Solar System Observing Opportunities D. Christian (CSUN), C. Lisse, A. Ptak, S. Murray (JHU), S. Wolk (CXC). WFXT Mission Synopsis.
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Solar System Observing Opportunities
D. Christian (CSUN), C. Lisse, A. Ptak, S. Murray (JHU), S. Wolk (CXC)
WFXT Mission Synopsis
One high resolution, high collecting area and wide FOV soft X-ray telescope with low background to image at least ½ the 0.4 – 7.0 keV sky down to very low fluxes while characterizing the spectra of millions of x-ray sources.
Key Scientific Parameters
Constant PSF (5” goal HEW) across 1o x 1o FOV
Effective Area ~ 15 x Chandra @ 1 keV (goal 10,000 cm2)
Bandpass ~ 0.4 – 7 keV; Analog to SSDS in X-ray band
Dedicated 2 year survey mission (no GO program)
Calibrated data products released with no proprietary period
Detailed PtSrc and Extended Object Catalogues
Discovery and Characterization of Groups & Clusters
Evolution of AGN Population
Star Forming Galaxies
Super Nova Remnants
Compact Galactic Objects
Solar System Objects & Nearby Stellar Neighborhood
The proposed WXFT mission will be performing 3 deep wide field surveys of 20000 sq. deg., 3000 sq. deg. and 100 sq. deg. that will include repeated observations and detections of foreground solar system objects throughout the course of the mission. WFXT will thus be a bonanza for solar system x-ray astrophysics. Understanding local soft x-ray emission processes, driven by scattering of solar x-rays and charge exchange with the solar wind, means understanding the nearest, best example of a stellar wind throughout interplanetary space; understanding the coupled neutral outflows from Io and their coupling to the rapidly rotating Jovian dynamo; understanding the influx and outflow of ISM H and He through the heliosphere; and understanding emission from the local hot bubble in the nearby ISM, surrounding the heliosphere.
RASS Solar System, Chandra ACIS Pointed Obs
WFXT’s sensitivity and angular scale allows for vastly improved solar system studies.
Bhardwaj, Lisse, et al. 2007 & Encyclopedia of the Solar System II, 2008
Known Solar System X-rays Emitters
New Possibilities with WFXT : Mercury, Uranus/Neptune? High Latitude & Main Belt Comets? Trojan Asteroids? Active Centaurs? The Heliopause?
Some of the currently known sources of X-rays in the Solar System. The complete list incl‘s the Sun, Planets, Comets, Moons, the Io Flux Torus, and the Heliosphere itself. [See excellent review by Bhardwaj, Lisse, et al. 2007 and ESS 2008]
Potential of a WFXT Solar System Survey:
Serendipitous Comet Detections in the RASS
Dennerl et al. 1997
C/Levy, Sept 1990
C/Levy, Jan 1991
C/Levy, Jan 1991
RASS detected 7 comets in 8 months down to a limit of 10-13 erg cm-2 sec-1. Based on the WFXT projected sensitivity and sky coverage, our cometary XLF, and the supply of short (~40) and long (~70) period comets reaching perihelion every year, we estimate at least 40 comet detections in the WFXT wide survey alone, tripling the number of comets seen in the x-ray. More comet detections will be found from observations of Main Belt Comets, Sungrazing comets, & Active Centaurs.
C/T-K, Nov 1990
C/T-K, Jan 1991
45P/HMP, Jul 1990
C/Arai, Nov 1990
flux ratios of all observed comets:
hot, fast, disturbed
O VIII / O VII
Chandra spectra of comets suggest different emission characteristics as the solar wind varies
C+N ~ O VII
low abundance of highly charged oxygen cold wind
high abundance of highly charged oxygen hot wind
O VIII / O VII flux increases
Bodewits et al. 2007
WFXT Planetary Observation Capabilities: SWCX Processes in the Earth’s GeoCorona.
Detection of heavy neutral atoms in the Earth’s magneto- sphere implies interaction of the extended cold H envelope of the Earth with the solar wind via CXE.
N.B. - SWCX more important than Jeans
escape for terrestrial H loss budget!
- Atmosphere Explorer C 1974
- Arecibo Incoherent Scatter Radar of e- and
neutral H abundances (Maher and Tinsley 1977)
- IMAGE/LENA observations of magnetosheath
quiescent solar behavior (Collier et al. 2001)
- IMAGE/HENA - CME response (Brandt 2001)
0.25 – 4.0 keV
WFXT Planetary Observation Capabilities: Venus Disk + Exosphere
Venus’ emission Is
dominated by a large
component due to
Its proximity to the
0.4 – 0.9 keV
GOES-7, 8, 10, 12
1.6 – 12.4 keV
Dennerl et al. 2008
WFXT Planetary Observation Capability:
X-ray images of Mars in individual emission lines
Dennerl et al. 2009
Emission in crescent
offset towards the Sun.
Emission above and below
Poles (!?) or in limb-effect
Major science question : what, if any, is the effect of Martian weather
(winter/summer, dust storms, etc.) on the x-ray emission?
Io, Europa, Ganymede, and the Io Plasma Torus have been marginally detected in the X-ray. Does the IPT provide the S, O atoms for Jupiter’s Polar X-ray emission? Need simultaneous map of whole system!Have we detected the root of Europa’s Neutral Atom Torus (Mauk et al. 2003)?
Cravens et al. 2002
WFXT can map instreaming neutral HI, HeI ISM emitting SWCXE xrays in the Heliosphere
Koutroumpa et al.
WFXT all-sky, long term monitoring capability critical to finding the SWCXE spectral signature in heliospheric
XMM RGS, Snowden et al. 2004
McCammonet al. 2002
ACIS-S Lunar night-side emission, Wargelin et al. 2004 (see also Wargelin et al. 2009 Chandra posters @