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Date: 08 Aug 2006 15:53:52
From: INBOX ASTRONOMY: NEWS ALERT
Subject: HUBBLE IDENTIFIES STELLAR COMPANION TO DISTANT PLANET (STScI-PR06-38)
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FOR RELEASE: 1:00 pm (EDT) August 8, 2006
Ray Villard
Space Telescope Science Institute, Baltimore, Md.
(Phone: 410-338-4514; E-mail: villard@stsci.edu)
David Bennett
University of Notre Dame, Notre Dame, Ind.
(Phone: 574-631-8298; E-mail: bennett@nd.edu or david_bennett@comcast.net)
PRESS RELEASE NO.: STScI-PR06-38
HUBBLE IDENTIFIES STELLAR COMPANION TO DISTANT PLANET
NASA's Hubble Space Telescope has for the first time identified the
parent star
of a distant planet (system name OGLE-2003-BLG-235L/MOA-2003-BLG-53L)
discovered in 2003 through ground-based gravitational microlensing.
Gravitational
microlensing occurs when a foreground star amplifies the light of a
background star
that momentarily aligns with it. Follow-up observations by Hubble in
2005 separated
the light of the slightly offset foreground star from the background
star. This allowed
the host star to be identified as a red dwarf star located 19,000
light-years away.
The Hubble observations allow for the planet's mass and the orbit from
its parent
red star to be determined. In this artist's concept, the rings and moon
around the gas
giant are hypothetical, but plausible, given the nature of the family of
gas giant planets
in our solar system.
To see and read more about this research on the Web, visit:
http://hubblesite.org/news/2006/38
The Hubble Space Telescope is an international cooperative project
between NASA and the European Space Agency. The Space Telescope Science
Institute is operated for NASA by the Association of Universities for
Research in Astronomy, Inc., Washington.
-end-
You are receiving this e-mail because you are subscribed to the
notifications whenever there is a new Hubble Space Telescope image,
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Date: 08 Aug 2006 23:45:35
From: Sam Wormley
Subject: Re: HUBBLE IDENTIFIES STELLAR COMPANION TO DISTANT PLANET (STScI-PR06-38)
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INBOX ASTRONOMY: NEWS ALERT wrote:
> FOR RELEASE: 1:00 pm (EDT) August 8, 2006
>
> Ray Villard
> Space Telescope Science Institute, Baltimore, Md.
> (Phone: 410-338-4514; E-mail: villard@stsci.edu)
>
> David Bennett
> University of Notre Dame, Notre Dame, Ind.
> (Phone: 574-631-8298; E-mail: bennett@nd.edu or david_bennett@comcast.net)
>
> PRESS RELEASE NO.: STScI-PR06-38
>
> HUBBLE IDENTIFIES STELLAR COMPANION TO DISTANT PLANET
Here is an actual preprint--free of the science writer's take.
The First DIRECT Distance Determination to a Detached Eclipsing Binary in M33
http://xxx.lanl.gov/abs/astro-ph/0606279
Authors: A. Z. Bonanos, K. Z. Stanek, R. P. Kudritzki, L.M. Macri, D. D. Sasselov,
J. Kaluzny, P. B. Stetson, D. Bersier, F. Bresolin, T. Matheson, B.J. Mochejska,
N. Przybilla, A.H. Szentgyorgyi, J. Tonry, G. Torres
Comments: 36 pages, 12 figures, accepted for publication in ApJ
We present the first direct distance determination to a detached
eclipsing binary in M33, which was found by the DIRECT Project.
Located in the OB 66 association at coordinates (alpha, delta)=
(01:33:46.17,+30:44:39.9) for J2000.0, it was one of the most
suitable detached eclipsing binaries found by DIRECT for distance
determination, given its apparent magnitude and orbital period.
We obtained follow-up BV time series photometry, JHKs photometry
and optical spectroscopy from which we determined the parameters
of the system. It contains two O7 main sequence stars with masses
of 33.4+/-3.5 Mo and 30.0+/-3.3 Mo and radii of 12.3+/-0.4 Ro and
8.8+/-0.3 Ro, respectively. We derive temperatures of 37000+/-1500 K
and 35600+/-1500 K. Using BVRJHKs photometry for the flux calibration,
we obtain a distance modulus of 24.92+/-0.12 mag (964+/-54 kpc),
which is ~0.3 mag longer than the Key Project distance to M33.
