|
|
Hipparcos News & Results |
|
ESA's
Hipparcos finds rebels with a cause
[October 2004]
|
A team of European astronomers has discovered that many stars in the vicinity of the Sun have unusual motions caused by the spiral arms of our galaxy, the Milky Way. According to this research, based on data from ESA's Hipparcos observatory, our stellar neighbourhood is the crossroads of streams of stars coming from several directions. Some of the stars hosting planetary systems could be immigrants from more central regions of the Milky Way. Further details can be found in the ESA Science News Release 23-2004 or in the article on this site. |
Hipparcos parallaxes and the distance to the Pleiades
[January 2004]
 |
The Pleiades "distance problem" was identified shortly after the publication of the Hipparcos Catalogue in 1997, and remains unresolved. Essentially, the mean cluster distance derived from a number of individual Hipparcos parallaxes is some 10% smaller than the distance determined through main-sequence fitting. A recent Nature paper (see Caltech Press Release) implies that the Hipparcos results are in error. The situation is not so clear-cut: see article on this web site. |
Star
Award for the Hipparcos web site
[June 2000]
 |
The Hipparcos Space Astrometry Mission web site has been selected to receive the Griffith Observatory Star Award for July 2-8 2000, for excellence in promoting astronomy to the public through the World Wide Web. |
Doubling the Hipparcos star count: the Tycho-2 Catalogue
[updated February 2000]
The Tycho-2 Catalogue, an astrometric and photometric reference
catalogue of the 2.5 million brightest stars on the entire sky, was
released on February 8th, 2000. The catalogue contains positions,
motions, brightness and colours for 2,539,913 stars, more than doubling
the number of stars in the original Tycho Catalogue. Details of how to
obtain the catalogue are available online. More general
information is available from the ESA
Science web site.
Scientific Preprints:
Recent preprints from the scientific literature are available from the
astro-ph
preprint server [external link] at sissa.it.
To obtain a list of Hipparcos related preprints from
the past 12 months retrieved directly from this server (Hipparcos
is passed as a search parameter in authors/title/abstract in the above search),
click
here [external link].
Scientific Abstracts:
An archive of published papers from most refereed journals is
maintained by the Astrophysics
Data System (ADS) [external link] at
Harvard. You can also access the Hipparcos related papers (using a
search for Hipparcos in the title and/or abstract) from the ADS
database via this table.
Hipparcos provides evidence for a Milky Way invasion
[updated
November 1999]
Astronomers from Leiden Observatory (in the Netherlands) and the
Max-Planck-Institut fur Astrophysik (in Munich, Germany) have used
Hipparcos proper motion data along with radial velocities and
photometric parallaxes to show that about ten per cent of the
metal-poor stars in the halo of the Milky Way come from a single
coherent structure that was disrupted during or soon after the Milky
Way formed. This research is published the November 4th (1999) issue
of Nature (Nature Vol. 402 pp53-55: Debris Streams in the solar
neighbourhood as relicts from the formation of the Milky Way by
A. Helmi et al). See also the ESA Science web site for more on this story.
Hipparcos Scientists awarded the
ESA Director of Science Medal
[updated
May 1999]
The first recipients of the ESA Director of
Science Medal were announced on 20th May 1999 in Bern, Switzerland. In
recognition of their outstanding contributions to the Hipparcos
mission, medals were awarded to Catherine Turon (Observatoire de
Paris-Meudon), Jean Kovalevsky (Observatoire de la Côte d'Azur),
Lennart Lindegren (Lund Observatory) and Erik Høg (Copenhagen
University Observatory). For further details on the awards see the ESA
Space Science report.
See also the press
release announcing these awards.
"Success Story - 30 Discoveries from
ESA's science missions in space": the Hipparcos contributions
[updated
May 1999]
A new brochure (May 1999) from the ESA Publications Division (reference ESA
BR-147) highlights a selection of discoveries from the European Space
Agency space science missions (from 1984 to 1999). The Hipparcos
mission figures prominently in the brochure, under the title
"Hipparcos-stars in 3D", with features on:
The brochure may also be viewed online at the ESA Space Science site.
Scientific
Results:
For recent reviews on the age of the Universe, distances to Globular
Clusters & the Large Magellanic Cloud and the RR Lyrae distance scale
see the Scientific Results page.
As scientists begin to delve into the goldmine of information contained in the Hipparcos and Tycho Catalogues, new scientific results covering areas as diverse as planetary ephemerides and stellar evolution theories will be forthcoming. Some miscellaneous early results from the Catalogues are described in the Scientific Results section. Proceedings from the HIPPARCOS Venice '97 symposium are now available on-line.
The Catalogues:
Details of the Hipparcos and Tycho Catalogues are given at the Catalogue page,
and these catalogues can now be
searched
online at this site.
Popular Science:
[updated
May1999]
In the June 1999 issue of Sky & Telescope read about how the
Hipparcos results are reshaping astronomy on many levels, in "Hipparcos:
The Stars in Three Dimensions"
Science magazine (February 13, 1998) features Hipparcos in the Research News section. (A summary is available at the SCIENCE Online site [external link].)
Check out Philip Morrison's commentary [external link] in the February 1998 issue of Scientific American [external link] (also in the February issue, p85).
Sky & Telescope (January 1998) features an article by Brian Skiff, showing how the publically available Hipparcos data helped unveil a well-known asterism's true character.
Many of the mainstream popular science magazines have also featured the Hipparcos mission and/or scientific results from the mission in their articles. A selection of references are available covering related science articles and radio and television features.
Education:
An education page introduces
the educational potential of the Hipparcos mission results.
We will be pleased to receive suggestions from teachers or
educators in astronomy about how such a service could be
improved.
ESA Publications:
In addition to publishing The Hipparcos and Tycho Catalogues, ESA publications
have also produced several other Hipparcos related
documents. A number of press-releases
and information notes have also been
issued by ESA regarding the Hipparcos mission.
|
|
Contact Us Last modified: Mon Feb 2 09:52:29 MET 2004 |
|
