Salat al-Maghrib (Sunset)

The Sunset Contact Prayer (Salat al-Maghrib) can be found in the verse.

[11:114] You shall observe the Contact Prayers (Salat) at both ends of the day, and during the night. The righteous works wipe out the evil works. This is a reminder for those who would take heed.

وَأَقِمِ ٱلصَّلَوٰةَ طَرَفَىِ ٱلنَّهَارِ وَزُلَفًا مِّنَ ٱلَّيْلِ إِنَّ ٱلْحَسَنَـٰتِ يُذْهِبْنَ ٱلسَّيِّـَٔاتِ ذَٰلِكَ ذِكْرَىٰ لِلذَّٰكِرِينَ

The expression "wazulafan mina al-layli" ( وَزُلَفًا مِّنَ ٱلَّيْلِ ) means the first part of the night.

1	wa-aqimi	وَأَقِمِ	And observe
2	l-ṣalata	ٱلصَّلَوٰةَ	the Contact Prayer (Salat)
3	ṭarafayi	طَرَفَىِ	(at the) two ends (of)
4	l-nahāri	ٱلنَّهَارِ	the day
5	wazulafan	وَزُلَفًا	and (at) the approach / first part [of the night]
6	mina	مِّنَ	of
7	al-layli	ٱلَّيْلِ	the night.

Since night (layl) starts at sunset, this timeframe corresponds from sunset to when the sun is 18 degrees below the horizon and when east and west become indistinguishable in the night sky.