Search Publications
Ionospheric plasma energization at Mars during the September 2017 ICME event
Bhardwaj, Anil; Thampi, R. Satheesh; Thampi, Smitha V. +2 more
During September 2017, the solar active region (AR) 12673 produced several flares and Coronal Mass Ejections (CMEs). On 10 September 2017, a stronger and wider CME was erupted from AR 12673, which was Mars-directed (max. vsw = ~840 km s-1 near 1.5 au). This ICME caused a major space weather event at Mars on 12-13 September. W…
On the unexpected geomagnetic storm on june 8, 2019, and the heliospheric current sheet effect
Augusto, C. R. A.; Navia, C. E.; de Oliveira, M. N. +1 more
A period of minimum magnetic solar activity (such as June 2019) favors the observation of rare solar transient events, which would otherwise be lost in the magnetic vortex during a period of maximum solar activity. In this paper, we show that the most plausible explanation for the origin of an unexpected geomagnetic storm on June 8, 2019, is a sma…
The water production rate of Rosetta target Comet 67P/Churyumov-Gerasimenko near perihelion in 1996, 2002 and 2009 from Lyman α observations with SWAN/SOHO
Schmidt, W.; Bertaux, J. -L.; Combi, M. R. +1 more
We report here the observations of the hydrogen cloud in Lyman alpha emission of Comet 67P/Churyumov-Gerasimenko at the last three passages through its perihelion, in 1996, 2002 and 2009. This comet became the target of ESA space mission Rosetta in 2003, and is therefore of particular interest. The data were collected with the SWAN instrument on b…
The Hohmann-Parker effect measured by the Mars Science Laboratory on the transfer from Earth to Mars: Consequences and opportunities
Frahm, R. A.; Wimmer-Schweingruber, R. F.; Christian, E. R. +33 more
We show that a spacecraft launched from Earth towards Mars following a Hohmann minimum energy transfer trajectory has a strong tendency to remain well-connected magnetically to Earth, in the early phase of the transfer, or to Mars in the late phase, via the Parker spiral magnetic field. On the return trip, the spacecraft would remain reasonably we…
On distribution of CMEs speed in solar cycle 23
Mittal, Nishant; Sharma, Joginder; Tomar, Vivek +1 more
We have analyzed the data for more than 12900 coronal mass ejections (CMEs) which were obtained by SOHO/LASCO during the period of 1996-2007. The online CME catalogue contains all major CMEs detected by LASCO C2 and C3 coronagraphs. Basically we determine the CME speeds from the linear and quadratic fits to the height-time measurements. It is foun…
A review of SOHO/UVCS observations of sungrazing comets
Bemporad, A.; Poletto, G.; Giordano, S. +1 more
In the last 10 years more than 1000 sungrazing comets have been discovered by the LASCO coronagraphs aboard SOHO the spacecraft; from this huge amount of data it has been possible to study the common origin of these comets and to explain some of the main peculiarities observed in their lightcurves. Moreover, the UV Coronagraph Spectrometer (UVCS) …
An overview of Jovian electrons during the distant Ulysses Jupiter flyby
Dalla, S.; Kunow, H.; Wibberenz, G. +9 more
Since the 1970's interplanetary electrons in the MeV energy range, of Jovian origin, have been extensively studied from close to the Sun to beyond the Kronian orbit, near the ecliptic. The Ulysses trajectory allowed to study the propagation of these particles, in a wide range of heliographic latitudes. The location of Jupiter with respect to the s…
A statistical study of the properties of interplanetary coronal mass ejections from 0.3 to 5.4 AU
Liu, Y.; Richardson, J. D.; Belcher, J. W.
We make a comprehensive survey of interplanetary coronal mass ejections (ICMEs) observed by the Helios 1 and 2, Ulysses, WIND and ACE spacecraft, which together cover heliocentric distances from 0.3 to 5.4 AU. The signatures used to identify ICMEs are enhanced helium abundances and depressed proton temperatures. We use the ICME list to study the r…
Coronal mass ejection of 4 April 2000 and associated space weather effects
Jadav, R. M.; Iyer, K. N.; Joshi, H. P. +1 more
The effects of a Halo Coronal Mass Ejection (CME) erupted on 4 April 2000 are studied and reported here. The effect of such CME on the interplanetary medium (IPM) is sensed by the Interplanetary Scintillation (IPS) recorded at Rajkot. The Solar Observations of this CME and associated events, like Solar Energetic Particles (SEP) and flare, are pres…
Recent advances in the long-wavelength radio physics of the Sun
Gopalswamy, N.
Solar radio bursts at long wavelengths provide information on solar disturbances such as coronal mass ejections (CMEs) and shocks at the moment of their departure from the Sun. The radio bursts also provide information on the physical properties (density, temperature and magnetic field) of the medium that supports the propagation of the disturbanc…