1. There is an asteroid on a collision course with the Earth.

2. The largest asteroid is Ceres, which is about a quarter the size of the moon.

3. A spacecraft returning from an asteroid is not limited to carrying water.

4. The importance of Spacewatch and other asteroid search programs becomes more evident as we learn more about the impact hazard.

5. Hundreds of asteroid spectra have been compared with laboratory reflection spectra of meteorites and pure mineral samples.

6. Were this asteroid to hit an ocean, it would create massive tidal waves that would roar far inland on all continents.

7. Unfortunately, determining the physical properties of an asteroid be-fore its impact is quite challenging.

8. The spectral classes established by asteroid observers are based on the colors and total reflectivity of their targets.

9. But some, including Eros, wander out of the asteroid belt and into the inner solar system during each orbit.

10. Therefore a carbonaceous asteroid, although unlikely, can not be ruled out as an explanation of the Tunguska event.

11. The asteroid flew within 106,000 miles of Earth, which astronomers considered a near miss.

12. The pictures were taken during the spacecraft's 25-minute flyby of the asteroid.

13. Ninety-nine out of a hundred wildcatters went broke or crazy or both and abandoned their last asteroid with the equipment in situ.

14. Finally the day arrived when they were ready to begin loading the asteroid for the trip.

15. Much water has been lost for ever from Mars, blasted into space by comet and asteroid impacts.

16. Astronomers had accidentally caught a comet in the act of turning into an asteroid.

17. For operations in the region of space from Earth out to the asteroid belt, we need only extract water.

18. Clearly, the iron-nickel metal on the surface of the Moon is contributed by asteroid impacts.

19. The easiest explanation of crater duplicity is that the impacting body was an asteroid with a close satellite.

20. We followed the drawings of the little prince with his simple round face and spiky hair, standing on his asteroid world.

21. New evidence supports the theory that the dinosaurs were wiped out by an asteroid.

22. Similarly, granting a carbonaceous object the strength of a stony asteroid would allow it to penetrate to comparable altitudes.

23. Their utility in servicing traffic from Earth to the asteroid belt is, however, dubious.

24. Closed in on herself, Jezrael felt only apathy during the flight to Spiderglass guard-school, hidden out in the asteroid belt.

25. Such ease of access means that very large masses of asteroid materials can be returned to the vicinity of Earth.

26. The narrow confines of the inner solar system seem claustrophobic compared to the asteroid belt.

26. try its best to gather and create good sentences.

27. Their aim was to capture high-resolution images of the asteroid on the way down.

28. The large majority of all Amors reach out into the heart of the asteroid belt near aphelion.

29. Noise proves nothing, Often a hen who has laid an egg cackles as if she had laid an asteroid. Mark Twain 

30. We do it now on a small scale to bring the rocks into Earth orbit from the asteroid belt.

31. Most meteorites are thought to come from the asteroid belt between Mars and Jupiter.

32. All but one of these orbit in the asteroid belt, safely beyond the orbit of Mars.

33. Through the high-powered telescope, they could see that the asteroid was very irregular, and turning slowly end over end.

34. In 1976 a small asteroid, 2062 Aten, was discovered in an orbit that actually circles the Sun faster than Earth.

35. The number of trips that can be expected for a spacecraft that transports water back from an asteroid is difficult to estimate.

36. Thus the four terrestrial planets are all affected in important but very different ways by comet and asteroid impacts.

37. Three small NEAs have spectra very similar to those of basaltic achondrites and of the asteroid Vesta.

38. All this data combined will allow scientists to determine Eros's density, and any density variations deep inside the asteroid.

39. The solid residue left after baking the volatiles out of carbonaceous asteroid materials is of considerable interest in its own right.

40. Against the darkened portion of the asteroid there was a sudden, dazzling explosion of light.

41. For example, Vesta, the fourth-largest asteroid, reflects light in a unique way: some 50 meteorites match it closely.

42. The measured brightness variations over the rotation period are called the light curve of the asteroid.

43. The effects of comet and asteroid impacts are potentially damaging to life in general, and to human civilization in particular.

44. The asteroid belt is broadly zoned into bands of different classes of asteroids.

45. Scientists speculate that a giant asteroid hit Earth millions of years ago.

46. An elaborate system of spectral classes has been established by a persistent cadre of asteroid observers.

47. The first and largest asteroid discovered, Ceres, was found on the night of January 1(), 1801.

48. The Father General and the asteroid and the plane and all these people working on this crazy idea.

49. It was the bicentenary of the discovery of the first asteroid.

50. The continuous bombardment of asteroid surfaces by small impactors generates a constantly replenished supply of crushed rock.

