Mishkat al-Masabih 1049
Abu Basra al-Ghifari said:
God’s Messenger led us in the afternoon prayer at al-Mukhammas and said, “This is a prayer which was proposed to your predecessors, but they neglected it. Everyone who keeps observing it will have a double reward, but there is no prayer after it till ash-shahid rises.” Ash-shahid is the star.*

* No particular star is intended. The meaning is that the prayer should be observed when stars become visible. 

Muslim transmitted it.
وَعَن أبي بصرة الْغِفَارِيّ قَالَ: صَلَّى بِنَا رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ بِالْمُخَمَّصِ صَلَاةَ الْعَصْرِ فَقَالَ: «إِنَّ هَذِهِ صَلَاةٌ عُرِضَتْ عَلَى مَنْ كَانَ قَبْلَكُمْ فَضَيَّعُوهَا فَمَنْ حَافَظَ عَلَيْهَا كَانَ لَهُ أَجْرُهُ مَرَّتَيْنِ وَلَا صَلَاةَ بَعْدَهَا حَتَّى يَطْلُعَ الشَّاهِدُ» . وَالشَّاهِد النَّجْم. رَوَاهُ مُسلم