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Why is throwing trash into the Sun harder than pointing a rocket at it?

A rocket leaves Earth already carrying Earth’s motion around the Sun. Pointing inward does not erase that sideways velocity, so reaching the Sun is a problem of changing an orbit as well as choosing a direction.

5–7 min

Questions you could explore

  • How can a spacecraft move closer to the Sun while becoming faster overall?

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Space

Why does the Moon change shape during a month?

A crescent Moon is not a partly switched-off Moon. Sunlight still illuminates half of it, while its changing position around Earth changes how much of that lit half we can see.

3–5 min

Why does the Moon change shape during a month?

Space3–5 minA crescent Moon is not a partly switched-off Moon. Sunlight still illuminates half of it, while its changing position around Earth changes how much of that lit half we can see.

Space

Two eclipses, two different shadows

A solar eclipse and a lunar eclipse both involve the Sun, Earth, and Moon, but the shadow falls in a different place. In one, the Moon’s shadow reaches Earth; in the other, the Moon moves into Earth’s shadow. The Moon’s tilted orbit helps explain why these alignments do not happen every month.

5–7 min

Two eclipses, two different shadows

Space5–7 minA solar eclipse and a lunar eclipse both involve the Sun, Earth, and Moon, but the shadow falls in a different place. In one, the Moon’s shadow reaches Earth; in the other, the Moon moves into Earth’s shadow. The Moon’s tilted orbit helps explain why these alignments do not happen every month.

Space

What can a century-old photograph tell us about a changing sky?

An old astronomical glass plate preserves an observation that cannot be made again today. Harvard’s plate archive brings such records into digital comparison, alongside dates, logbooks, and calibration work. The glass image alone is not the whole dataset; knowing how and when it was made changes what can be inferred from it.

8–10 min

What can a century-old photograph tell us about a changing sky?

Space8–10 minAn old astronomical glass plate preserves an observation that cannot be made again today. Harvard’s plate archive brings such records into digital comparison, alongside dates, logbooks, and calibration work. The glass image alone is not the whole dataset; knowing how and when it was made changes what can be inferred from it.

Why is throwing trash into the Sun harder than pointing a rocket at it? | Speech Topic | speaking.app