Astronomy and Cosmology

Hi all some questions for the asteroid on April 30. According to NASA it will be 16 times further than the earth to the moon. 1- How can they know this for sure? 2- How do we know they are being honest with the distances? 3- are they the Only ones able to make these calculations? 4- Several news sites had articles that it would hit and this was secret info from NASA? 5- another site claimed that the Coronavirus was brought up to keep people isolated because of this asteroid to avoid mass panic, so how do we know what’s real vs fiction on this? These things make it hard to determine what is right dosent it? thank you

Do they pull or push earth in/toward the sun?

I heard about this from Neil DeGrasse Tyson on the Stephen Colbert show last night. Does anyone know what caused this? The "bang" or gamma ray burst was so giant that it carved a hole 1.5 million light years wide through a galaxy cluster. The article says nothing about the mass of the supermassive black hole. It must be tens of billions of solar masses, maybe the result of the merger of 2 ultra massive black holes during a galaxy collision? Any ideas? Is was a quasar for hundreds of millions of years, to produce that cavity. Why do they call that a "bang"? It was a giant quasar. “But it happened very slowly – like an explosion in slow motion that took pla…

I just saw a documentary on Netflix called "Bob Lazar, Area 51, and Flying Saucers." Bob is an interesting character who seems very credible. The narration by Mickey Rourke is a bit surreal, but the graphics are interesting. I watched the movie a second time, with captioning on so I could read it all, because I wanted to investigate this movie more carefully. Has anyone seen this Netflix, or are you familiar with Bob Lazar? He claims there are up to 9 alien saucers at S4, and a couple of them operate. Bob was reverse engineering the gravity propulsion, that uses an antimatter reactor that works by a stable form of element 115. He was raided twice by the govt. …

Hi, I would like to share with you guys a couple of interesting simulations. This simulation belongs to an Earth-like planet located 4 light-years away, imaged with the European Extremely Large Telescope (ELT), expected in 2025: This other simulation belongs to an Earth-like planet located 40 light-years away, imaged with the Large Ultraviolet Optical Infrared Surveyor (LUVOIR), expected in 2035: SPAM DELETED What is the first exoplanet you would like to see an image of?

Can I ask, if anyone has considered, the Thomson opacity of the IGM, between earth and distant SNe Ia ? Yes, the CMB limits the opacity to a few percent at most, but even that would have non-trivial impact on calculated distances (and, so, indirectly, on the best-fit cosmological parameters, as compared to the "completely clear skies" benchmark Cosmology) ?

Hello, I'm a student working on serious games project and we're focusing on aurorae. Our game revolves around the player engineering a way for the solar wind to reach earth, and thus generating the lights, using extreme simplifications of physics. We wanted the player to use magnets to manipulate the solar wind, and so I have been trying to find out if an enormous human-made magnet could possible change the path of solar wind, or perhaps rather alter the magnetic field extended from the sun and affecting the wind that way.

Hi, can anyone help me, I need a soft copy for Cosmology by Jayant Narlikar 2nd or third edition Thanks

Here is an interesting thought, what if the bootes void is really the product of vacuum decay or collapse? and these voids we are seeing are product of the Higgs field dropping? had this ever been thought Or discussed?

HI!!! Great to be back.... This question of mine was inspired by a comment from Mordred in the Gravity thread.... Thoughts??

So I was asking the other day about fine constant structure and vacuum decay and got some answers. What I found goes against what I was told here, why? i have been looking more into this and found some more information. If the fine structure changes, then it's not actually a constant. If photons lose energy with expansion, then they are subject to time delays. So what I said for vacuum decay is possible the decay would be a quantum leap from one configuration to another. Whether it is reversible is another issue. it would also mean that acceleration of galaxies in distant sources tell us about the expansion in the past, so it may be that we can only tr…

Our best scientist claimed that a long time ago. Is this still true?

I hope this is following rules i just read about apep and how it is about to blow into a grb. It talks about being the biggest explosion since the Big Bang. i was under the impression grb’s have happened before. What makes this one the biggest since Big Bang and also what is the timeframe of it to blow? also I ask if I broke a rule please explain cause i am not sure why I keep getting my post trashed for rules if someone asks where I got my information am I not allowed to post the paragraph and article?

