However, because the planets sit so low in the sky during sunrise tomorrow, they may be hard to spot, especially for northern observers. So, get out a little early to ensure you can track down Venus before the Sun's glare washes it away.Though it's especially tough to identify Mercury, it helps to start by locating Venus, then use binoculars to help track down the innermost planet.Mercury currently shines at magnitude 0.9, while dim Neptune shines at magnitude 8.0. Though it's technically possible to spot Neptune from an extremely dark-sky site, the fact that the planet hangs so near the horizon during twilight makes it a daunting challenge.When viewed through a telescope this week, Venus shows a disk that appears 13" across and about 80 percent lit. The disk of Mercury, on the other hand, spans 9.2" and is about 30 percent lit. Finally, though the disk of Neptune is 100 percent lit, it spans just 2.2".For more quick and easy observing tips, check out The sky this week for March 29 to April 7