106 What would make scientists realize they were on a flat world? 2016-05-27T13:02:38.770

80 Can stars that are not powered by nuclear fusion exist? 2015-08-17T17:03:07.400

71 Is it physically possible for a planet to have seasons of different lengths? 2014-09-17T14:58:11.893

66 Could a disaster kill all (human) life on Earth but leave astronauts in low orbit alive long enough to return? 2014-10-15T12:29:29.090

65 How would an astronaut conclude he's on Earth, but 600 million years in the future? 2017-06-17T00:07:44.217

61 How could a planet have a sky without stars at night? 2019-01-02T21:18:36.153

58 What would it feel like on the surface of a planet while it collides with another planet? 2016-04-18T14:28:23.447

57 How would someone hide an asteroid in the void of space so only they could find it? 2016-06-23T15:47:30.223

47 What would the sky look like from the surface of a planet with rings? 2014-10-15T03:45:36.470

45 How long will it take to discover they live on a moon and not on a planet? 2018-09-20T17:42:38.933

37 Can I keep our universe, but without the speed limit (of light)? 2014-11-05T07:50:33.890

37 Can a planet survive a supernova? 2015-06-11T21:44:18.190

36 Can a planet realistically have multiple suns? 2014-10-15T19:43:05.993

36 Habitable moon of a gas giant: working out the sizes and distances 2015-01-05T20:37:15.170

34 How to create an annual celestial event for a world 2018-02-21T16:43:14.163

33 What's an astronomical event which happened about 10,000 years ago, which humans could have noticed? 2018-12-20T19:59:02.477

32 What Factors Could Cause a World to See "Northern" Lights Much Closer to the Equator? 2014-09-16T19:17:19.980

31 What software can prototype a planetary system? 2014-10-09T11:20:15.927

31 Would life on the edge of the Sagittarius Dwarf Spheroidal Galaxy see the whole Milky Way in the night sky? 2017-05-03T12:15:38.253

31 If Sweden was to magically float away, at what altitude would it be visible from the southern hemisphere? 2019-05-28T10:06:48.127

29 Creating a realistic world(s) map - Stars 2015-08-20T18:54:31.173

29 Would 'cheap' FTL make powerful telescopes obsolete? 2016-02-13T14:52:49.257

29 How could a planet have one hemisphere way warmer than the other without the planet being tidally locked? 2019-09-03T14:26:38.377

28 Can a dedicated amateur astronomer spot a rogue asteroid? 2017-08-29T08:05:05.383

28 Why didn't we detect that exoplanet before? 2017-12-04T11:48:43.073

28 In a world without stars, how would travelers navigate at night? 2020-01-01T19:19:01.280

27 Building the Death Star with today's tech 2014-11-02T04:07:40.370

27 How deep can the ocean plausibly be? 2015-11-26T12:48:09.477

27 What would the effect be on Earth if Mars disappeared? 2016-08-03T08:56:53.990

27 What could make a planet more radioactive at night? 2018-05-13T08:00:23.687

27 Is there any conceivable way to "turn off" a star? 2019-11-26T18:15:47.377

26 Could life form in outer space? 2014-10-10T09:07:37.587

26 How can a planet have a deadly eclipse-like "spotlight"? 2019-01-07T14:42:59.953

25 Making a Planet Seem Uninhabitable 2016-12-07T16:33:25.333

25 How would skeptics know that a single-engine plane could not destroy a falling meteor? 2018-07-26T16:39:07.413

24 On a planet without seasons, how would people track years? 2014-10-15T22:52:04.210

24 What do Martians use for months and weeks? 2017-12-20T01:18:42.090

23 How would solar activity change if the Sun was impacted by a planet? 2014-11-05T15:40:19.543

23 How big a black hole is needed for this story? 2015-04-17T05:39:38.423

23 Can you replace a sun with a burning moon? 2017-04-28T17:17:43.373

23 Is it possible to have a sun with visible phases or cycles? 2017-05-11T18:24:39.913

22 Is it safe to orbit HDE 226868? 2017-02-22T14:52:08.260

22 Is a "long exposure"-like night sky possible? 2017-11-07T21:13:35.040

22 Music from the Stars - How would a star-sound-machine work? 2017-12-20T13:38:46.740

22 Scientific explanation for a exceptionally bright night sky 2018-12-21T11:25:36.267

21 What technologies and sciences are needed to detect a star going supernova? 2015-01-04T11:09:52.370

20 How could a smaller planet than Earth have a higher gravity? 2014-12-07T09:23:54.577

20 Close the door on your way out - Life lit by a blue dwarf star 2015-08-23T11:01:13.957

20 Are planetary orbits absolutely necessary? 2016-08-14T16:51:36.400

20 What would the sky look like in the SHADOW of planetary rings? 2017-01-03T20:16:30.687

20 How would other planets in a solar system be affected by the disappearance of one planet? 2017-03-20T23:31:17.257

20 How could the current model of the Solar System have been recognized and accepted earlier? 2018-02-02T14:45:43.087

20 Physiological adaptation of life on a planet orbiting a red giant. 2018-03-15T03:38:59.033

19 Earth-like Moon around the Gas Giant. Eclipse length? 2017-02-13T04:44:01.993

19 What would the consequences be of a high number of solar systems being within close proximity to one another? 2019-06-10T17:52:46.117

