Available Data¶

rocks provides easy access to the asteroid data stored on SsODNet. There are two main data repositories, the ssoCard and the datacloud.

ssoCard and datacloud¶

Every known asteroid has an ssoCard and every ssoCard only refers to a single asteroid. It stores the best single value for each parameter of the asteroid, e.g. by computing weighted averages of the best available data.

The datacloud is the collection of (almost) all published data on asteroids. It is split into catalogues, e.g. the diamalbedo catalogue containing observations of asteroid diameters and albedos. rocks allows to query these catalogues for one asteroid at a time, returning all entries belonging to that asteroid in the requested catalogue.

When querying for asteroid parameters, specifying the parameter name as singular or plural will retrieve its value from the ssoCard in the former and from the datacloud in the latter case, as shown below. See the list of available parameters here.

Command Line

$ rocks taxonomy Eos
K

$ rocks taxonomies Eos
+-----------+---------+--------+-----------+------------------+------+--------+
| scheme    | complex | method | waverange | shortbib         | year | class_ |
+-----------+---------+--------+-----------+------------------+------+--------+
| Tholen    | S       | Phot   | VIS       | Tholen+1989      | 1989 | S      |
| Bus       | K       | Spec   | VIS       | Bus&Binzel+2002  | 2002 | K      |
| Bus       | K       | Spec   | VIS       | MotheDiniz+2005  | 2005 | K      |
| Bus       | K       | Spec   | VISNIR    | MotheDiniz+2008a | 2008 | K      |
| Bus-DeMeo | K       | Spec   | VISNIR    | Clark+2009       | 2009 | K      |
| Bus-DeMeo | K       | Spec   | VISNIR    | DeMeo+2009       | 2009 | K      |
+-----------+---------+--------+-----------+------------------+------+--------+

python

>>> from rocks import Rock
>>> ceres = Rock(1, datacloud='taxonomies')
>>> ceres.taxonomy.class_    # ssoCard
'C'
>>> ceres.taxonomies.class_  # datacloud
['G', 'C', 'C', 'C', 'C', 'G', 'C']

ssoCards and datacloud catalogues are cached on your computer for quicker data access, as further outlined below.

Data stored on your machine¶

rocks retrieves all requested asteroid data from SsODNet and stores it in a cache directory to increase following data look-ups. The cache is located at ~/.cache/rocks. It is created if it does not exist when rocks is invoked.

To reduce the time of resolving the identity of asteroids identifiers, rocks keeps a local index of asteroid names and numbers in the cache directory. This index is retrieved from SsODNet if it does not exist when rocks is invoked.

The data in the cache directory can be updated or removed using the status command. It should be run regularly (e.g. once a month) to ensure that the data is up-to-date:

$ rocks status

Contents of /home/mmahlke/.cache/rocks:

        41 ssoCards
        15 datacloud catalogues

        Asteroid name-number index updated on 12 Jul 2022

Update or clear the cached ssoCards and datacloud catalogues?
[0] Do nothing [1] Clear the cache [2] Update the data (1): 1

Clearing the cached ssoCards and datacloud catalogues..

Update the asteroid name-number index?
[0] No [1] Yes (1): 1

Building index |---------------------------| 100%

The command accepts two flags to skip the interactive prompts: the --clear or -c flag deletes the cached asteroid data but leaves the index in place. The --update or -u flag updates the cached asteroid data and updates the asteroid name-number index.