost empty.
120. The afterglow of the Big Bang can still be detected as microwave background radiation coming from all over space.
121. Dishes in the space telescopes have to be made accurate two billionths of a millimeter.
122. You can see another galaxy with the naked eye: the Andromeda Galaxy, 2.2 million light years away.
123. Dried up riverbeds show that Mars probably once had water in its surface. There is sometimes ice at the poles and maybe water underground.
124. For a satellite to fly off into the space, its momentum should be greater than the pull of gravity of the earth.
125. The future of the Universe may depend on how much dark matter there is. If there is too much, its gravity will eventually stop the Universe's expansion - and make it shrink again.