Related papers: Discovery of X-rays from Mars with Chandra
We report Chandra and XMM-Newton observations of the transient neutron star low-mass X-ray binary GRS 1741.9-2853. Chandra detected the source in outburst on 2000 October 26 at an X-ray luminosity of ~10^{36} erg/s (2--8 keV; 8 kpc), and in…
Hard X-ray emissions from a Herbig Be star MWC297 were discovered in three separate observations spanning 5 days in April 1994 with the Advanced Satellite for Cosmology and Astrophysics (ASCA). An X-ray flare was found at the beginning of…
On July 25 2017 a multi-step Forbush decrease (FD) with the remarkable total amplitude of more than 15\% was observed by MSL/RAD at Mars. We find that these particle signatures are related to very pronounced plasma and magnetic field…
The BL Lacertae object PKS 2155-304 was observed by the Infrared Space Observatory in May and June 1996, during a multiwavelength campaign. These are the first observations in the mid- and far-infrared bands since IRAS. In the observing…
The narrow-line Seyfert 1 galaxy (NLS1) IRAS 13224-3809 has been observed with the CHANDRA High Resolution Camera (HRC-I) for 12 ksec on February, 2, 2000. The source was proposed for CHANDRA observations to precisely determine the X-ray…
We present Chandra X-ray observations of 14 radio-loud quasars at redshifts $3 < z < 4$, selected from a well-defined sample. All quasars are detected in the 0.5-7.0 keV energy band, and resolved X-ray features are detected in five of the…
Using the Chandra ACIS-I instruments, we have carried out the deepest X-ray observation on a typical Galactic plane region at l 28.5 deg, where no discrete X-ray sources have been known previously. We have detected, as well as strong…
We show with a short Chandra HRC-S exposure that the powerful X-ray source coincident with the nucleus of M33 is unresolved at the highest spatial resolution available to date (0"4). The source flux is variable, doubling during the 5 ks…
X-ray observations of galaxies have grown from a curiosity into a full-fledged field of astronomy. These observations provide unique information on black holes, binary stars, and the hot phase of the ISM, which can be used to constrain the…
A deep (98.2 ks) Chandra Cycle-1 observation has revealed a wealth of discrete X-ray sources as well as diffuse emission in the nearby face-on spiral galaxy M101. From this rich dataset we have created a catalog of the 110 sources from the…
NASA's Chandra X-ray Observatory and ESA's XMM-Newton made their first observations one decade ago. The unprecedented and complementary capabilities of these observatories to detect, image, and measure the energy of cosmic X-rays, achieved…
To help constrain the origin of the peculiar X-ray emission of gamma Cas stars, we conducted a simultaneous optical and X-ray monitoring of pi Aqr in 2018. At that time, the star appeared optically bright and active, with a very strong…
Jupiter, Saturn, and Earth - the three planets having dense atmosphere and a well developed magnetosphere - are known to emit X-rays. Recently, Chandra X-ray Observatory has observed X-rays from these planets, and XMM-Newton has observed…
We present the results of a 17 ks Chandra ACIS-S observation of the nearby dwarf spiral galaxy NGC 4395. Chandra affords the first high-quality, broadband X-ray detection of the active nucleus of this object that is uncontaminated by nearby…
From October 1999 to August 2002, 45 transient X-ray sources were detected in M31 by Chandra and XMM-Newton. We have performed spectral analysis of all XMM-Newton and Chandra ACIS detections of these sources, as well as flux measurements of…
By June of 2020, the extended ROentgen Survey with an Imaging Telescope Array (eROSITA) on board the Spectrum Roentgen Gamma observatory had completed its first of the planned eight X-ray all-sky survey (eRASS1). The large effective area of…
We present X-ray imaging spectroscopy of the extremely luminous infrared galaxy IRAS 09104+4109 (z=0.442) obtained with the Chandra X-ray Observatory. With the arcsec resolution of Chandra, an unresolved source at the nucleus is separated…
We present a comprehensive analysis of the X-ray observations obtained from \xmm\, and \chandra\, for a sample of bona-fide Compact Symmetric Objects (CSOs) to investigate their X-ray emission properties. Ultimately, we obtain 32 effective…
The past decade has seen a large progress in the X-ray investigation of early-type galaxies of the local universe, and first attempts have been made to reach redshifts z>0 for these objects, thanks to the high angular resolution and…
CAL 83 was one of the first supersoft X-ray binaries to be discovered and is considered to be the prototype of its class. In 15 X-ray observations between 1983-1997 it was observed to have nearly constant X-ray luminosity and temperature,…