Neutron stars are so dense that a teaspoonful would weigh billions of tons. elaborate
The best time to observe the Moon is during its first quarter or last quarter phases, as the shadows cast by the sun highlight the lunar craters and mountains. elaborate
Telescope observing often involves battling light pollution – even faint starlight can be overwhelmed by city lights, necessitating remote observing locations or special filters. elaborate
Black holes aren't actually "black" in the sense of absorbing all light; they also emit a faint thermal radiation called Hawking radiation. elaborate
A single supernova can briefly outshine an entire galaxy. elaborate