Skip to content

Astronomy and Cosmology

Topics related to observation of space and any related phenomena.

  1. Started by scienceafrique,

    A young Scientist has gone ahead to explain the Mystery of why Uranus has Vertical Rings, rather than the horizontal rings seen in other ringed planets. In the early years of our solar system, protoplanets (bodies developing to become planets) collided in violent giant impacts that helped create the worlds we see today. Most researches hold the belief that Uranus’ spin was the result of a one of these collisions. While it is not yet possible to recreate planets in the lab and smash them together to see what happens, what Jacob and his team did was to create computer models simulating the events using a powerful supercomputer as the next best thing. LINK DEL…

    • 0

      Reputation Points

    • 3 replies
    • 1.1k views
    • 1 follower
  2. Lunar eclipse flash - electrical discharge "...a flash of light seen during totality has astronomers on the hunt for a new crater on the moon...." https://www.nationalgeographic.com/science/2019/01/meteor-hit-the-moon-during-blood-moon-eclipse-heres-what-we-know/ They will likely not find any new crater and here's why: It hit me early this morning: When sunlight hits the Moon's surface, the temperature can reach 260 degrees Fahrenheit (127 degrees Celsius). When the sun goes down, temperatures can dip to minus 280 F (minus 173 C) - pretty extreme. Typically, daytime on one side of the moon lasts about 13 and a half days, followed by 13 and a half night…

    • 0

      Reputation Points

    • 11 replies
    • 1.8k views
    • 1 follower
  3. Hello! Does it make sense for Black Holes to be the hottest things in the Universe? Since nothing escapes it, light included, we can't actually directly observe any data. But since energy equals heat and the incredible amount of mass and energy packed into them, wouldn't that make them the hottest things in the Universe? And a follow up question. IF we could see a Black Hole, what color would it be?

    • 0

      Reputation Points

    • 16 replies
    • 2.5k views
    • 1 follower
  4. Started by harlock,

    How much voltage'd can a Van de Graaff generator reach on the Moon? I mean...completely without air!

    • 0

      Reputation Points

    • 5 replies
    • 1.1k views
    • 1 follower
  5. 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 …

    • 0

      Reputation Points

    • 36 replies
    • 4.5k views
    • 3 followers
  6. Started by Edwina Lee,

    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?

    • 0

      Reputation Points

    • 1 reply
    • 953 views
    • 1 follower
  7. 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…

    • 0

      Reputation Points

    • 19 replies
    • 3.8k views
    • 4 followers
  8. Started by beecee,

    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 …

    • 0

      Reputation Points

    • 4 replies
    • 1.4k views
  9. Started by coffeesippin,

    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.

    • 0

      Reputation Points

    • 126 replies
    • 16k views
    • 4 followers
  10. Started by gib65,

    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…

    • 0

      Reputation Points

    • 3 replies
    • 1.2k views
  11. 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

    • 0

      Reputation Points

    • 0 replies
    • 705 views
  12. Started by AXdlv,

    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)

    • 0

      Reputation Points

    • 22 replies
    • 3.5k views
    • 2 followers
  13. Started by Moreno,

    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.?

    • 0

      Reputation Points

    • 10 replies
    • 1.8k views
    • 2 followers
  14. 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…

    • 0

      Reputation Points

    • 5 replies
    • 1.2k views
    • 1 follower
  15. 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

    • 0

      Reputation Points

    • 10 replies
    • 2.1k views
    • 3 followers
  16. 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?

    • 0

      Reputation Points

    • 5 replies
    • 1.6k views
    • 1 follower
  17. 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 …

    • 0

      Reputation Points

    • 3 replies
    • 918 views
  18. Started by Siyatanush,

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

    • 0

      Reputation Points

    • 14 replies
    • 2.1k views
    • 2 followers
  19. Started by GeeKay,

    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!

  20. Started by beecee,

    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…

    • 0

      Reputation Points

    • 2 replies
    • 991 views
  21. Started by Itoero,

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

    • 0

      Reputation Points

    • 30 replies
    • 4.8k views
    • 4 followers
  22. Started by MigL,

    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 ?

    • 0

      Reputation Points

    • 5 replies
    • 1.2k views
    • 1 follower
  23. 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…

  24. Started by mondeluz,

    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?

    • 0

      Reputation Points

    • 3 replies
    • 1.1k views
    • 1 follower
  25. Started by Moontanman,

    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?

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.