astronomy

Is your feature request related to a problem? Please describe.
The Problem with the current implementation is that it seems fixed for the distance to the Moon. We operate Satellites in geostationary orbit and it would be interesting to see the umbra/penumbra based on the distance to those satellites to assess when they enter the shadow during eclipse time (March-April/September-October).

Describe the feature

Previously, Heliopy replaced the FILLVAL defined for a variable in a CDF file with np.nan (cf. https://github.com/heliopython/heliopy/blob/0.15.4/heliopy/data/util.py#L825). Is there a reason why this is not done in SunPy's read_cdf()? (Probably @dstansby)

Proposed solution

Adopt old Heliopy code from https://github.com/heliopython/heliopy/blob/0.15.4/heliopy/

When entering very large and unrealistic values into the Year/Month/Day sliders in the Time Switcher component, the numbers overflow.

We could look into using the diskcache package to cache MAST search operations:

https://pypi.org/project/diskcache/

The package is a disk-based key-value store which makes it easy to specify an expiration time for each entry. This would allow us to e.g. cache search queries for 24 hours, which would significantly speed up searches across different Python processes, whilst largely avoiding