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    What's really down in a BH? (a Planck star)

    This is really fascinatingy We know of course black holes formed in the early universe, but is there enough time for a signal to get to us now? IS this signal strong enough and/or unambiguous enough to be able to detect with current technology? If we do detect it, I would think we are justified...
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    Stargazing Will the James Webb telescope see past the big bang?

    The Cmb was emitted 380k years after the big bang. Before that the universe was much like the surface of the sun i.e opaque. You can't see the interior of the sun just like you can't see before the Cmb was emitted with Em radiation. So getting a bigger better telescope isn't going to help...
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    Stargazing B mode detected by South Pole Telescope but its from gravitational lensing not primordial gravity waves so guess we are still waiting for those, but a good sign methinks.
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    Black hole acreting binary -magnetic fields

    Im thinking more of what happens to the material before it falls down the black hole. In white dwarf binaries for example it doesn't have to form an acretion disc. if there are strong magentici fields then the material infact wotn form an acretion disc but will travel along the field lines to...
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    Black hole acreting binary -magnetic fields

    Thanks Chronos, but is there a theory that's accepted? Normally when there is a strong magentic field the larger stars material can't cross the field lines and so does not form an acretion disc. Instead it gets tangled on the field lines and goes straight to the comapct star. But the black...
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    Black hole acreting binary -magnetic fields

    In a white dwarf acreting binary we would make distinction between thsoe with weak magnetic field that make an acretion disc and those with strong magentic fields where the material from the larger star gets funneled along the field lines. But in a black hole binary all of the energy is...
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    Nuetron Star Binary

    The acretion process between a white dwar binary and blakc hole binary is significantly different as the black hole has no solid surface. So am I right to presume that a neutron star binary should be the same process but with higher energies than than white dwarf case?
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    Bipolar outflow in protostars

    Found it: 10^7 years
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    Bipolar outflow in protostars

    How long does the bipolar outflow stage last in proto/T Tauri stars ?
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    What will Juice tell us about Europa?

    I think finding signs of life is the key issue rather than colonisation. As I understand it Europa gets more press due to the higher probability of interaction between the surface and the ocean this increases the odds for life and for us to find signs of that life. Also there's more energy...
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    What will Juice tell us about Europa?

    Now that ESa have selected Juice as its next main mission it seems dissapointing that the main target is Ganymede rather than Europa. I guess this is due to the extra cost of extra radiation shielding for Europa and due to the fact that NASa were supposed to do Europa as part of the original...
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    Which would you fund?

    Tricky one, I would pick Juice if was going to spend more time at Europa, Ganymede is a less exciting prospect. Athena looks cool but not sure it will discover anything fundametnally new. NGo, I am not sure the technology is reallyu ready. LiSA pahtfinder ahsnt even proven itself yet .
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    Unraveling the Mystery of ISM Dust: Origins & Categories

    Hi can anyone help : Are there different categories of ISM dust ? Where is the dust thought to have come from? Many thanks
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    Short burst GRB's

    Thanks a lot for that , i was trying to find what thhe evidence was but couldn't really find anything cocnrete, much appreciated.
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    Short burst GRB's

    Is there any actaul observational evidence that short burst GRB's are casued by neutron star mergers?
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    Calculating the output of Seyferrt Galaxy

    Im trying to calcuate the energy output of Saigtarius A star if it were to accrete material at the same rate as a typical Seyfert Galaxy which I understand to be about 1 solar mass per year (correct?). I am getting an answer that looks way too low. As I understand it we should get a number...
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    Ganymede, life and JUICE

    Are there any papers describing the possibility of life on Ganymede? I understand it is believed to have a liquid water ocean. But few seem as excited about Ganymede as they are about Europa. Is this becuase of the location of the ocean? If there are few or no prospects for lilfe on Ganymede...
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    Black hole complementarity and omnipresence

    As I understand black hole complementarity, two observers (one beyond the event horizon ,one within it) experience different realities. There is no contradiction because no one can observe both scenarios at once, you can't be inside and outside the event horizon, hence no contradiction. But...
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    Kepler22b-first exoplanet found in hab-zone of sun-like star

    As has beein pointed out Kepler uses Photometry and to get mass you need to use a kinematic technique ie radial velocity. I watched the press conference last night and they said they would be able to do the follow up radial velocity this summer. However not sure they meant start this summer or...
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    Astrobiology Missions, whats being proposed?

    Thanks I note the Wiki page usues the term " was a joint NASa ESA proposal", any diea why use the emphasis on the past tense? Is it not still an option for further development ( for a distant day when budgets are healthier) or has it been rejected ?
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    Astrobiology Missions, whats being proposed?

    There are a number of moons that seem to excite astrobiologists. Europa, Titan and Enceledus spring to mind. Are there any good resoruces that explore what missions are being seriously proposed to explore these moons in the future?
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    Best star for exoplanet

    What do you think is the best type to find planets in the habitabel zone? What do you think of the suggetsion of white dwarfs? any better suggestions?
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    High red shift galaxies

    How do high red shift galaxies differ from low red shift galaxies? Dow e see significant differences? if so what ?
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    Velocity of a star for Doppler Spectroscopy

    Im trying to solve back for Jupiters effect on the suns orbital velocity. I've looked up the asnwer and its 12.7 m/s and the formula I have for this is v = SQR (Gm*/r) where G is Grav constant M is the mass of the star (planets mass is...