Other
Scientific paper
Jul 2000
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000hst..prop.8747s&link_type=abstract
HST Proposal ID #8747
Other
Hst Proposal Id #8747 Cosmology
Scientific paper
Recent determinations of the distance to a spiral galaxy NGC 4258 have sparked another controversy which could potentially have a significant impact on the entire extragalactic distance scale. A geometric distance from the observations of masers in this galaxy yields a distance of 7.2+/- 0.3Mpc {Herrnstein et al. 1999}, while HST/WFPC2 Cepheid observations lead to a distance of 8.1 +/- 0.4 Mpc {Maoz et al. 1999}; the two estimates are discrepant at the 2Sigma level. If the maser distance, which is independent of intermediate rungs in the distance scale ladder, is correct, then there appears to be a need to modify the Cepheid distance scale which has been serving as the foundation of the extragalactic distance scale. The goal of this Archival Proposal is to re-analyze the WFPC2 data obtained for the Cepheid study, and obtain a deep I-band luminosity function from a combined image, from which the distance will be estimated using the tip of the red giant branch {TRGB} method. The TRGB method is a Population II distance indicator, completely independent from the Cepheid distance scale, providing an independent check on the distance to NGC 4258.
No associations
LandOfFree
A Broken Rung on the Distance Scale Ladder? - The Case of NGC 4258 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A Broken Rung on the Distance Scale Ladder? - The Case of NGC 4258, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Broken Rung on the Distance Scale Ladder? - The Case of NGC 4258 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1720456