HST and 'dark matter' |
HST and 'dark matter' |
Guest_PhilCo126_* |
May 11 2007, 05:13 PM
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Guests |
ASA Updates Plans for Hubble 'Ring Of Dark Matter' Briefing
GREENBELT, Md. - NASA will hold a media teleconference at 1 p.m. EDT on May 15 to discuss the strongest evidence to date that dark matter exists. This evidence was found in a ghostly ring of dark matter in the cluster CL0024+17, discovered using NASA's Hubble Space Telescope. The ring is the first detection of dark matter with a unique structure different from the distribution of both the galaxies and the hot gas in the cluster. The discovery will be featured in the June 20 issue of the Astrophysical Journal. |
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Jun 12 2007, 01:41 AM
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#2
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Member Group: Members Posts: 723 Joined: 13-June 04 Member No.: 82 |
The wedding ring of MOND and non-exotic dark matter
The lensing mass reconstruction of the rich galaxy cluster Cl0024+17 has been argued to have revealed a ringlike dark matter structure that is offset from both the gas and the galaxies in the cluster. This has been claimed to be hard to explain in the framework of modified Newtonian dynamics (MOND). We aim to check that claim, taking into account the old-known mass discrepancy of galaxy clusters in MOND, which can be resolved by, e.g., adding a component of 2 eV neutrinos. For that purpose, we derive an upper limit to the density of matter in the ring, and compare it to the Tremaine-Gunn limit on the density of neutrinos. We conclude that the maximum density of matter in the ring is two sigmas below the Tremaine-Gunn limit, and that the ringlike structure in Cl0024+17 does not pose a new challenge to MOND. No surprise here. As always, the overblown claims that the 'Dark Matter' theory has been proven correct by the latest observation are shown to be mistaken. I was expecting a paper like this to appear (as you can probably tell from my earlier posts on this, and other threads). Not that this refutation will be anywhere near as well-publicized as the original claim. Bill |
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Lo-Fi Version | Time is now: 27th September 2024 - 05:48 AM |
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