So been reading an article about brown dwarfs that were found. In the article it says In June 2018, citizen scientists flipping through the Backyard Worlds images noticed an unusual pairing: one object that appeared faint but moved fast--the telltale sign of a new brown dwarf--and another brighter object moving nearby and at the same rate. The Backyard Worlds science team was alerted and became immediately excited about this rare cosmic sighting. so question I have these are failed stars what is meant by moving? Are there wandering around the Milkey way? https://www.eurekalert.org/pub_releases/2020-02/amon-csd021120.php

https://en.m.wikipedia.org/wiki/HD_140283 how can this star be older than the universe? Also being that old how does it still exist surely it should be dying in not very long? also it’s only 200 lights years away from earth so closer than betelguese?

So what are your thoughts on the current state of Betelgeuse. Seems to be many ideas on it, last I read the dimming has slowed down?

https://www.google.ca/amp/s/www.syfy.com/syfywire/is-this-cosmic-sprinkler-surrounding-galaxys-next-gamma-ray-burst%3famp this looks rather scary. Poised to possibly cause a strong grb at any time and could possibly be the most powerful explosion since the Big Bang.

So I have noticed it’s about a week now everyday there is a new article from a different source about this. Not sure why it keeps making the news day after day as though there is something up with it we should know about. From what I have been told the constant of 1/137 may have changed and if it fell below 1 it can put the universe in universe in a vacuum decay state https://www.google.ca/amp/s/www.sciencealert.com/astronomers-have-found-an-ancient-galaxy-that-grew-fast-then-died-suddenly/amp

The moon always facing to Earth with same side. When Solar Eclipse the Sunlight will behind the moon. So if we put the artificial satellite and go behind the moon. What will be happend?

This is my return to the subject of quasar 3c186 in the topic "Hypervelocity Supermassive Black Hole." There are a few interesting facts I learned about this and if anyone knows something else, please say so. Some of this comes from this article: https://www.scientificamerican.com/article/gravitational-waves-send-supermassive-black-hole-flying/ 1 Two supermassive black holes, of different masses, merged in such a way to send it flying out of its' galaxy at 4.7 million miles per hour (1300 miles per second) or 0.7% light speed 2 The combined mass was estimated as three billion solar masses, according to this article: https://arxiv.org/pdf/1611.05501.pdf "..…

Hi. I've been in discussion with somebody and he claims to be a physicist/mathematician. I've asked him if he believes in a Flat or Sphere Earth (i don't btw).. and I honestly do not understand his answer (and it is leading me to suspect that he is lying about his career). This is what he says: I respond that I don't know what he means and if he can just answer with a yes or no, he replies: So i give up having to ask for a clarification and instead ask for an academic source/citation of some kind because I'll understand it if I see the source of his claim. He then scolds me that asking for a citation shows I can't comprehend what he …

According to current views, the Universe was created as a result of the explosion of an original singularity of infinitely small size and infinitely high density. This event, called the Big Bang, was to take place 13.7 billion years ago, as determined by the assumed expansion rate of the Universe, adopted by astronomers. The result of the Big Bang is also to be mysterious, undetectable dark matter (non-barionic) , which matter alleged to be the cause of the uniform velocity of stars in the disks of spiral galaxies. A computational analysis of the above issues presented in the Sagitarius BR program, available at the link: url deleted undermines both the occu…

If SpaceX Rocket Boosters run on Cryogenic Liquid Oxygen and Refined Petroleum 1 it just drives up the price of Petroleum while carrying with it a cryogenic storage system for whatever can get through its fuel seals while in space and the Chinese Long March series Rocket Boosters aren't that much different. The RP-1 Booster engines in the Falcon 9 uses RP-1 (alternately, Rocket Propellant-1 or Refined Petroleum-1) is a highly refined form of kerosene outwardly similar to jet fuel, used as rocket fuel. https://en.wikipedia.org/wiki/RP-1 Meanwhile the new generation of Long March rocket family, Long March 5, and its derivations Long March 6, Long March 7 will…

Do we have any way of taming or measuring the dark matter? If so what’s the simplest way to have it said?

https://www.space.com/hubble-constant-crisis-deepens.html See it takes a bigger man to say "I do not know" than it does to know the unknowable No One Can Agree How Fast Universe Is Expanding. New Measure Makes Things Worse. By Adam Mann 2020-01-09T20:37:47Z We just might need new physics to get out of this mess. HONOLULU — A crisis in physics may have just gotten deeper. By looking at how the light from distant bright objects is bent, researchers have increased the discrepancy between different methods for calculating the expansion rate of the universe. "The measurements are consistent with indicating a crisis in cosmolo…