208 FAQs about Stars in General (The Astronomy Cafe)

Palomar Digitized Sky Survey online

Photographic Guide to the Constellations

Stellar Evolution Simulator

Stellar Evolution Primer

Star Charts , Mount Wilson Observatory Star Charts

General Star Information

Mythology

  1. What do stars look like up close?
  2. What is a red giant star?
  3. What exactly happens to a star about to go supernova?
  4. If a reflection nebula is yellow, what kind of star is illuminating it?
  5. Why do planetary nebulae have hourglass shapes?
  6. What happens to the dust in a forming solar system?
  7. How do astronomers use a spectrum to find out what gases are in a star?
  8. Why do stars like our Sun only produce elements below iron?
  9. How do you convert from Gleise number to SAO number?
  10. Why don't the stars inside a globular cluster collide?
  11. How many different kinds of supernova are there?
  12. Are stellar distances known for certain or is it just theoretical?
  13. Can you see both the northern and southern constellations from the equator?
  14. Were the stars in the Great Bear in 750 BC the same ones we see now?
  15. Can X-rays be used to study the isotopes produced by supernova?
  16. Are globular clusters stable like galaxies are?
  17. How common are strings of stars, and why do they occur?
  18. Where can I get a list of double stars and some facts about them?
  19. How big is the largest star known compared to the Sun?
  20. What is the range in masses for stars?
  21. How can the maximum masses of white dwarfs and neutron stars be the same?
  22. How do astronomers determine the size and distances of stars?
  23. Why isn't Ophiuchus a zodiacal constellation?
  24. How much do the shapes of constellations change over thousands of years?
  25. If neutron stars are made of neutrons, how can they have magnetic fields which require charged matter?
  26. Where can I get the daily light curves of variable stars on the WWW?
  27. How do you compute the X and Y coordinates of a star to show its distance?
  28. Where can I get data on stars within 250 light years of the Earth?
  29. Where can I get information about the constellations, specifically Ursa major?
  30. What is a quark star?
  31. Relative to the size of our solar system, how close together are stars in globular clusters?
  32. How do you measure the age of stars and the universe?
  33. Where can I get a Hertzsprung-Russel diagram?
  34. Can we see individual stars that are outside our galaxy?
  35. Can astronomers predict when a star will become a nova or a supernova?
  36. What do you know about the constellation 'The Peacock"?
  37. Who invented the stellar classification system 'OBAFGKM'?
  38. How many constellations are there?
  39. What causes the "glow around stars"?
  40. What is the Main Sequence?
  41. Where can I find a detailed HR diagram on the Internet?
  42. Where can I get public-domain star charts for resale?
  43. How old are the oldest stars?
  44. How many constellations are there?
  45. How many stars are born each year?
  46. How many stars are there?
  47. How do some stars make dust?
  48. What is a starquake?
  49. How does dust and gas get into the sky to make stars?
  50. How heavy can stars get?
  51. Someone recently showed me a 'pillar of fire' photograph showing stars being born. What was this all about?
  52. What is the definition of a variable star?
  53. Do stars ever gain mass after they are formed?
  54. By what process do supernovae become Type I or Type II?
  55. Has the Hubble Space Telescope looked at any of the nearby stars?
  56. Why does the bright star Sirius sparkle and not planets of the same brightness?
  57. Is there a minimum and a maximum size to stars and black holes?
  58. What is the name of the bright star cluster below the Belt of Orion?
  59. Since we see stars the way they were thousands of years ago, could some of them already be gone?
  60. How long does it take for stars to form?
  61. What makes different stars age so differently?
  62. Can you hear stars?
  63. How hot do stars get?
  64. Do stars move around the Sun?
  65. How often do stars explode in space and become shooting stars?
  66. How old do stars get?
  67. How many magnitudes of extinction will a star 10 degrees above the horizon suffer?
  68. Would you see brighter stars in the sky from inside an open cluster or a globular cluster?
  69. Are there more grains of sand on the beach than stars in the universe?
  70. Why do stars evolve?
  71. Is there a constellation called "Poop"?
  72. If globular clusters are so old, why hasn't gravity collapsed them?
  73. If dead stars are rich in carbon, could their be life on them?
  74. Do stars move?
