Add AstroLoc2 paper (#829)

Updated the main README and localizer README with the new AstroLoc2 paper. Also fixed some broken links to other papers.

Co-authored-by: Brian Coltin <[email protected]>

Author: rsoussan

README.md

@@ -44,10 +44,9 @@ due to NASA legal requirements. Thank you for your understanding.
 
 The ["Astrobee ROS Demo"](https://github.com/Pedro-Roque/astrobee_ros_demo) package provides a C++/Python interface to implement custom control methods in ROS.
 
-For more information, read [Astrobee-related publications](https://www.nasa.gov/content/research-publications-0).
-Learning about the Astrobee [platform](https://www.nasa.gov/sites/default/files/atoms/files/bualat_spaceops_2018_paper.pdf),
-[software](https://www.nasa.gov/sites/default/files/atoms/files/fluckiger2018astrobee.pdf),
-and [localization](https://www.nasa.gov/sites/default/files/atoms/files/coltin2016localization.pdf)
+For more information, read [Astrobee-related publications](https://www.nasa.gov/astrobee-research-publications/).
+Learning about the Astrobee [platform](https://ntrs.nasa.gov/api/citations/20160007769/downloads/20160007769.pdf),
+[software](https://brian.coltin.org/pub/fluckiger2018astrobee.pdf), [original mapping and localization system](https://www.nasa.gov/sites/default/files/atoms/files/coltin2016localization.pdf), and [current localizer](https://ntrs.nasa.gov/api/citations/20250001870/downloads/astroloc2_final.pdf)
 are good starting points.
 
 ### Guest Science

localization/readme.md

@@ -3,11 +3,14 @@
 This folder consists of libraries for the graph-based localizer, sparse mapping pipeline, sensor inputs for localization, and other supporting libraries. 
 
 See the following publications for more details:
+* Ryan Soussan, Marina Moreira, Brian Coltin, and Trey Smith, "AstroLoc2: Fast Sequential Depth-Enhanced Localization for Free-Flying Robots", Int. Conf. on Robotics and Automation (ICRA), 2025. [Link](https://ieeexplore.ieee.org/abstract/document/11128673 "Link") [PDF](https://ntrs.nasa.gov/api/citations/20250001870/downloads/astroloc2_final.pdf "PDF")
+  * Latest publication describing the current sequential graph-based localization system for Astrobee
+
 * Ryan Soussan, Varsha Kumar, Brian Coltin, and Trey Smith, "Astroloc: An efficient and robust localizer for a free-flying robot", Int. Conf. on Robotics and Automation (ICRA), 2022. [Link](https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9811919 "Link")
-  * Latest publication describing the current graph-based localization system for Astrobee
+  * Previous publication describing the former tightly-coupled graph-based localization system for Astrobee
 
 * Brian Coltin, Jesse Fusco, Zack Moratto, Oleg Alexandrov and Robert Nakamura, "Localization from visual landmarks on a free-flying robot," Int. Conf. on Intelligent Robots and Systems (IROS), 2016. [Link](https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7759644 "Link")
-  * Original publication describing previous EKF-based localizer and mapping system for Astrobee
+  * Original publication describing the initial EKF-based localizer and mapping system for Astrobee
 
 If you are using the localizer or mapping pipeline in academic work, please cite the relevant publications above.