Space Test

A light year is a unit appropriate for measuring which of the following characteristics of celestial bodies?

• Size of galaxies

• Mass of stars

• Time of planetary orbits

• Temperature of nebula

  
  

Answer explanation

A light year measures distance, making it suitable for expressing the size of galaxies. It is not used for mass, time, or temperature, which require different units.

Tags

NGSS.MS-ESS1-3

Looking at the diagram shown, when white dwarf stars are compared to giant stars, white dwarfs have ___.

1.      Higher luminosity/brightness

2.      Lower luminosity/brightness

3.      Cooler temperatures

4.      Higher temperatures

• 1 & 3 only

• 1 & 4 only

• 2 & 3 only

• 2 & 4 only

Answer explanation

White dwarfs have lower luminosity compared to giant stars due to their smaller size, but they can have higher temperatures. Thus, the correct choice is 2 & 4 only.

All observable objects outside our galaxy, when viewed from Earth, have their spectra shifted to slightly longer wavelengths.  This is sometimes called red-shift.  Astronomers have concluded that this is evidence that all objects in the universe are –

• Hotter than the sun.

• Moving away from each other.

• Older than our solar system.

• Absorbing radiation from the stars.

Answer explanation

The red-shift indicates that light from distant galaxies is stretched to longer wavelengths, suggesting they are moving away from us. This supports the conclusion that all objects in the universe are moving away from each other.

Tags

NGSS.HS-ESS1-2

Which statement correctly identifies the relationship between wavelength and energy?

• X-rays have smaller wavelengths and lower energy than ultraviolet waves.

• Visible light has longer wavelengths and higher energy than infrared waves.

• Radio waves have longer wavelengths and higher energy than gamma rays.

• Visible light has shorter wavelengths and higher energy than radio waves.

Answer explanation

The correct statement is that visible light has shorter wavelengths and higher energy than radio waves. This is consistent with the electromagnetic spectrum, where energy increases as wavelength decreases.

Tags

NGSS.MS-PS4-1

What force is responsible for these orbiting motions?

• A.      Electricity

• B.      Friction

• C.      Gravity

• D.     Magnetism

Answer explanation

The force responsible for orbiting motions is gravity. It attracts objects towards each other, keeping planets, moons, and satellites in their orbits. Electricity, friction, and magnetism do not govern these celestial movements.

Tags

NGSS.MS-ESS1-1

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

The most common element in a star, such as the Sun, is

• A.      Oxygen

• B.      Carbon

• C.      Hydrogen

• D.     Helium

Answer explanation

The most common element in stars, including the Sun, is hydrogen. It makes up about 74% of the Sun's mass, while helium is the second most abundant element. Oxygen and carbon are present in much smaller amounts.

Tags

NGSS.MS-PS1-1

Proxima Centauri is a star that is 4.2 light years from Earth.  Based solely on this information, which of the following conclusions can be drawn?

• The diameter of this star is more than four times larger than the Sun.

• Light we see from the star took more than four years to reach Earth.

• This star takes a little more than four years to make one rotation.

• The gravity of this star would make an object weigh four times more than on Earth.

Answer explanation

The correct conclusion is that light from Proxima Centauri takes over four years to reach Earth, as it is 4.2 light years away. The other statements about size, rotation, and gravity cannot be inferred from the distance alone.

Which of these sequences the stars from least to greatest in absolute magnitude or luminosity?

• A.      Sirius B, Spica, Capella, Deneb

• B.      Capella, Deneb, Sirius B, Spica

• C.      Capella, Sirius B, Deneb, Spica

• D.     Sirius B, Capella, Spica, Deneb

Answer explanation

The correct order of absolute magnitude from least to greatest is Sirius B (the faintest), followed by Capella, then Spica, and finally Deneb (the brightest). Thus, the correct choice is D: Sirius B, Capella, Spica, Deneb.

Tags

NGSS.HS-ESS1-3

A celestial body moving in an elliptical orbit around a star is called a what?

• Alien

• Moon

• Star

• Planet

Answer explanation

A celestial body that orbits a star in an elliptical path is defined as a planet. Unlike moons or stars, planets are the primary bodies that revolve around stars, making 'Planet' the correct answer.

Tags

NGSS.MS-ESS1-2

The Earth revolves around its _____ once very 24 hours.

• Tilt

• Axis

• Side

• Revolution

Answer explanation

The Earth revolves around its axis, which is an imaginary line that runs from the North to the South Pole. This rotation occurs approximately every 24 hours, resulting in day and night.

Tags

NGSS.MS-ESS2-6