The inmates of Paradise will look to the upper apartment of Paradise as you see the planets in the sky. I narrated this hadith to Nu'man b. Abi 'Ayyash and he said: I heard Abu Sa'id al-Khudri as saying: As you see the shining planets in the eastern and western (sides of) horizon.  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ إِنَّ أَهْلَ الْجَنَّةِ لَيَتَرَاءَوْنَ الْغُرْفَةَ فِي الْجَنَّةِ كَمَا تَرَاءَوْنَ الْكَوْكَبَ فِي السَّمَاءِ قَالَ فَحَدَّثْتُ بِذَلِكَ النُّعْمَانَ بْنَ أَبِي عَيَّاشٍ فَقَالَ سَمِعْتُ أَبَا سَعِيدٍ الْخُدْرِيَّ يَقُولُ كَمَا تَرَاءَوْنَ الْكَوْكَبَ الدُّرِّيَّ فِي الأُفُقِ الشَّرْقِيِّ أَوِ الْغَرْبِيِّ  

This hadith has been narrated on the authority of Abu Hazim through another chain of transmitters.  

عَنْ أَبِي حَازِمٍ بِالإِسْنَادَيْنِ جَمِيعًا نَحْوَ حَدِيثِ يَعْقُوبَ  

The inmates of Paradise would see the inmates of the apartment over them just as you see the shining planets which remain in the eastern and the western horizon because of the superiority some have over others. They said: Messenger of Allah, would in these abodes of Apostles others besides them not be able to reach? He said: Yes, they will, by Him, in Whose hand is my life, those who believe in God and acknowledge the Truth, will reach them.  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ إِنَّ أَهْلَ الْجَنَّةِ لَيَتَرَاءَوْنَ أَهْلَ الْغُرَفِ مِنْ فَوْقِهِمْ كَمَا تَتَرَاءَوْنَ الْكَوْكَبَ الدُّرِّيَّ الْغَابِرَ مِنَ الأُفُقِ مِنَ الْمَشْرِقِ أَوِ الْمَغْرِبِ لِتَفَاضُلِ مَا بَيْنَهُمْ قَالُوا يَا رَسُولَ اللَّهِ تِلْكَ مَنَازِلُ الأَنْبِيَاءِ لاَ يَبْلُغُهَا غَيْرُهُمْ قَالَ بَلَى وَالَّذِي نَفْسِي بِيَدِهِ رِجَالٌ آمَنُوا بِاللَّهِ وَصَدَّقُوا الْمُرْسَلِينَ