This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: Describe qualitatively how the formation of deuterium and its current abundance is related to the ... (Read 58 times)

genevieve1028

  • Hero Member
  • *****
  • Posts: 601
on: Jul 27, 2018
Describe qualitatively how the formation of deuterium and its current abundance is related to the critical density of the universe.
 
  What will be an ideal response?

Question 2

What do the orbits of Populations I and II stars tell us about the formation of the Milky Way?
 
  What will be an ideal response?


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

adf223

  • Sr. Member
  • ****
  • Posts: 304
Reply #1 on: Jul 27, 2018
Answer to Question 1

Since stars tend to destroy deuterium, it is assumed that all existing deuterium is primordial. Also, the higher the density of the universe, the more matter is around for the deuterium to react with, so high density means small quantities of deuterium and vice versa. This allows an independent measure of the density of the universe, and reveals that the hadronic (protons and neutrons) mass of the universe is only about 3 of the critical density.

Answer to Question 2

Older Population II stars move in comet-like orbits, well above the plane of the Galaxy in the spherical Halo. The Population I stars formed later, after most of the remaining gas and dust had settled down into a disk, flattened by the rotation of the condensing Galaxy. Their orbits are much more like those of planets, fairly circular and in the galactic plane.


genevieve1028

  • Member
  • Posts: 601
Reply 2 on: Jul 27, 2018
Great answer, keep it coming :)

duy1981999

  • Member
  • Posts: 341
Reply 3 on: Yesterday
YES! Correct, THANKS for helping me on my review

« previous next »
 

Did you know?

Vampire bats have a natural anticoagulant in their saliva that permits continuous bleeding after they painlessly open a wound with their incisors. This capillary blood does not cause any significant blood loss to their victims.

Did you know?

Although not all of the following muscle groups are commonly used, intramuscular injections may be given into the abdominals, biceps, calves, deltoids, gluteals, laterals, pectorals, quadriceps, trapezoids, and triceps.

Did you know?

Patients who cannot swallow may receive nutrition via a parenteral route—usually, a catheter is inserted through the chest into a large vein going into the heart.

Did you know?

Approximately one in three babies in the United States is now delivered by cesarean section. The number of cesarean sections in the United States has risen 46% since 1996.

Did you know?

Patients who have been on total parenteral nutrition for more than a few days may need to have foods gradually reintroduced to give the digestive tract time to start working again.

Some red squirrels adopt the offspring of related individuals, a likely example of kin selection pro Some red squirrels adopt the offspring of related individuals, a likely example of kin selection pro
Procedures for Diagnostic Tests Related to the Musculoskeletal system Procedures for Diagnostic Tests Related to the Musculoskeletal system
Formation of Dilute Urine Formation of Dilute Urine
A multistep model for colon cancer. The first mutation, in the APC gene, leads to the formation of p A multistep model for colon cancer. The first mutation, in the APC gene, leads to the formation of p
Describe the Conceptual Forecasting Framework in your own words. Describe the Conceptual Forecasting Framework in your own words.
Gastrulation and the onset of organ formation. Gastrulation and the onset of organ formation.
Video: Factors that influence muscle tension - Sarcomere length and force, understretched and overstretched

For a complete list of videos, visit our video library