51. Asteroid lies between Mars and Jupiter.

52. Gargantuan asteroid to pass near Earth this fall.

53. Could an asteroid obliterate Los Angeles?

54. This asteroid takes 238 years to orbit the sun.

55. You're not actually going into an asteroid field?

56. Large meteorites actually come from the asteroid belt.

56. Wish you can benefit from our online sentence dictionary and make progress every day!

57. These spacecraft can be launched by electromagnetic mass drivers from the Moon to the planets, their satellites, and to the asteroid belt.

58. Dodge being hit in an asteroid belt, and get ready to land as you approach a deserted moonscape.

59. It's very unlikely that an asteroid will crash into Earth but the danger exists.

60. In March, NASA’s Messenger mission is due to become the first craft ever to orbit Mercury, and the agency’s Dawn probe will orbit one of the biggest members of the asteroid belt, Vesta, in August.

61. Unbound to Earth, our species could imagine that an age of spacefaring was truly under way, the Moon and Mars within reach, maybe even an asteroid where the Little Prince awaited our visit.

62. The NEAR - Shoemaker probe touched down after studying the asteroid Eros for the past year.

63. In 2001, Galileo detected that an asteroid had struck the moon, forming the Valhalla impact basin.

64. Chlamydia trachomatis anti-bma can use fluorescent element of monoclonal antibodies dye, all in fluorescence microscopy observation to an asteroid flashing fluorescence point which is positive.

65. Parking an asteroid in a gravitationally neutral spot between the Earth and the sun, known as a Lagrange point, would provide a stationary base from which to launch missions further into space.

66. Helfand added that tracking an asteroid is just the first step.

67. An asteroid splashdown in one of Earth's oceans could trigger a destructive chemical cycle that would wipe out half of the ozone layer, according to a new study.

68. Try the Asteroid Belt sample and Fish Tank sample on the test drive site to see hardware accelerated Canvas in action.

69. The theory that has developed is that asteroids in the the Asteroid Belt between Mars and Jupiter may have produced smaller meteorites which have shot off into space and landed on Earth.

70. The asteroid was first spotted during a routine survey performed by a satellite. But it was the asteroid's earthlike orbit that really got the astronomers'attention.

71. For the first time, ground-based telescopes spotted a tiny moonlet orbiting a mere asteroid in Earth's own solar system.

72. Dactyl is the first moon of an asteroid ever discovered.

73. You cannot make the jump to light - speed in this asteroid field.

74. Like a sunburn on your skin, the reddening of an asteroid is only skin deep, with fresher material lurking just beneath the sun-drenched surface of the space rock, he added.

75. A weaker explosion—one slightly smaller than the Hiroshima blast—would create shards that would reconsolidate due to gravity, so that the asteroid would stitch itself back together in less than a day.

76. The object, dubbed P/2010 A2, orbits the sun well within the main asteroid belt, according to observations taken as part of the Lincoln Near Earth Asteroid Research sky survey.

77. This artist's animation illustrates a massive asteroid belt in orbit around a star the same age and size as our Sun.

78. Humanity needs more than one home because, with all our eggs in one basket, we are at risk of low-probability but high-consequence catastrophes like asteroid strikes, nuclear war or bioterrorism.

79. The JPL team takes orbit data from the Minor Planet Center and refines it, asteroid by asteroid.

80. Launched in 2007, Dawn is the first mission to explore Vesta and Ceres, the two largest members of the asteroid belt.

81. It most likely happened after a cataclysmic comet or an asteroid impact 65 million years ago.

82. The bad news is that forecasting asteroid impacts remains a tricky business.

83. A suitable asteroid might have its orbit modified so that it could be parked at the Earth-moon Lagrangian point 5, a gravitationally stable location in circumlunar space.

84. That matters because the asteroid is one of the oldest known objects in the solar system, having formed a mere 5 million years after the solar system started to congeal.

85. ScienceDaily (July 18, 2011) —NASA's Dawn spacecraft on July 16, 2011 became the first probe ever to enter orbit around an object in the main asteroid belt between Mars and Jupiter.

86. An asteroid seeding issue in the G 5 KW region has been addressed.

87. Between the orbits of Mars and Jupiter lies the asteroid belt, which includes the dwarf planet Ceres.

88. These asteroid - sized objects pack sunlike masses, extremely small orbits, and incredibly fast spins.

89. Then he sent Jenniskens figures detailing the address—latitude, longitude and altitude—of the asteroid every six miles en route to Earth, plus its speed and angle of approach.

90. Because at least one asteroid appears to be coated by a thin layer of ice. And just that kind of asteroidal frosting could have been the source of our water here on Earth.

91. Astronomers have long thought that the asteroid belt is being ground down through collisions, but such a smashup has never before been seen.

92. Terrestrial planets could reside inside the innermost asteroid belt as well, though there currently is no clear indication of that, Marengo said.

93. Paleontologist Dave Raup postulates that 75 percent of all extinction events were caused by asteroid impacts.

94. At first, astronomers thought it might be a so-called "main belt comet"--a rare case of a comet orbiting in the asteroid belt.

