Introduction¶
Documentation Motivation¶
The main goal of this documentation is to make both the code used to create the LIFE Target Database as well as the database itself follow the FAIR principles https://www.nature.com/articles/sdata201618. Their goal is that data are Findable, Accessible, Interoperable and Reusable (FAIR) for machines. The same principle can be translated to research software. FAIR has become a global norm for good data and software stewardship and a prerequisite for reproducibility.
Database Motivation¶
Broader context - The LIFE initiative¶
This project is part of the larger LIFE initiative standing for Large Interferometer For Exoplanets. A brief overview is given here: LIFE was initiated in 2017 and officially kicked-off in 2018 with the goal to develop the science, the technology and a roadmap for an ambitious space mission that will allow humankind to detect and characterize the atmospheres of hundreds of nearby extrasolar planets including dozens that are similar to Earth. Thanks to NASA’s Kepler and TESS missions and dedicated, long-term exoplanet searches from the ground, we know that small, rocky exoplanets are ubiquitous in the Milky Way and also in the immediate Solar neighbourhood. Detecting the nearest exoplanets, scrutinizing their atmospheres and searching for habitable conditions and indications of biological activity is a cornerstone of 21st century astrophysics.
LIFE Target Database¶
The Target Database for LIFE and ancillary observations is a repository for relevant data about potential stellar target systems. Our primary objectives include offering easy database access and extracting input target catalogs to predict exoplanet detection yields. Simultaneously, we aim to determine important missing observations, offer data to derive mission design decisions, and provide context for the analysis of data obtained by LIFE. We presented the database in our Research Note “Database of Candidate Targets for the LIFE Mission” (NASA/ADS).
LIFE samples¶
In order to prevent confusion between terminology used by other missions here a short overview of the different LIFE samples.
Sampel |
Goal |
Assumption |
Object Types |
# |
|---|---|---|---|---|
Target Database |
As much data as possible on potential targets |
30pc, no single brown or white dwarfs |
Stars, Systems, Planets, Disks |
~10⁴ |
Star-Cat |
As much data as needed for LIFEsim |
mature single stars + wide binaries (stable planet orbit in hz) |
Stars |
~10³ |
LIFEsim output sample |
Show for which mission parameters e.g. S/N what stellar objects (e.g. amount, to what distance) would be retrieved |
highest simulated observation yield |
Stars |
~10² |
Golden Targets |
targets that allow detailed characterization in relatively short observation times for oportunity of potential “time-resolved” experiments e.g. seasonal changes |
best a priori known candidates e.g. proxima, Teegarden’s star/planets, stars also observed with HWO |
Stars |
~10¹ |
Final Targets |
best stars for LIFE mission |
golden targets + some of LIFEsim output sample |
Stars |
~10² |
The target database contains as much data as possible on potential targets. It consists of stars (no single brown or white dwarfs), systems, planets and disks within 30 pc of the Sun and contains of order 10⁴ objects. The Star-Cat (also sometimes called input target catalog) is extracted from the database and contains as much data as needed for LIFEsim. It consists of main-sequence single stars and wide binaries (with stable planet orbits in the habitable zone) and contains of order 10³ stars. LIFEsim shows for which mission parameters (e.g. S/N) what stellar objects (e.g. amount, to what distance) would be retrieved. This output sample consists of ~10² stars with the highest simulated observation yield. For targets that allow detailed characterization in relatively short observation times for oportunity of potential “time-resolved” experiments e.g. seasonal changes we have the golden targets sample. It consists of ~10¹ of best a priori known stars (e.g. Proxima, stars also observed with HWO). The sample of the final targets are the ~10² best stars for the LIFE mission. They consist of the golden targets together with some of the LIFEsim output sample.