18 How would two planets with identical but perpendicular orbits affect each other? 2014-09-22T23:10:51.270

18 What determines the length of a day on a planet? 2014-09-29T01:23:11.257

18 Could a society exist within a brown dwarf? 2015-02-10T16:36:00.653

18 How long would it take us to notice Pluto disappearing? 2016-09-21T19:56:42.877

18 How to verify correctness of a galaxy map? 2016-12-30T11:58:30.330

17 Biological Spaceships - Possible? 2015-02-07T20:53:45.867

17 Starbuilding: What is lacking in the logic behind Cosmos 2 star system generation algorithm? 2016-05-05T12:00:08.287

17 How would a torus world (donut shaped) have to rotate in order to have a stable day / night cycle in all of its regions? 2017-04-20T15:49:50.567

16 By what mechanism could a planet be locked into permanent solar eclipse? 2014-11-22T01:38:59.567

16 What would be the effects of galaxies colliding? 2015-11-17T18:06:48.167

16 How long would it take a civilization to see and understand a Dyson ring? 2018-01-17T19:04:39.050

16 To make a gas giant flammable 2018-01-23T16:59:23.683

16 What software could I use to simulate my world's sky? 2018-07-11T14:53:00.407

15 Could a moon have its own satellites visible from the planet it orbits? 2015-03-29T04:20:30.103

15 What would we see of a devastating interstellar war between alien civilizations within 1000 Ly? 2015-09-16T00:08:23.617

15 What impact is required for a visible (from Earth) ejecta plume on Earth's Moon, and would the Moon survive? 2016-12-15T20:44:49.277

15 Could the Sun be born again? 2018-06-07T13:10:14.817

14 Can a habitable planet have mini-suns (i.e. solar satellites or glowing moons)? 2016-01-30T11:24:55.267

14 Would mining huge amounts of resources on the Moon change its orbit? 2019-03-18T08:18:34.163

13 What effect would three moons have on ocean/landscape formation? 2014-10-15T19:09:23.443

13 How would life on the satellite of a Super-Jupiter be? Is it even possible for such a satellite to be habitable? 2015-02-21T18:47:55.180

13 How can a Type II civilization influence accretion rates from a debris disk to a passing star? 2015-03-19T21:54:31.633

13 How could a dust cloud form around a middle-aged star? 2015-03-28T21:59:07.670

13 You've made it to another star! Now, how do you find its planets? 2015-04-10T15:56:17.067

13 Detecting a neutron star entering the solar system 2017-02-24T12:21:56.573

13 How to blow up a star by accident? 2017-07-16T14:24:30.780

13 Can two moons orbit each other while orbiting a much larger planet? 2017-07-18T20:06:05.090

13 Would everything be miniature on a miniature Earth? 2018-07-11T08:04:23.947

13 How can a moon have an ever-changing face? 2019-01-17T17:21:34.910

13 Rogue Planet Illuminated by Galactic Centre 2019-07-27T15:19:51.573

12 Planet illuminated by blue-shifted relic radiation 2014-11-05T17:55:09.297

12 What would a pair of Death Stars do to Earth? 2014-11-23T19:21:52.613

12 How can my accidental time travelers determine the year using star/stars? 2015-02-05T14:21:36.317

12 How can I set a moon on fire? 2015-03-29T14:35:00.913

12 What did the night sky look like 63 million years ago? 2015-04-09T05:43:18.997

12 Could life exist in a circumstellar disk? 2015-08-18T15:58:10.807

12 How would the night sky appear from the inside of a star cluster? 2016-01-31T20:59:08.240

12 Could life evolve in the degenerate era of the universe? 2016-03-11T20:19:47.403

12 If I were to put a moon-mass object in Mars orbit, how long would it take to restart the dynamo effect in Mars' core? 2018-01-13T19:04:10.463

12 Can a planet's axial tilt naturally change a meaningful amount in only 100 years from its current cycle? 2018-02-16T13:40:00.703

12 How to calculate hour angle of a moon? 2018-03-03T00:25:55.503

12 How close could another solar system be without adversely affecting our own? 2019-01-04T13:26:54.553

12 Can planetary bodies have a second axis of rotation? 2019-09-17T22:58:00.147

11 Where would an asteroid have to hit earth to cause an impact winter? 2014-10-09T21:19:52.143