| If we observe a star X light years away, does that mean theres nothing inbetween here and there obstructing our view? Posted: 22 Mar 2017 02:44 AM PDT |
| Why is the wheel damage on the Curiosity rover so bad compared to Opportunity? Posted: 21 Mar 2017 04:58 PM PDT Recently in the news curiosity's wheel damage has been a subject of worry. I have yet to see a concise explanation as to why exactly the wheel damage is so bad compared to the 13 year old curiosity rover. Why is that, whats different between the two rovers or the two terrains? submitted by /u/wegener1880 [link] [comments] |
| Was the cosmic microwave background once visible light? Posted: 22 Mar 2017 04:00 AM PDT From what I understand of the CMB it was initially very high energy and high frequency and as the universe cooled and expanded the light was shifted down to microwave radiation. Does that mean that at some point in the history of the universe the night sky was lit up in a specific color of light that we would be able to see? And going further was that point in time a time when there were solid planets and the universe pretty much as we know it now? submitted by /u/ZacharyCallahan [link] [comments] |
| What is the maximum heat of any known solid? Posted: 21 Mar 2017 04:16 PM PDT My son asked me tonight if it was possible for something to be as hot as the sun and still be a solid and I couldn't give him an answer. Help! submitted by /u/FinnFerrall [link] [comments] |
| If neutrons only have a half life of 10 minutes, why don't neutron stars just disappear after this time? Posted: 22 Mar 2017 02:06 AM PDT I'm currently studying particle physics in my Physics A level and I found out yesterday that neutrons only have a mean half life of around 800 seconds. This made me wonder why neutron stars don't decay after 10 minutes because they are made purely of neutrons. I asked my Physics teacher the same question and he brushed the question off in an "I don't really know" kind of way. submitted by /u/NachoftheMach [link] [comments] |
| How do electronic devices detect battery percentage? Posted: 22 Mar 2017 04:48 AM PDT |
| Is it possible to send a powerplant worth of electricity through a small wire of superconducting material? Posted: 22 Mar 2017 03:54 AM PDT Hey AFAIK the point of these big power lines for the high voltage is to minimize the resistance and through that the enegergy loss, but if we invent a high temperature superconductor, would we be able to replace the power grid of the world with cables of lets say the size of a normal household power cable? submitted by /u/KippieDaoud [link] [comments] |
| Ask Anything Wednesday - Biology, Chemistry, Neuroscience, Medicine, Psychology Posted: 22 Mar 2017 08:04 AM PDT Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Biology, Chemistry, Neuroscience, Medicine, Psychology Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...". Asking Questions: Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions. The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit /r/AskScienceDiscussion , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists. Answering Questions: Please only answer a posted question if you are an expert in the field. The full guidelines for posting responses in AskScience can be found here. In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for /r/AskScience. If you would like to become a member of the AskScience panel, please refer to the information provided here. Past AskAnythingWednesday posts can be found here. Ask away! submitted by /u/AutoModerator [link] [comments] |
| How did Edward Witten unify the 5 different string theories into one M-theory? Posted: 21 Mar 2017 06:08 PM PDT Like most people I don't know much about string theory so I was wondering if someone could explain it as I'd really like to understand (at least in layman's term). Thank you. submitted by /u/deeaxident [link] [comments] |
| Are electrons, protons and neutrons actually spherical? Posted: 21 Mar 2017 07:55 AM PDT Do we have any proof they are spherical or do we just assume such due to their motion or reactions or some other observation? submitted by /u/ethanbird1 [link] [comments] |