  75. Do protostars evolve into blue stars or yellow stars more often?
  76. How did people estimate the distances to stars using a candle and a pin hole?
  77. Where can I find a star map precessed to 10,500 years ago?
  78. Are there Celtic names for the constellations?
  79. What is the critical mass for producing neutron stars and black holes?
  80. How much hydrogen does a star need to shine, and does it fade as it gets older?
  81. Where can I find out which stars are 'up' this month?
  82. What is the physical reason why we can't see stars in the daytime?
  83. Where can I get images of stars on the internet?
  84. What constellation was overhead from Peru, Illinois on June 26, 1975 at 7:30 PM?
  85. Where can I get an authoritative list of stellar distances?
  86. How can globular clusters be stable when they do not rotate?
  87. How did the constellation Perseus get its name?
  88. What are the five largest constellations?
  89. How can a white dwarf have the same mass as the Sun and not 'burn'?
  90. Are the spectra of all the stars in the Milky Way different?
  91. When we see stars, have they already burned up?
  92. Is it true we can only see about 3000 stars at any one time in the sky?
  93. Are there models for stable collapsed stars where the core is made of a quark-gluon plasma?
  94. Do any stars or constellations have to do with sisters?
  95. What is a 'mature' star?
  96. Is it common for astronomers to discover new stars?
  97. Why is it so hard to find the spectral types of the bright stars?
  98. Are there non-western names for the southern constellations?
  99. Why is there so much Greek mythology in constellation lore?
  100. What happens at the Chandrasekhar Limit that lets stars collapse to neutron stars without violating the Pauli Exclusion Principle?
  101. What is stellar aberration?
  102. How were the distances to Cepheids determined as part of the astronomical distance ladder?
  103. What fraction of naked eye stars are in the three categories, bright, less bright, and faint?
  104. How is a star's magnitude related to other things we know about?
  105. How are new stars discovered or detected?
  106. How long does it take for a star to burn out?
  107. Where can I get a catalog of the CCD photometry of open star clusters?
  108. Doesn't the forcing of electrons into protons inside neutron stars violate Pauli's Exclusion Principle?
  109. How does Chandrasekhar's limit work in the formation of neutron stars?
  110. What is the magnitude of the faintest star you can see from a city with the naked eye?
  111. How do you calculate the proper motion and precession of stars?
  112. How do you compute the angular distance between two stars from their coordinates?
  113. Where can I get information about stellar populations on the WWW?
  114. Will a collapsing star always be seen as approaching its black hole or neutron star state, but never getting there?
  115. What would happen to a planet orbiting a star that has supernovaed?
  116. What time of the year is Gemini visible?
  117. What is a boson star?
  118. How are the distances to nebulae determined?
  119. If all stars in a cluster have the same age, how then can clusters be used to study stellar evolution?
  120. Can the B-V colors of stars be used to estimate their temperatures?
  121. What is a black dwarf star?
  122. Under what circumstances could a binary with a period over one year be observed as a spectroscopic binary?
  123. If stars come in all colors, why do they all appear white to the eye?
  124. What is your opinion about the work by Bauval and Gilbert on the 'Orion Mystery' and the pyramids of Egypt?
  125. Why does the 'iron crisis' occur in pre-supernova stars?
  126. Does the Big Dipper rotate around the North Star, and how long does it take?
  127. What would happen to planets orbiting two stars about to merge?
  128. How would a star loose enough mass to unbind the orbits of its planets?
  129. Why can't stars be seen in the daytime?
  130. Where can I get information about the origin of the names of the bright stars?
  131. How do you use your hands and fingers to identify constellations from a star chart?
  132. What causes the horizontal branch in globular clusters?
  133. What is the relationship between a star's color and its temperature?
  134. Can you name two stars about 550 light years apart in opposite directions, with one towards the Galactic Center?
  135. Do all O-type stars become supernovae?
  136. What happens when M-dwarf stars die?
  137. Could you give a table of the number of stars in each magnitude interval to +8 in apparent magnitude?
  138. Are Cepheid instabilities in stars associated with both giants and protostars?
