Astronomy and Astrophysics – Astronomy
Scientific paper
Apr 1998
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1998exdu.work..291u&link_type=abstract
Exozodiacal Dust Workshop, p. 291
Astronomy and Astrophysics
Astronomy
2
Michelson Interferometers, Astronomical Interferometry, Space Missions, Astronomical Photometry, Near Infrared Radiation, Stellar Envelopes, Active Galactic Nuclei, Infrared Imagery, Zodiacal Dust, Stellar Luminosity, Stellar Spectra
Scientific paper
The Space Interferometry Mission (SIM) is the next major space mission in NASA's Origins program after SIRTF. The SIM architecture uses three Michelson interferometers in low-earth orbit to provide 4 microarcsecond precision absolute astrometric measurements on approx. 40,000 stars. SIM will also provide synthesis imaging in the visible waveband to a resolution of 10 milliarcsecond, and interferometric nulling to a depth of 10-4. A near-IR (1-2 micron) capability is being considered. Many key technologies will be demonstrated by SIM that will be carried over directly or can be readily scaled to future Origins missions such as TPF. The SIM spacecraft will carry a triple Michelson interferometer with baselines in the 10 meter range. Two interferometers act as high precision trackers, providing attitude information at all time, while the third one conducts the science observations. Ultra-accurate laser metrology and active systems monitor the systematic errors and to control the instrument vibrations in order to reach the 4 microarcsecond level on wide-angle measurements. SIM will produce a wealth of new astronomical data. With an absolute positional precision of 4 microarcsecond, SIM will improve on the best currently available measures (the Hipparcos catalog) by 2 or 3 orders of magnitude, providing parallaxes accurate to 10% and transverse velocities to 0.2 km/s anywhere in the Galaxy, to stars as faint as 20th magnitude. With the addition of radial velocities, knowledge of the 6-dimension phase space for objects of interest will allow us to attack a wide array of previously inaccessible problems such as: search for planets down to few earth masses; calibration of stellar luminosities and by means of standard candles, calibration of the cosmic distance scale; detecting perturbations due to spiral arms, disk warps and central bar in our galaxy; probe of the gravitational potential of the Galaxy, several kiloparsecs out of the galactic plane; synthesis imaging of circumstellar disks around young stellar objects; imaging the narrow-line regions of AGNs in the optical; direct distance determination of a half dozen nearby spiral galaxies using rotational kinematics, thereby sidestepping reddening and metallicity issues in the calibration of distance estimators like Tully-Fisher; imaging exozodiacal dust disks (when operating in its nulling mode, SIM will be sensitive, at a distance of (beta) Pic (20 pc), to scales ranging from 0.2 to 5 AU).
No associations
LandOfFree
The Space Interferometry Mission 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 The Space Interferometry Mission, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Space Interferometry Mission will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1603791