Search Publications
Infall and Rotation Motions in the HH 111 Protostellar System: A Flattened Envelope in Transition to a Disk?
Lee, Chin-Fei; Reipurth, Bo; Mao, Yao-Yuan
We have mapped the central region of the HH 111 protostellar system in 1.33 mm continuum, C18O (J = 2 - 1), 13CO (J = 2 - 1), and SO (NJ = 56 - 45) emissions at ~3'' resolution with the Submillimeter Array. There are two sources, VLA 1 (=IRAS 05491+0247) and VLA 2, with the VLA 1 source drivin…
The Argentinean Patagonia and the Martian landscape
Pacifici, Andrea
Throughout the Cenozoic Era, the geological history of the Argentinean Patagonia was dominated by basaltic volcanism and glacial and periglacial environments. Several geological and geomorphological processes that concurred to the sculpting of the landscape of this area could have been similar to those responsible of the shaping of the Martian sur…
Is Vela Jr. a young supernova remnant?
Katsuda, Satoru; Mori, Koji; Tsunemi, Hiroshi
The supernova remnant RX J0852.0-4622 (or Vela Jr.) has been considered to be very young (∼680 yr) based mainly on the possible detection of a radioactive decay line of 44Ti whose lifetime is only ∼90 yr. Here, we report on expansion measurements of the northwestern rim of this remnant, based on XMM-Newton observations separated by 6.5 …
3D Coronal Structures and Magnetic Field During the Total Solar Eclipse of 29 March 2006
Druckmüller, M.; Hamid, R. H.; Ambrož, P. +1 more
The good quality of the observing sequence of about 60 photographs of the white-light corona taken during the total solar eclipse observations on 29 March 2006, in Al Sallum, Egypt, enable us to use a new method of image processing for enhancement of the fine structure of coronal phenomena. We present selected magnetic-field lines derived for diff…
The nature of the ASCA/INTEGRAL source AX J183039-1002: a new Compton-thick AGN?
de Rosa, A.; Bird, A. J.; Ubertini, P. +6 more
We report on the identification of the X/soft γ-ray source AX J183039-1002 detected with ASCA and INTEGRAL/IBIS. The source, which has an observed 20-100 keV flux of ~8.6 × 10-11 erg cm-2 s-1, is inside a diffuse radio supernova remnant (SNR) and is spatially coincident with a compact radio source. We analysed arch…
The Emission Measure of the Solar Lower Transition Region (2 × 104-2 × 105 K)
Landi, E.; Dammasch, I. E.; Feldman, U.
We analyze Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectra in the 750-790 Å wavelength range from 12 different solar regions on the disk to measure the thermal structure of the lower transition region (LTR). We considered four coronal hole (CH), four quiet Sun (QS), and four active region (AR) data sets observed by SUMER during…
The Origin of an Extended X-Ray Emission Apparently Associated with the Globular Cluster 47 Tucanae
Makishima, Kazuo; Nakazawa, Kazuhiro; Yuasa, Takayuki
Using the Suzaku X-ray Imaging Spectrometer, we performed a 130 ks observation of an extended X-ray emission, which was shown by ROSAT and Chandra observations to apparently associate with the globular cluster 47 Tucanae. The obtained 0.5-6 keV spectrum was successfully fitted with a redshifted thin thermal plasma emission model whose temperature …
High-Accuracy Near-infrared Imaging Polarimetry with NICMOS
Batcheldor, D.; Sparks, W.; Axon, D. J. +5 more
The findings of a nine-orbit calibration plan carried out during HST Cycle 15, to fully determine the NICMOS camera 2 (2.0 µm) polarization calibration to high accuracy, are reported. Recently Ueta et al. and Batcheldor et al. have suggested that NICMOS possesses a residual instrumental polarization at a level of 1.2%-1.5%. This would comple…
12C/13C Ratio in Ethane on Titan and Implications for Methane's Replenishment
Nixon, Conor A.; Jennings, Donald E.; Bjoraker, Gordon L. +6 more
The 12C/13C abundance ratio in ethane in the atmosphere of Titan has been measured at 822 cm-1 from high spectral resolution ground-based observations. The value, 89(8), coincides with the telluric standard and also agrees with the ratio seen in the outer planets. It is almost identical to the result for ethane on Titan found by the composite infr…
Modeling the response of the induced magnetosphere of Venus to changing IMF direction using MESSENGER and Venus Express observations
Boardsen, Scott A.; Gloeckler, George; Ho, George C. +14 more
The second MESSENGER flyby of Venus on 5 June 2007 provided a new opportunity to study the response of the induced magnetosphere of the planet to changes in the direction of the interplanetary magnetic field (IMF). At the time of the MESSENGER flyby, the European Space Agency's Venus Express spacecraft was located outside the magnetosphere and pro…