95. A nearby star, visible with the unaided eye, is ringed with two rocky asteroid belts and an outer icy halo, making it a three-ring cosmic circus.

96. Hubble has trained its new camera on the atmospheric disturbance on Jupiter believed to have been caused by a comet or asteroid impact.

97. The Geminides originate from mysterious 3200 Phaethon , which is an asteroid.

98. The asteroid is too dim to be seen with the naked eye and its gravity is too weak to affect tides or earthquake activity, said experts at the National Aeronautics and Space Administration.

99. In the past 10 years, the Alley has endured the triple asteroid strikes of an exploding Internet Bubble, the 9/11 terror attacks and the financial crisis. Thousands of firms went belly-up.

100. Epsilon Eridani is surrounded by not one but two asteroid belts, a possible sign that other, more Earth-like planets could be nearby on the inside of that belt, as Earth is in our solar system.

101. To speed up or slow down the asteroid, the space tug must keep the direction of thrust parallel to the body's orbital motion.

102. The two bodies are the most massive objects in the asteroid belt.

103. The inner asteroid belt be a virtual twin to the belt in our solar system.

104. Part of such planetesimals entered the asteroid region, drew out most of the matter there, and increased the random velocity of the asteroids that remained, so they could not combine to form a planet.

105. Astronomers have long thought that the asteroid belt is being ground down through collisions, but such a smashup has never been seen before.

106. Earlier studies have shown that the Earth does the same thing with dust released from the asteroid belt.

107. "You're moving the largest mother lode imaginable " said former astronaut Rusty Schweickart cofounder of the B612 Foundation an organization dedicated to protecting Earth from asteroid strikes.

108. The asteroid vaporized on impact, launching a cubic mile of rock into the sky.

109. Ananke, Carme, Pasiphae and Sinope may be remnants of a single asteroid that was captured by Jupiter and broken up.

110. An asteroid or comet fragment around 60 meters across is believed to have been behind the Tunguska Event, a powerful explosion that took place over Russia in 1908.

111. But he wanted to locate the impact site of the asteroid.

112. Like a frozen asteroid belt, it’s littered with chunks of ice and frozen methane and ammonia.

113. Between the orbits of Mars and Jupiter lies the asteroid belt.

114. The cosmic pile-up is the first ever witnessed in the asteroid belt, 90 million miles away in space.

115. The Pleiades won, and Maldek was shattered by spacecraft thus becoming your asteroid belt.

116. It is also the former number of Route 491, a brand of cough syrup, and forms part of the name of 666 Desdemona[http:///asteroid.html], a minor planet in the asteroid belt.

117. So Pluto should be a planet, as should Eris and the dwarf planet Ceres (the largest body in the asteroid belt between Mars and Jupiter), as well as many other objects.

118. And those numbers conspire to give asteroid fatalities a worryingly high annual average between collisions.

119. The researchers made a similar discovery in April this year when they discovered the first evidence of ice on an asteroid called 24 Themis.

120. The debris possibly came from a comet or asteroid that hit Jupiter.

121. Gostin, who first discovered rocky traces of the asteroid "ejecta" almost 30 years ago, said the asteroid impact occurred during a period of extreme cold.

122. A meteorite (pictured) from an asteroid landed in Sudan's Nubian Desert in 2008.

123. The planetlike object Ceres would have to be in a separate class, because it resides in the main asteroid belt, between the orbits of Mars and Jupiter.

124. We present a design concept for a spacecraft that can controllably alter the trajectory of an Earth-threatening asteroid by using gravity as a towline.

125. Asteroid hyalosis is a degenerative condition of the eye involving small white opacities in the vitreous humor.

126. Though the Cretaceous asteroid cleared the stage, mammals did not really get going until 10m years later, in the Eocene epoch.

127. The not-so-romantically named (101955) 1999 RQ36 -- discovered in 1999 -- measures approximately 510 meters in diameter and is classified as an Apollo asteroid.

128. Moving on through the asteroid belt we enter the realms of the gas giant planets: Jupiter, Saturn, Uranus and Neptune, all of which dwarf the Earth.

128. try its best to gather and create good sentences.

129. Plans for eventual missions to an asteroid and to Mars could be decades away. But Daytona Beach, Florida resident Rob Hansen is more optimistic.

130. Asteroid has become commonplace to the readers of interstellar travel stories in science fiction magazines.

131. Astronomers have yet to witness an asteroid impact with another planet.

132. The inner belt orbits at a distance of about 3 astronomical units from its star--or about the same position as the asteroid belt in our own solar system.

133. According to the Daily Telegraph of October 9, water ice and organic molecules that help to form the basis of life have been discovered on a second asteroid, called 65 Cybele, by astronomers.

134. Recently, scientist have also discovered comets in the main asteroid belt —these main-belt comets might be a key source of water for the inner terrestrial planets.