It has been three months since SORCE was launched! SORCE continues
to make excellent daily solar and stellar observations, and the
solar data are received two times each day. The biggest challenge
currently is the task of verifying the four instruments calibrations
and data processing software, so the measurements are truly valid
and ready for the science community.
The calibration process continues on all of the SORCE instruments,
which are currently operating in normal mode. The preliminary
data products generated are meticulously reviewed, and compared
to earlier instrument expectations. The data are also compared
with observations of similar instruments on other spacecrafts
currently operating. After investigating the similarities and
anomalies, scientists work towards data validation by improving
data processing code.
As expected, each instrument is experiencing its own unique set
of anomalies that requires further research. One step at a time,
the instruments and data products are being fine-tuned to maturity,
where the end result will be an accurate set of solar measurements.
Closer Look at the XPS Instrument –
This newsletter explores the preliminary data results from the
XPS (XUV Photometer System) instruments. The XPS measures the
solar soft X-ray (XUV) irradiance from 1 to 34 nm and the bright
hydrogen emission at Lyman-a (121.6 nm). The solar XUV radiation
is emitted from the hot, highly-variable corona on the Sun, and
these high-energy photons are a primary energy source for heating
Earth’s upper atmosphere. The following images and captions
were submitted by Tom Woods, XPS Instrument Scientist.
series of XUV radiation through the onset of solar cycle 23. Images
at the top are obtained in bright helium emission at 30.4 nm by
the SOHO EIT. These images indicate how different the Sun looks
and behaves in the XUV compared to the visible. Sunspots, which
are dark in the visible, are associated with strong magnetic fields
that appear bright in the corona. Data shown here are from different
wavelength bands, but scaled to SNOE 2-7 nm data. THE SORCE XPS
measurements will continue this time series into the declining
phase of the current solar cycle.