Hinode Featured in Science

Dec. 07, 2007

National Astronomical Observatory of Japan, National Institutes of Natural Sciences (NAOJ/NINS)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA)
National Aeronautics and Space Administration (NASA)
Science and Technology Facilities Council (STFC)
European Space Agency (ESA)

Hinode (SOLAR-B) has brought us a new perspective of solar physics since its launch on September 22, 2006. Sience magazine, one of the leading journals of scientific research, features Hinode discoveries. An impressive picture obtained with Hinode appears in the front page of the journal. This press release highlights two of nine articles published in the special issue.

• Science Magazine Hinode Special Issue
  http://www.sciencemag.org/content/vol318/issue5856/

1. Continuous Plasma Outflows from the Edge of a Solar Active Region as a Possible Source of Solar Wind
   T. Sakao¹, R. Kano², N. Narukage,¹, J. Kotoku², T. Bando², E. E. DeLuca³ L. L. Lundquist³, S. Tsuneta², L. K. Harra⁴, Y. Katsukawa², M. Kubo⁵, H. Hara², K. Matsuzaki¹, M. Shimojo², J. A. Bookbinder³ L. Golub³, K. E. Korreck³, Y. Su³, K. Shibasaki², T. Shimizu¹, and I. Nakatani^{1
   1}Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA)
   ²National Astronomical Observatory of Japan, National Institutes of Natural Sciences (NAOJ/NINS)
   ³Harvard-Smithsonian Center for Astrophysics
   ⁴Mullard Space Science Laboratory (MSSL)
   ⁵High Altitude Observatory, The National Center for Atmospheric Research (HAO/NCAR)

Figure 1 presents an active region corona adjacent to an equatorial coronal hole observed with XRT/Hinode. The sequence of images display continuous plasma outflow from the edge of the active region (white curcle in Fig. 1). Apparent velocity of the outflow is 140 km/s. Magnetic field extrapolartion from full disk magnetogram suggests that roots of the open magnetic field are co- spatial with the plasma outflow region. Hinode allowed us to identify the source region of the low speed solar wind for the first time. This discovery will contribute to the study of solar wind which affects terrestrial environment.

• Movie [Pseudo-color] (JAXA/NAOJ)

• Close-up Movie [Pseudo-color] (JAXA/NAOJ)

© JAXA/NAOJ
Figure 1. The corona of active region adjacent to a coronal hole, seen by XRT/Hinode. A circle in the bottom indicates the size of the Earth.

2.Coronal Transverse Magnetohydrodynamic Waves in a Solar Prominence
T. Okamoto¹, S. Tsuneta¹, T. E. Berger², K. Ichimoto¹, Y. Katsukawa¹,B. W. Lites³, S. Nagata⁴, K. Shibata⁴, T. Shimizu⁵, R. A. Shine², Y. Suematsu¹, T. D. Tarbell², and A. M. Title^2
1National Astronomical Observatory of Japan, National Institutes of Natural Sciences (NAOJ/NINS)
²Lockheed Martin Solar and Astrophysics Laboratory (LMSAL)
³High Altitude Observatory, The National Center for Atmospheric Research (HAO/NCAR)
⁴Kwasan and Hida Observatories, Kyoto University
⁵Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA)

Figure 2 displays a limb prominence above an active region observed with SOT/Hinode. Prominences are floating cool plasma in the hot corona. High resolution images in Ca II H spectral line revealed waving motion of the prominence. Detailed analysis proved that the motion is attributed to Alfvén wave in the corona. This observational result holds vital clues for understanding the coronal heating.

• Movie [Pseudo-color] (JAXA/NAOJ)

© JAXA/NAOJ
Figure 2. Alfvén wave in the active region prominence observed by SOT/Hinode. A circle in the left indicates the size of the Earth.