We discuss the implications of our result and the importance of
establishing M33 as an independent rung on the cosmological distance
ladder.
http://xxx.lanl.gov/pdf/astro-ph/0606279
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Date: 09 Aug 2006 02:54:23
From: Sam Wormley
Subject: Re: HUBBLE IDENTIFIES STELLAR COMPANION TO DISTANT PLANET (STScI-PR06-38)
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Sam Wormley wrote:
> INBOX ASTRONOMY: NEWS ALERT wrote:
>> FOR RELEASE: 1:00 pm (EDT) August 8, 2006
>>
>> Ray Villard
>> Space Telescope Science Institute, Baltimore, Md.
>> (Phone: 410-338-4514; E-mail: villard@stsci.edu)
>>
>> David Bennett
>> University of Notre Dame, Notre Dame, Ind.
>> (Phone: 574-631-8298; E-mail: bennett@nd.edu or
>> david_bennett@comcast.net)
>>
>> PRESS RELEASE NO.: STScI-PR06-38
>>
>> HUBBLE IDENTIFIES STELLAR COMPANION TO DISTANT PLANET
>
>
> Here is an actual preprint--free of the science writer's take.
>
>
> The First DIRECT Distance Determination to a Detached Eclipsing Binary
> in M33
> http://xxx.lanl.gov/abs/astro-ph/0606279
>
> Authors: A. Z. Bonanos, K. Z. Stanek, R. P. Kudritzki, L.M. Macri, D.
> D. Sasselov,
> J. Kaluzny, P. B. Stetson, D. Bersier, F. Bresolin, T. Matheson,
> B.J. Mochejska,
> N. Przybilla, A.H. Szentgyorgyi, J. Tonry, G. Torres
>
> Comments: 36 pages, 12 figures, accepted for publication in ApJ
>
> We present the first direct distance determination to a detached
> eclipsing binary in M33, which was found by the DIRECT Project.
> Located in the OB 66 association at coordinates (alpha, delta)=
> (01:33:46.17,+30:44:39.9) for J2000.0, it was one of the most
> suitable detached eclipsing binaries found by DIRECT for distance
> determination, given its apparent magnitude and orbital period.
>
> We obtained follow-up BV time series photometry, JHKs photometry
> and optical spectroscopy from which we determined the parameters
> of the system. It contains two O7 main sequence stars with masses
> of 33.4+/-3.5 Mo and 30.0+/-3.3 Mo and radii of 12.3+/-0.4 Ro and
> 8.8+/-0.3 Ro, respectively. We derive temperatures of 37000+/-1500 K
> and 35600+/-1500 K. Using BVRJHKs photometry for the flux calibration,
> we obtain a distance modulus of 24.92+/-0.12 mag (964+/-54 kpc),
> which is ~0.3 mag longer than the Key Project distance to M33.
> We discuss the implications of our result and the importance of
> establishing M33 as an independent rung on the cosmological distance
> ladder.
>
> http://xxx.lanl.gov/pdf/astro-ph/0606279
>
>
>
News of the Universe
An Older but Larger Universe?
http://www.astro.ucla.edu/~wright/cosmolog.htm#News
NOTE: URL includes links
Ohio State astronomers have measured a new precise distance to the
nearby galaxy M33 based on a spectroscopic eclipsing binary. Their
value is 15% larger than the old Cepheid based distance. By itself this
says nothing about the Hubble constant because M33 is so close to the
Milky Way that its radial velocity is dominated by random motions, not
the expansion of the Universe. But it could indicate that Cepheid
distances are incorrect by 15%.
If so, the Hubble constant would be smaller: about 62 instead of 72
km/sec/Mpc. But the claim in the OSU press release that "the universe
could be [...] 15 percent older" is incorrect. If the Hubble constant
is lower, then CMB anisotropy data require that OmegaM, the ratio of
the matter density to the critical density, be higher, so the vacuum
energy is lower, and the change in the age of the universe is
considerably smaller, as shown in graph at right [click on the graph to
enlarge] which shows the age vs. Ho for CMB consistent models as the
solid curve, and the 1/Ho behavior assumed by the OSU press release as
the dashed curve. So the Universe would not be 15% older but perhaps 7%
older.
The claim that the Universe would be 15% larger is partially incorrect.
Even though relatively nearby galaxies would be 15% further away the
actual size of the Universe would go from infinite (open) to finite
(closed) but very big, which is a smaller Universe. The distance to
distant quasars at redshift z=6 would increase by only 4%, and the
distance to the last scattering surface changes less than 0.5% because
this is what is fixed by the CMB.
CNN quoting space.com and John Johnson of the LA Times accepted the
press release's claims of a 15% older and larger Universe uncritically.
The real news is that a new method for precision distance measurements
has achieved its first result. It will be averaged in with other
methods used to calibrate the Cepheid period-luminosity relation and
lead to a few percent decrease in the Hubble constant.
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