| What is the difference between the Particle Horizon (which, according to Wikipedia, is the "boundary between the Observable and Unobservable Universe) and the Cosmological Event Horizon (16 billion light years away)? Posted: 21 Mar 2017 02:06 PM PDT On Wikipedia, for the Cosmological Event Horizon, it says that: "This fact can be used to define a type of cosmic event horizon whose distance from the Earth changes over time. For example, the current distance to this horizon is about 16 billion light years, meaning that a signal from an event happening at present can eventually reach the Earth in the future if the event is less than 16 billion light years away, but the signal will never reach the Earth if the event is more than 16 billion light years away." https://en.wikipedia.org/wiki/Observable_universe So does this mean that any object past this limit of 16 billion light years away currently will be emitting light that is impossible for observers on Earth to ever see? Also, according to Wikipedia, the Particle Horizon: "represents the boundary between the observable and the unobservable regions of the universe." https://en.wikipedia.org/wiki/Particle_horizon But here's what I am confused about is this: "the particle horizon represents the largest comoving distance from which light could have reached the observer by a specific time, while the event horizon is the largest comoving distance from which light emitted now can ever reach the observer in the future." https://en.wikipedia.org/wiki/List_of_cosmological_horizons This sentence just makes no sense to me. Could someone please explain it? It's really making my brain hurt cuz they both just sound the same to me. submitted by /u/123td1234 [link] [comments] |
| Is it possible to magnetically levitate an object with total freedom of rotation? Posted: 22 Mar 2017 01:44 AM PDT |
| How can we be sure that planets light years away will still be there when we get there? Posted: 21 Mar 2017 03:29 PM PDT |
| Can earphones/speakers be "overloaded" if I played, say, 1,000 songs through them at the same time? Is there a max? How can speakers/earphones handle several unique songs seemingly all at once? Posted: 21 Mar 2017 02:05 PM PDT |
| How can you justify multiplying a wavefunction with a spin vector? Posted: 21 Mar 2017 01:40 PM PDT Since the wavefunction and spin live in different Hilbert spaces, what allows you to multiply them with each other? Also, the total symmetry of the function is the same, as if you would multiply 2 functions of the same space with each other, how can this be? submitted by /u/digitalmus [link] [comments] |
| Can plants get cancer? Posted: 21 Mar 2017 11:46 AM PDT |
| If we were to reduce a particle's mass to zero continuously, would its worldline smoothly go from a timelike to a null geodesic? Posted: 21 Mar 2017 12:17 PM PDT In relativity, the trajectories of particles follow worldlines. Massless particles (like photons) follow null worldlines, whose norm is zero, but massive particles' worldlines have a norm of 1. Is the zero-norm null geodesic just the low-mass limit of a massive particle's trajectory? submitted by /u/eebootwo [link] [comments] |
| Will the Cosmic Microwave Background Radiation turn to Radiowaves as the universe further expands? Posted: 21 Mar 2017 01:05 PM PDT I always wondered why the light of the CMBR, that has been increasing in wavelength since it's formation, hasn't moved even farther to the low energy part of the EM spectrum in the last 14 billion years. As the universe is still expanding this eventually has to happen, right? How long would it take until we classified the radiation as radiowaves? submitted by /u/powerpaddy [link] [comments] |
| What determines if a white dwarf goes nova or supernova? Posted: 21 Mar 2017 10:09 AM PDT A white dwarf accumulating mass from a companion can either blow off the mass in a nova at a regular interval or when it reaches 1.44 solar masses (Chandrasekhar limit) it will turn into a type Ia supernova. Both of these processes start the same way, so what factor determines if the mass being siphoned off will turn into a nova or create a supernova? Also, if a white dwarf is periodically going nova, will it hit a point where it will siphon off enough matter to create a supernova, or are the conditions never right for that? submitted by /u/vizard0 [link] [comments] |
| When are Bremsstrahlung photons created? Posted: 21 Mar 2017 09:06 PM PDT Currently studying 2nd year physics at university. When exactly are bremsstrahlung photons created when an electron curves around a nucleus? I understand how they are produced, but the photon has to be ejected at a certain time right? When exactly in the interaction are the created? submitted by /u/Palanator [link] [comments] |
| How has the core of the earth been able to retain its heat for so long? Posted: 21 Mar 2017 11:09 AM PDT |
| How far can radio signals sent into space travel while still remaining "readable?" Posted: 21 Mar 2017 09:30 AM PDT If we sent out a radio broadcast into space and could hypothetically travel faster than light to get in front of it, is there a limit to the distance we could go and still be able to read the signal? Do radio waves degrade over time or would it be theoretically possible to travel 80 light years away and watch an original airing of "I Love Lucy?" submitted by /u/LaserRed [link] [comments] |
