Astronomy and Cosmology

What is your hunch about the following... If we could observe, from relative vicinity, a magnetar or some other neutron star that has a strong magnetic field - so that we are able to precisely track paths of compact objects closely encircling it or just making a close flyby - could we deduce, from paths of these object, whether the magnetic field curves the space or not (that is, if the magnetic field has mass-energy or not)? I am imagining that path of an object entering deeply into magnetic field of a magnetar would look differently if there is mass-energy in magnetar's magnetic field than if all mass-energy is only within the compact body of the magnetar. (I …

If a rock falls into our Sun, does it become a gas and mix with all the other gases? If so, the centre of the Sun should be a gas too. Could it be that the the magnetic lines that we see are at least caused by rocks falling into the Sun?

https://www.newscientist.com/article/mg24032022-600-exclusive-grave-doubts-over-ligos-discovery-of-gravitational-waves/ Exclusive: Grave doubts over LIGO’s discovery of gravitational waves """""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" Sensationalisitc headlines? My thoughts? Whatever the outcome, in my view it again supports the scientific methodology as superior to anything we have. I'll let those far more initiated in this sort of stuff to offer comments, rather then my own. Interesting to say the least. [Perhaps someone could E-Mail aLIGO or VIRGO for a comment?] https://arstechnica…

https://phys.org/news/2018-11-scientists-universe-mysteries.html How scientists are working together to solve one of the universe's mysteries November 27, 2018 by Emma Platts And Amanda Weltman, The Conversation An artist’s impression of fast radio bursts in the sky above the Australian SKA precursor, ASKAP. Credit: OzGrav, Swinburne University of Technology One of the most baffling puzzles of modern astrophysics is the nature of Fast Radio Bursts, which were discovered in 2007. These are seemingly rare, extremely bright flashes of light with radio wavelengths. They last only milliseconds; originate outside our galaxy, the Milky Way; come from regions …

The author: http://iqse.tamu.edu/people/cv/asvidzinsky.pdf The theory: http://iopscience.iop.org/article/10.1088/1402-4896/aa93a8/meta Submitted 2015, revised 2017.

I am told that scientists don’t know what happened within the first picosecond of the universe. If this is true, I have a question: How do they know it was a picosecond? I guess the assumption is that if you extrapolate the current expansion of the universe back to its origin, you don’t have to assume anything unusual in the first picosecond. But what if scientists could somehow see into the first picosecond? Is it possible that what they find is that it was way longer than a picosecond? In other words, the universe originally started expanding very slowly, and for the longest time didn’t grow much bigger than its original size, and then for some r…

Don't miss this on new years day! You can watch it on space.com. "At 12:33 a.m. EST (0533 GMT) on Jan. 1, New Horizons will zoom past the small object Ultima Thule, which lies 1 billion miles (1.6 billion kilometers) beyond Pluto" https://www.space.com/42859-new-horizons-ultima-thule-flyby-webcast-guide.html

Hi ! I need your help to find a formula to calculate the habitable zone of a star ... I searched and searched without having the answer ... I found this calculation: But it just defines a radius. I would like to calculate the lower limit of the ZH and its upper limit. I found other calculations with Boltzman's law, but I can not find results that work. So if you have an idea I'd be happy Thanks (sorry for my english)

Which astronomical event is associated with 1 January that we mark a New Year start from this date? Wouldn't it be more logical to mark it from 23 December when the daytime starts to increase? What do you think about possibility to shift it on 23 Dec.?

Hi, In a post in date of November 30 I find that the mass of ordinary matter [latex]M_b[/latex], could be determinate with the constants of the relativity (abstract's data planck 2018 used and data Planck 2015 also) : [latex] \Large {M_b = \frac{2c^2}{G\sqrt{\pi \Lambda} }}[/latex] values here 1.1056*10-52 m-2 and here 1.46*1053kg I know it's very surprising, we'll prefer to have the mass of dark matter in addition... You might think it's a coincidence. However we can do this other calculation [latex](M_b/2)*G*\Lambda *1 kg/1m^2 = 5.34*10^{-10} \text{ Joules /m^3}[/latex] and it's the density of the cosmological constan…

I would like to ask about the creation of matter with respect to the expanding universe.. I did some research and found a theory by Sir Jayant Narlikar: https://en.m.wikipedia.org/wiki/Steady_state_model His theory explains equilibrium of energy...with respect to creation of matter..... Hence i would like to hear your opinions and further increasing the discussion... Cheers

When a new planet or a star is discovered how do the scientists keep a track on their identities as there are billions of them?........(Just a question out of curiosity).....Does the observable universe keep on expanding....and if we can see more than 13.772billion light years(estimate) would that practically verify that the universe is expanding faster than light or is there anything else which proves it?

