Transcript for the First week of November

PAUL
Welcome to Idaho Skies for the first week of November. We’re your hosts, Paul...

RACHEL
...and Rachel.

PAUL
NASA launched the first spacecraft to visit the solar system’s innermost planet forty years ago on the 3rd.

RACHEL
NASA first sent Mariner 10 to Venus so it could use the planet’s gravity to alter its course to approach Mercury. This made Mariner 10 the first spacecraft to use a planet’s gravity to alter its trajectory.

PAUL
During a gravitational assist, a spacecraft steals some of a planet’s kinetic energy or the planet steals some of a spacecraft’s kinetic energy.

RACHEL
The amount of kinetic energy traded between the spacecraft and planet is so tiny that the effects on the planet won’t become obvious for billions of years.

PAUL
However, because of the spacecraft’s tiny mass, the impact can be huge for the spacecraft.

RACHEL
Mariner 10 needed to lose some of its kinetic energy because it had too much to orbit as close to the sun as its destination, Mercury.

PAUL
As Mariner 10 approached Mercury on March 29, 1974, it used Mercury’s gravity to alter its course and pass the planet two additional times.

RACHEL
Gravity wasn’t the only way Mariner 10 altered its orbit.

PAUL
That’s right. The sun’s light is so intense near Mercury that it can push a spacecraft around like a sailboat.

RACHEL
Because of the timing of the spacecraft passages, Mariner 10 was only able to photograph 45% of the planet’s surface.

PAUL
The rest of Mercury remained a mystery until the arrival of the Messenger spacecraft.

RACHEL
Images returned by Mariner 10 and Messenger reveal that Mercury’s surface shares a strong similarity to the moon.

PAUL
Idaho will get a glimpse of Mercury next week.

RACHEL
Before that, you can observe the Taurid meteor shower.

PAUL
The best night is on the 3rd, when the meteor shower reaches its peak intensity.

RACHEL
The moon will be nearly new on the 3rd making it easier to see the fainter members of this shower.

PAUL
You can expect to see around five meteors per hour after it gets dark.

RACHEL
Be sure to watch from a dark location where the effects of house and street lights are minimal.

PAUL
You can tell a meteor is a Taurid if it appears to originate from the east. After 3:00 AM, Taurids will appear to originate from nearly overhead.

RACHEL
Don’t let the fact that astronomers expect to see only five meteors per hour from this shower dissuade you from observing it.

PAUL
That’s because the Taurid meteors appear to contain a larger than usual share of large-sized particles.

RACHEL
You have a greater chance of seeing a fireball or bolide during this shower as a result of the larger meteoroids.

PAUL
The 9th would have been Carl Sagan's 79th birthday.

RACHEL
Most Idahoans know Sagan from his efforts to bring science to the public through his books and the PBS program, Cosmos.

PAUL
Sagan’s gift for science popularization is sorely missed.

RACHEL
Fortunately, we still have people like Neil deGrasse Tyson and Bill Nye.

PAUL
That’s Idaho Skies for the first week of November. Next week, Mercury will be visible to Idahoans early in the morning.

RACHEL
Be sure to follow us on Twitter at Idaho Skies for this week’s event reminders and sky maps.

For Idaho Skies this is Rachel...

PAUL
...and Paul.

RACHEL
Dark skies and bright stars.