Abstract Coronal mass ejections (CMEs) are the largest type of eruptions on Sun and main driver severe space weather at Earth. In this study, we implement a force-free spheromak CME description within 3D magnetohydrodynamic simulations to parametrically evaluate successive interacting CMEs representative heliosphere. We explore CME–CME interactions for range orientations, launch time variations...

The Sun, as an active star, is the driver of energetic phenomena that structure interplanetary space and affect planetary atmospheres. effects Space Weather on Earth solar system increasing importance human spaceflight preparing for lunar Mars missions. This review focusing perspective relevant phenomena, coronal mass ejections (CMEs), flares, particles (SEPs), wind stream interaction regions (...

Coronal mass ejections (CMEs) can have a profound impact on the interplanetary medium and the near-earth environment. We discuss the feasibility of detecting coronal mass ejections at radio wavelengths with a groundbased instrument. In particular, we explore the possibility that a radio telescope employing Fourier synthesis imaging techniques can detect thermal bremsstrahlung emission from CMEs...

We studied the relationship between successive coronal mass ejections (CMEs) and a long-lived geomagnetic storm (LLGMS) by examining the 1998 May 4 event. Five successive CMEs from the same active region and four interplanetary shocks were found to be associated with this LLGMS. We investigated the effect of successive and interacting CMEs on the LLGMS.

In the present paper we report on the difference in angular sizes between radio-loud and radio-quiet CMEs. For this purpose we compiled these two samples of events using Wind/WAVES and SOHO/LASCO observations obtained during 1996-2005. It is shown that the radio-loud CMEs are almost two times wider than the radio-quiet CMEs (considering expanding parts of CMEs). Furthermore we show that the rad...

We perform the first kinematic analysis of a CME observed by both imaging and in situ instruments on board STEREO, namely the SECCHI, PLASTIC, and IMPACT experiments. Launched on 2008 February 4, the CME is tracked continuously from initiation to 1 AU using the SECCHI imagers on both STEREO spacecraft, and is then detected by the PLASTIC and IMPACT particle and field detectors on board STEREO-B...

A sudden depletion or intensity “dimming” of the X-ray corona sometimes accompanies a solar eruptive flare or coronal mass ejection (CME). We have identified a dimming that occurred just prior to a “halo” CME, observed on 1997 April 7 using the Soft X-ray Telescope (SXT) on Yohkoh. Halo CMEs are prime candidates for “space weather” effects. The dimming occurred in compact regions near a flare o...

Context. The transition of the magnetic field from the ambient magnetic field to the ejecta in the sheath downstream of a coronal mass ejection (CME) driven shock is analyzed in detail. The field rotation in the sheath occurs in a two-layer structure. In the first layer, layer 1, the magnetic field rotates in the coplanarity plane (plane of shock normal and the upstream magnetic field), and in ...

We present observations of the formation, propagation and decay of vortexshaped features in coronal images from the Solar Dynamics Observatory (SDO) associated with an eruption starting at about 2:30UT on Apr 8, 2010. The series of vortices formed along the interface between an erupting (dimming) region and the surrounding corona. They ranged in size from several to ten arcseconds, and traveled...