  139. How do astronomers know how hot stars are when they are so far away?
  140. Does the Hyades cluster in Taurus have a Messier number, and if not, why?
  141. If a star burns oxygen before it becomes a supernova, why can't we look for stars in this phase as precursors to a supernova?
  142. Do star colors tell you anything about the gases they contain?
  143. How do you define stellar evolution in three sentences or less?
  144. If the Cepheid star method gives you luminosity, how do you then determine distance from this knowledge?
  145. Where do the magnetic fields in neutron stars come from?
  146. What happens when two stars collide?
  147. Could you define radial, transverse and space velocity, and proper motion?
  148. What are the three most important types of variable stars?
  149. How are the names of stars in a constellation assigned?
  150. Exactly how do astronomers determine distances to stars using parallax?
  151. Do we know who named the bright stars in the sky?
  152. Where can I get information about the nature of stars?
  153. Can a star have rings around it like some planets do?
  154. Are binary stars more common than single stars?
  155. Why is it difficult to estimate the mass of a star?
  156. What is the size ratio of Antares to Proxima Centauri?
  157. How faint would the faintest star in the galaxy be under ideal circumstances?
  158. How can you tell a star has starspots when you can't even see the star's surface?
  159. Are sunspots seen on other stars always dark?
  160. What is a neutrino star?
  161. Where can I get star charts?
  162. Which star has the most colors?
  163. Why do some stars have colors?
  164. Why are stars so important to astronomers?
  165. Why did people name the constellations long ago, and can we rename them today?
  166. How long is the average life of a star?
  167. Who named the southern constellations?
  168. When a star burns out, what happens to its planets?
  169. Is a brown dwarf a star or a planet?
  170. What is the 'moving cluster method' for determining stellar distances?
  171. Are there any reference books that describe in detail the F5-K5 stars within 25 parsecs of the Sun?
  172. How do you derive stellar luminosities from distance and apparent magnitude?
  173. Where can I get information about stellar spectral types, distances etc?
  174. What is the difference between a globular cluster and an open cluster?
  175. If a star becomes a supernova, what would happen to life on planets in nearby solar systems?
  176. What is the largest distance between stars in a binary star system?
  177. Do sunspots occur on all stars, even white dwarfs and neutron stars?
  178. Is the color of a star determined by the elements it burns?
  179. What is the last element that a star burns?
  180. What causes pulsating variable stars to pulsate?
  181. What is the best guess for the number of stars in the universe?
  182. Can you see stars from the bottom of a well?
  183. How do you use photographs to measure the brightness of stars?
  184. Do the stars really move at night?
  185. Are there any classification systems for planets and stars?
  186. What is the basis for the stellar magnitude system; is one star (Sirius/Polaris) taken as 1.0 and the rest compared to it?
  187. Can I have a star named after my wife on our anniversary?
  188. Why do some stars change in their brightness and others not?"
  189. How do astronomers figure out the ages of stars?
  190. How many stars can you see from the Earth?
  191. Why aren't there any green stars?
  192. How many stars are there like the Sun?
  193. Do stars really twinkle because light is refracted off air molecules?
  194. How is a star's size and temperature related to its brightness?
  195. How many stars are there within 10 light years of the Sun?
  196. What kind of terrestrial atmosphere would make stars look green?
  197. Is a supernova the same thing as a nova, but just brighter?
  198. Have astronomers observed stars that have gone out?
  199. If you took a telescope to the North Pole and looked straight up, would you see anything?
  200. What would happen if two stars collided?
  201. How often do stars collide in the Milky Way?
  202. How fast do stars move through space?
  203. If a star were to loose mass, what would happen to the orbits of planets?
  204. Do stars ever loose mass after they are formed?
  205. How hot can a star get?
  206. Would a planet orbit in a figure-8 path in a binary star system?
  207. How do white dwarfs support themselves against gravitational collapse?
  208. How did Cecilia Payne-Gaposchkin use hydrogen and helium lines to determine distances to stars?

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