Firstly, I am new here, sorry if this was posted to the wrong thread. Upon seeing a statistic online that "if two baseballs were put in an empty vacuum only a meter apart they would collide in 3 days due to their own gravitational effect on each-other." I set out to firstly prove this was true and secondly to see if there was a relationship between this and something with the same radius, and distance from each other. So by using the equation G*[(m1*m2)/r2] =a I made a range of values for acceleration by varying the radius from 1 to 0.1 in graduations of -0.1 . Using the mass of a baseball as 0.145 Kg (therefore m1 & m2 = 0.145) and taking G as its known …

Do the forum members support the multi universe theory? Can you give your reason for whatever you believe to be true?

I am tying up the loose ends of a SF short story I wrote last year, featuring a neutron star. Right now, though, I'm stuck over a long-term problem concerning the star's luminosity. It's surface temperature is 8,200 K and has a diameter of 20 kms. My problem has consisted of trying (and failing) to calculate what the star's absolute magnitude would be. I'm afraid this is beyond my abilities to solve, and unfortunately I don't know anyone among my friends who has the mathematical nous to help me out here. So I would be extremely appreciative if someone here could put me out of my misery. Many Thanks!

https://phys.org/news/2018-12-scientists-biggest-black-hole-collision.html Scientists detect biggest known black-hole collision December 3, 2018, Australian National University An international team of scientists have detected ripples in space and time, known as gravitational waves, from the biggest known black-hole collision that formed a new black hole about 80 times larger than the Sun – and from another three black-hole mergers. The Australian National University (ANU) is playing a lead role in Australia's involvement with the gravitational wave discovery through a partnership in the Advanced Laser Interferometer Gravitational-wave Observatory (LIG…

What causes cosmological redshift? Can it be due to gravitation? (gravitational redshift)

Recently watched a movie called Alpha ( about a boy and his dog ), set in Europe 20,000 yrs ago. One scene shows the boy sleeping in a tree while the galactic firmament can be seen overhead. My night vision isn't that good, but I can't see the galactic plane in the Northern hemisphere, and I understand it is only visible in the Southern hemisphere. And I realize this is a movie ( pre-historic people with good teeth ? ) and certain artistic liberties may have ben taken, but is it possible that the attitude of the Earth, and Solar system, with respect to the galactic plane, has changed ( turned upside down ) during the last 20,000 years ?

Let’s assume that frequency is reduced by expansion of space. Then the energy of photon is reduced by E=hf. This is against the law of energy conservation. Though the energy of photon is small, but we have no reason why the law of energy conservation is destroyed. The law of energy conservation must be kept and the big bang theory was developed from it. In the big bang theory, it doesn’t need anything, for example energy, to obtain 1 m3 space. Space of 1 m3 is unconerned with energy so it cannot be replaced by the energy of one electron or all the energy in the universe. This means that though the energy of photon is small, but it should not be reduced by expansion of spa…

Keeping in mind that the multiverse is still an idea with no concrete proof, I would like to ask some simple questions about it. If multiverse is real. Does that mean that there is an infinite amount of universes with infinite possibilities? Like a universe where our fantasy becomes a reality, for example?

Is there a limit to how fast a black hole can spin? If not what if the black hole's spin rate exceeded the speed of light?

BH's by there very nature can never be seen directly, but their existence is near certain. If we are to deny the existence of BH's we must then explain in some other way the incredible effects on space and matter energy within their vicinity. see also....https://www.scienceforums.net/topic/117001-on-the-existence-of-black-holes/

I'm sure many will be interested in this article and the facts presented supporting GR as the current accepted and evidenced gravitational theory, that has passed all tests and made successful predictions. It appears it will be that way for a long time yet, as we are no closer to be able to formulate any QGT that can be validated.Despite my valuable time taken in presenting the following, I see it as necessary taking into account the many unscientific, unprofessional online criticisms of GR and the great man, by a diverse collection of lay people.https://phys.org/news/2018-01-gravitational-universe.html#jCpGravitational waves measure the universeJanuary 8, 2018, Harvard-S…

Recently in another thread on Philosophy, I had cause to question a claim made that BH's have been shown not to exist. Reasons were because Hawking Radiation had not been discovered and the Information/Firewall paradox. I replied how whether HR existed or not and irrespective of any information paradox, that BH's were well supported by evidence to exist and that the claims made were wrong and invalid. The person who denied their existence I'm sure was not really attuned to the history of BH's or any of the facts, and probably had only heard/read about them in a few pop science coverages in the daily media. His mispelling of Stephen Hawking's name as Hawkins lead me …

Hi All, I am trying to understand how we can show that the expansion of the universe is accelerating. I understand that one way is to use data taken from observing Type 1a supernovae due to their standard intrinsic luminosity. This then allows us to calculate luminosity distance and redshift, and from there calculate a ratio that apparently shows it to be non-linear over many samples taken at large distances. Wouldn't this just show that the expansion rate is changing? How do we specifically know it is accelerating? Have we ever observed a ratio that suggests the opposite? What I also do not understand is how we can know what the size of the universe was a…