PSCI 1421 – Measuring the Velocity of a
Coronal Mass Ejection – Lab 10 questions
with answers
Introduction
This document contains 64 practice questions with precise answers
covering coronal mass ejections (CMEs), including their formation,
velocity, propagation, magnetic fields, and effects on Earth. It also
covers coronagraphs, LASCO, SOHO, SDO, solar wind interactions,
space weather forecasting, geomagnetic storms, satellite impacts,
and CME research methods.
Exam Questions and Answers
1: What is a Coronal Mass Ejection (CME)?--- correct precise answer
---
A Coronal Mass Ejection (CME) is a significant release of plasma
and magnetic field from the solar corona, which can cause
geomagnetic storms when it interacts with Earths magnetosphere.
2: Why is it important to measure the velocity of a CME?--- correct
precise answer ---
Measuring the velocity of a CME is important because it helps
predict the arrival time of the CME at Earth, which is crucial for
preparing for potential geomagnetic storms that can affect
satellites, power grids, and communication systems.
,3: What instruments are typically used to observe CMEs?--- correct
precise answer --- Instruments such as coronagraphs on spacecraft
like the Solar and
Heliospheric Observatory (SOHO) and the Solar Dynamics
Observatory (SDO) are typically used to observe CMEs.
4: How does a coronagraph work?--- correct precise answer ---
A coronagraph works by blocking the bright light from the Suns
surface, allowing the faint light from the corona and CMEs to be
observed.
5: What is the difference between a solar flare and a CME?---
correct precise answer ---
A solar flare is a sudden flash of increased brightness on the Sun,
usually observed near its surface, while a CME involves the ejection
of a large amount of plasma and magnetic field from the corona.
6: How can the velocity of a CME be calculated?--- correct precise
answer ---
The velocity of a CME can be calculated by measuring the distance
it travels over a certain period, using images from instruments like
coronagraphs and applying the formula: velocity = distance/time.
7: What role does the LASCO instrument play in observing CMEs?---
correct precise answer ---
, The Large Angle and Spectrometric Coronagraph (LASCO) on the
SOHO spacecraft plays a crucial role in observing CMEs by
providing images that show the CMEs progress and structure.
8: What are the typical velocities of CMEs?--- correct precise answer
---
CMEs typically have velocities ranging from 250 km/s to over 3000
km/s.
9: How does the density of the solar corona affect CME
propagation?--- correct precise answer ---
The density of the solar corona affects CME propagation by
influencing the drag force on the CME, which can alter its speed
and trajectory.
10: What is the significance of the CMEs magnetic field
orientation?--- correct precise answer ---
The orientation of a CMEs magnetic field is significant because it
determines how the CME will interact with Earths magnetosphere,
potentially causing geomagnetic storms if the magnetic fields are
aligned oppositely.
11: How can the time of arrival of a CME at Earth be predicted?---
correct precise answer ---
The time of arrival of a CME at Earth can be predicted by
calculating its velocity and trajectory, using models that simulate
its path through the solar system.
Coronal Mass Ejection – Lab 10 questions
with answers
Introduction
This document contains 64 practice questions with precise answers
covering coronal mass ejections (CMEs), including their formation,
velocity, propagation, magnetic fields, and effects on Earth. It also
covers coronagraphs, LASCO, SOHO, SDO, solar wind interactions,
space weather forecasting, geomagnetic storms, satellite impacts,
and CME research methods.
Exam Questions and Answers
1: What is a Coronal Mass Ejection (CME)?--- correct precise answer
---
A Coronal Mass Ejection (CME) is a significant release of plasma
and magnetic field from the solar corona, which can cause
geomagnetic storms when it interacts with Earths magnetosphere.
2: Why is it important to measure the velocity of a CME?--- correct
precise answer ---
Measuring the velocity of a CME is important because it helps
predict the arrival time of the CME at Earth, which is crucial for
preparing for potential geomagnetic storms that can affect
satellites, power grids, and communication systems.
,3: What instruments are typically used to observe CMEs?--- correct
precise answer --- Instruments such as coronagraphs on spacecraft
like the Solar and
Heliospheric Observatory (SOHO) and the Solar Dynamics
Observatory (SDO) are typically used to observe CMEs.
4: How does a coronagraph work?--- correct precise answer ---
A coronagraph works by blocking the bright light from the Suns
surface, allowing the faint light from the corona and CMEs to be
observed.
5: What is the difference between a solar flare and a CME?---
correct precise answer ---
A solar flare is a sudden flash of increased brightness on the Sun,
usually observed near its surface, while a CME involves the ejection
of a large amount of plasma and magnetic field from the corona.
6: How can the velocity of a CME be calculated?--- correct precise
answer ---
The velocity of a CME can be calculated by measuring the distance
it travels over a certain period, using images from instruments like
coronagraphs and applying the formula: velocity = distance/time.
7: What role does the LASCO instrument play in observing CMEs?---
correct precise answer ---
, The Large Angle and Spectrometric Coronagraph (LASCO) on the
SOHO spacecraft plays a crucial role in observing CMEs by
providing images that show the CMEs progress and structure.
8: What are the typical velocities of CMEs?--- correct precise answer
---
CMEs typically have velocities ranging from 250 km/s to over 3000
km/s.
9: How does the density of the solar corona affect CME
propagation?--- correct precise answer ---
The density of the solar corona affects CME propagation by
influencing the drag force on the CME, which can alter its speed
and trajectory.
10: What is the significance of the CMEs magnetic field
orientation?--- correct precise answer ---
The orientation of a CMEs magnetic field is significant because it
determines how the CME will interact with Earths magnetosphere,
potentially causing geomagnetic storms if the magnetic fields are
aligned oppositely.
11: How can the time of arrival of a CME at Earth be predicted?---
correct precise answer ---
The time of arrival of a CME at Earth can be predicted by
calculating its velocity and trajectory, using models that simulate
its path through the solar system.
