Black-light flares in He I D3
Moreton waves and filament oscillations
From 1969 to 1995, Big Bear Solar Observatory (BBSO)
recorded all observations on 35 mm films before its post-1995 switch to
digital imaging. The film data include full-disk Hα
observations from its 8 inch telescope and high-resolution observations
in Hα and He I D3 from its 10 and 26 inch
telescopes. The cadence of data ranges from about 10 s to 1 minute.
BBSO has an excellent clear sky fraction. These film data covering two and half solar cycles
span the operational service period of several space missions (e.g.,
SMM, CGRO, and Yohkoh). Public access to the film data was difficult
and their scientific capability has far from been fully explored.
Supported by NSF, this project aims to digitize BBSO films using
specialized commercial digitizing equipment and archive them in the
public domain. The BBSO data to be digitized includes full-disk and
selected high-resolution H-alpha and He I images. The entire set of
film data will be converted to create a synoptic data base. With a
supplement funding from NASA, we will also digitize full-disk Hα images from 1963 to 1997 obtained by National Solar Observatory
(NSO) at Sacramento Peak, which are complementary to BBSO data in
coverage and with its off-band observations. The observed solar flares
and filament eruptions will be automatically detected and cataloged
using artificial intelligence methods that have been developed and
implemented at the Space
Weather Research Laboratory of the New Jersey Institute of Technology.
The digitized solar images may not be suitable for accurate
photometric analysis due to the nonlinear intensity response of films.
Nevertheless, morphological study on solar features (e.g., filament
activities and flares) can be carried out after applying standard image
processing techniques. The rich film data
base contains many unique events that challenge our
understanding. Importantly, the long-term coverage and high quality of
the BBSO/NSO film data plus the digital data from our Global Halpha
Network will have very broad applications for statistical analyses,
such as the cycle variation of solar activities. The study of a
large number of archived events has promise to improve the forecasting
of future solar eruptive events, and thus assist operational space
Current project progress: We have finished digitizing all
the full-disk BBSO and NSO Hα films, and
about 70% of high-resolution BBSO films. In total, over 40 million
images have been archived.
Quick-look movies and images are now released via a searchable data catalog, based on which
users can make data requests.
We have also obtained some significant results using the film data. We welcome your
suggestions/comments, and please also contact us if films of your interested time
period have not been digitized.
Release of the BBSO film data in digital form is dedicated to Professor
the founder of BBSO, who passed away on 2012 January 3. We thank BBSO
staffs for tremendous efforts in observations and film developing. This
material is based upon work supported by the National Science
Foundation under grant AGS 0849453. Any
opinions, findings, and conclusions or recommendations expressed in
this material are those of the author(s) and do not necessarily reflect
the views of the National Science Foundation.
This project is also supported by NASA