Search Publications

New suprathermal proton population around the Moon: Observation by SARA on Chandrayaan-1

Barabash, Stas; Holmström, Mats; Futaana, Yoshifumi +4 more

We report a new population of suprathermal H⁺ (∼1.5-3 times the solar wind energy) around the Moon observed by Solar Wind Monitor (SWIM)/Sub-keV Atom Reflecting Analyzer (SARA) on Chandrayaan-1. These ions have large initial velocity (>100 km s^-1) and are observed on the dayside, near the terminator, and in the near-wake r…

HIP 21539 is not a past very close neighbour of the Sun

Panuzzo, P.; Sartoretti, P.; Soubiran, C. +3 more

Aims: A previous study claimed that the star HIP 21539 passed close to the Sun, at a distance of 1.9 pc, around 0.14 Myr ago. We show that this is not the case.
Methods: We redetermined the trajectory of the star relative to the Sun using a new accurate radial velocity from the HARPS spectrograph combined with the recent Gaia-TGAS astrom…

Social media and popularising space: Philae Lander (@Philae2014) and the journey to comet 67P/Churyumov-Gerasimenko

Ryan, Lorna

The popularisation of space activities is concerned with the public support of, interest in, and understanding of, the benefits to citizens of space science and space exploration. The media, traditional and new, play a significant role in popularising science. While scholars have acknowledged the potential of social media to support public engagem…

Local two-sample testing: a new tool for analysing high-dimensional astronomical data

Freeman, P. E.; Kim, I.; Lee, A. B.

Modern surveys have provided the astronomical community with a flood of high-dimensional data, but analyses of these data often occur after their projection to lower dimensional spaces. In this work, we introduce a local two-sample hypothesis test framework that an analyst may directly apply to data in their native space. In this framework, the an…

Far Infrared and Submillimetre Surveys: from IRAS to Akari, Herschel and Planck

Wang, Lingyu; Rowan-Robinson, Michael

On the signatures of flare-induced global waves in the Sun: GOLF and VIRGO observations

García, Rafael A.; Kumar, Brajesh; Mathur, Savita +1 more

Recently, several efforts have been made to identify the seismic signatures of flares and magnetic activity in the Sun and Sun-like stars. In this work, we have analysed the disc-integrated velocity and intensity observations of the Sun obtained from the Global Oscillations at Low Frequencies (GOLF) and Variability of solar IRradiance and Gravity …

Visibility of coronal mass ejections in SOHO/LASCO coronagraphs

Bronarska, K.; Michalek, G.; Yashiro, S. +1 more

We studied the detection efficiency of coronal mass ejections (CMEs) of the Large Angle Spectrometric Coronagraph (LASCO) on board the Solar and Heliospheric Observatory (SOHO). For this purpose LASCO/SOHO observations are compared with these obtained by the two Solar Terrestrial Relations Observatory (STEREO) satellites in quadrature in the perio…

Multi-label Learning for Detection of CME-Associated Phenomena

Yang, Y. H.; Xie, Z. X.; Peng, B. +2 more

Coronal mass ejections (CMEs) are considered as one of the driving sources of space weather. They are usually associated with many physical phenomena, e.g. flares, coronal dimmings, and sigmoids. To detect these phenomena, traditional supervised-learning methods assumed that at most one event occurred in a CME; therefore each CME instance is assoc…

AKARI Spectroscopy of Quasars at 2.5 - 5 µm

Nakagawa, Takao; Ohyama, Youichi; Im, Myungshin +5 more

Utilizing a unique capability of AKARI that allows deep spectroscopy at 2.5 - 5.0 µm, we performed a spectroscopy study of more than 200 quasars through one of the AKARI mission programs, QSONG (Quasar Spectroscopic Observation with NIR Grism). QSONG targeted 155 high redshift (3.3 < z < 6.42) quasars and 90 low redshift active galacti…

Gas emission and dynamics in the infrared dark cloud G31.23+0.05

Zhang, Chuan-Peng; Wang, Jun-Jie; Xu, Jin-Long +1 more

We performed a multiwavelength study towards the infrared dark cloud (IRDC) G31.23+0.05 with new CO observations from Purple Mountain Observatory and archival data (the GLIMPSE, MIPSGAL, HERSCHEL, ATLASGAL, BGPS and NVSS surveys). From these observations, we identified three IRDCs with systemic velocities of 108.36+/- 0.06 (cloud A), 104.22+/- 0.1…