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It looks like you're using an Ad Blocker. Please white-list or disable AboveTopSecret.com in your ad-blocking tool. Thank you. Some features of ATS will be disabled while you continue to use an ad-blocker. I thought I did. A million degree atom hits your wrist. Another one hits your ankle. Those two atoms that hit your wrist and ankle don't keep the rest of you warm. Originally posted by watchitburn reply to post by Arbitrageur Can you explain that in a way that stupid people can understand it. Or provide a link to an explanation. Because right now, my brain doesn't want anything to do with what you just posted. The temperature of outer space varies, but the value does not matter much because the amount of matter sustaining it (and therefore, of energy involved) is tiny. See preceding question here, or www.phy6.org... The moment a massive body (like your own) touches the rarefied gas of outer space, it and not the gas will determine the heat flow around it. "If a astronaut were to step out of the space station wearing nothing but a t-shirt and jeans," I suspect he would first choke (all the air will escape his/her lungs) and then after a while he/she would end up freeze-dried, as all water would also evaporate from the body. Museums sometimes freeze-dry the carcasses of small mammals by suspending them in a vacuum chamber. Needless to say, I don't encourage the experiment. "The amount of mass that we derive matches very well with what we see -- stars, dust and gas -- in the region around the Sun," team leader Christian Moni Bidin of Chile's University of Concepcion said in a press release. "But this leaves no room for the extra material -- dark matter -- that we were expecting. Our calculations show that it should have shown up very clearly in our measurements. But it was just not there!" He added: "Despite the new results, the Milky Way certainly rotates much faster than the visible matter alone can account for. "So, if dark matter is not present where we expected it, a new solution for the missing mass problem must be found. Our results contradict the currently accepted models. The mystery of dark matter has just become even more mysterious." But even with an estimated mass anywhere between 10 billion and 60 billion Suns, the density of the halo at that scale is still so low that any similar structure around other galaxies would escape detection. Still, the presence of such a large halo of hot gas, if confirmed, could reveal where the missing baryonic matter in our galaxy has been hiding — and possibly hint at the true nature of dark matter throughout the Universe. Originally posted by jonnywhite reply to post by watchitburn An interesting quote from the linked article in the OP: But even with an estimated mass anywhere between 10 billion and 60 billion Suns, the density of the halo at that scale is still so low that any similar structure around other galaxies would escape detection. Still, the presence of such a large halo of hot gas, if confirmed, could reveal where the missing baryonic matter in our galaxy has been hiding — and possibly hint at the true nature of dark matter throughout the Universe. What this implies is that if other galaxies have something like this, it's not currently detectable. That's how it might explain, to some extent, the missing mass problem. Originally posted by watchitburn reply to post by XPLodER Awesome. Thanks for sharing that. There is always someone on this site knowledgeable in any subject matter brought up. Do you have a theory on what is causing the halo in the article? Any speculation will be welcomed. Originally posted by theDarthvader Xploder, I know this is one of your areas of expertise, could you how explain how you think this links to your bubbles / lens theory? Is it possible that this huge halo is impacting on our view of the wider universe? Or is it too diffuse? I was thinking that surely a structure this big could affect our measurements and calculations of distances and expansion of the universe? What are your thoughts on this? Could the halo distort our viewpoint, and therefore calculations? What if the halo was expanding or contracting, would that make a difference? Or is it completely irrelevant to our current theories? particularly regarding the expansion of the universe, redshift etc.
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Nova, dosad najpreciznija istraživanja kretanja zvijezda u Mliječnom putu nisu otkrila očekivane tragove većih količina tamne tvari u okolini Sunca, javljaju znanstvenici Europske južne promatračnice (ESO) Prema općeprihvaćenim teorijama, naše zvjezdano susjedstvo trebalo bi biti puno tamne tvari, misteriozne nevidljive supstance koja se može otkriti samo po gravitacijskom utjecaju na okolna tijela. Međutim, tim astronoma iz promatračnice u Čileu otkrio je da promatranja jednostavno ne podržavaju teorijska predviđanja. To znači da je teško očekivati da će pokušaji da se izravno otkriju čestice tamne tvari na Zemlji biti uspješni. Međunarodni tim stručnjaka u svojoj je novoj studiji mjerio kretanje više od 400 zvijezda udaljenih do 13.000 svjetlosnih godina od Sunca uz pomoć 2,2-metarskog ESO-ovog teleskopa promatračnice La Silla te drugih teleskopa. Na temelju prikupljenih podataka astronomi su izračunali mase materijala u blizini Sunca u prostoru četiri puta većem od svih koji su prije toga razmatrani. 'Količina mase koju smo zabilježili u području oko Sunca odgovara onome što vidimo – zvijezdama, prašini i plinovima', rekao je voditelj istraživanja Christian Moni Bidin i dodao: 'No to ne ostavlja prostora za dodatnu materiju – tamnu tvar, koju smo očekivali otkriti. Prema našim proračunima ona se u našim mjerenjima trebala vrlo jasno pokazati. Međutim, jednostavno je nema.' Tamna tvar je misteriozna materija koju nije moguće vidjeti, međutim, otkriva se kroz gravitacijski utjecaj na okolne materijale. Njezino postojanje pretpostavljeno je kako bi se našao odgovor na pitanje zašto vanjski dijelovi galaksija, uključujući i našu, rotiraju tako brzo. Naime, ako u galaksijama nema tamne tvari koja bi gravitacijom trebala držati zvijezde na okupu, one bi se zbog centrifugalne sile u brzim rotacijama trebale razletjeti svemirom jer gravitacija vidljive tvari nije dovoljna da to spriječi. Tamna tvar je posljednjih godina također postala ključnom komponentom teorija koje objašnjavaju nastanak i razvoj galaksija. Znanstvenici danas prihvaćaju ideju da tamna tvar sačinjava oko 80 posto ukupne mase svemira, unatoč tome što njezina priroda do sada nije razjašnjena. Sva dosadašnja nastojanja da se u laboratorijima na Zemlji otkrije tamna tvar bila su neuspješna. Prema postojećim modelima formiranja i rotacije galaksija, Mliječni put bi trebao biti okružen svojevrsnom aureolom tamne tvari. Oni ne mogu precizno predvidjeti kakav bi oblik ta aureola trebala imati, ali očekuje se da bi u blizini Sunca trebalo biti dosta velikih količina tamne tvari. Međutim, rezultati nove studije, odnosno nedostatak tamne tvari, pokazuje da bi aureola mogla imati samo neki vrlo neočekivani oblik – primjerice izuzetno izduženi. 'Unatoč našim rezultatima, činjenica je da Mliječni put rotira mnogo brže nego što bi to mogao da je sastavljen isključivo od vidljive tvari. Dakle, ako se tamna tvar ne nalazi ondje gdje smo očekivali, trebat će otkriti nova rješenja za problem nedostatka mase. Naši su rezultati u suprotnosti s trenutno prihvaćenim modelima. Misterij tamne tvari upravo je postao još misteriozniji. Buduća istraživanja, uključujući i ESA-inu misiju Gaia, bit će presudna za ostvarenje pomaka na ovom putu', zaključio je Christian Moni Bidin. - Sviđa vam se članak? Preporučite ga prijateljima putem ovih servisa: Pošaljite mailom