Concept explainers
How are distant (young) galaxies different from the galaxies that we see in the universe today?
To explain:
The difference between distant young galaxies and the galaxies that are seen in the universe today.
Explanation of Solution
Introduction:
Distant young galaxies are different from present day galaxies in terms of star formation, composition and shape. Distant galaxies were present at the time when the universe was only 500 million years old while present day galaxy is about 13.8 years old.
Distant galaxies were small as compared to present day galaxy and rate of star formation was very high in young galaxies and they were numerous, less luminous and rich in gas.
Distant galaxies were small and elliptical as at that time, spiral arms, bulges and disks were not there.They contain mostly old stars and they were irregular and smaller than present day galaxies. Present day galaxies are spiral in shape and they contain young stars with interstellar matter.
Formation of larger galaxies is the result of combination of fragment of old galaxies. The color of galaxy indicates the age of star by which it is populated.Blue galaxies contain hot stars and star formation occurs at high rate.
Conclusion:
Thus,Distant galaxies were small as compared to present day galaxy and rate of star formation was very high in young galaxies and they were numerous, less luminous and gas rich.
Want to see more full solutions like this?
Chapter 28 Solutions
Astronomy
Additional Science Textbook Solutions
Biology: Life on Earth (11th Edition)
Applications and Investigations in Earth Science (9th Edition)
Chemistry: An Introduction to General, Organic, and Biological Chemistry (13th Edition)
Microbiology: An Introduction
College Physics: A Strategic Approach (3rd Edition)
Human Biology: Concepts and Current Issues (8th Edition)
- Lab-Based Section Use the following information to answer the lab based scenario. A student performed an experiment in an attempt to determine the index of refraction of glass. The student used a laser and a protractor to measure a variety of angles of incidence and refraction through a semi-circular glass prism. The design of the experiment and the student's results are shown below. Angle of Incidence (°) Angle of Refraction (º) 20 11 30 19 40 26 50 31 60 36 70 38 2a) By hand (i.e., without using computer software), create a linear graph on graph paper using the student's data. Note: You will have to manipulate the data in order to achieve a linear function. 2b) Graphically determine the index of refraction of the semi-circular glass prism, rounding your answer to the nearest hundredth.arrow_forwardUse the following information to answer the next two questions. A laser is directed at a prism made of zircon (n = 1.92) at an incident angle of 35.0°, as shown in the diagram. 3a) Determine the critical angle of zircon. 35.0° 70° 55 55° 3b) Determine the angle of refraction when the laser beam leaves the prism.arrow_forwardUse the following information to answer the next two questions. A laser is directed at a prism made of zircon (n = 1.92) at an incident angle of 35.0°, as shown in the diagram. 3a) Determine the critical angle of zircon. 35.0° 70° 55 55° 3b) Determine the angle of refraction when the laser beam leaves the prism.arrow_forward
- No chatgpt pls will upvotearrow_forwardA beam of alpha-particles of energy 7.3MeV is used.The protons emitted at an angle of zero degree are found to have energy of 9.34MeV.Find the Q-value of this reaction .arrow_forwardAn aluminum rod and a copper rod have the same length of 100cm at 5C. At what temperatures would one of the rods be 0.5 mm longer than the other? Which rod is longer at such temperature?arrow_forward
- ROTATIONAL DYNAMICS Question 01 A solid circular cylinder and a solid spherical ball of the same mass and radius are rolling together down the same inclined. Calculate the ratio of their kinetic energy. Assume pure rolling motion Question 02 A sphere and cylinder of the same mass and radius start from ret at the same point and more down the same plane inclined at 30° to the horizontal Which body gets the bottom first and what is its acceleration b) What angle of inclination of the plane is needed to give the slower body the same acceleration Question 03 i) Define the angular velocity of a rotating body and give its SI unit A car wheel has its angular velocity changing from 2rads to 30 rads seconds. If the radius of the wheel is 400mm. calculate ii) The angular acceleration iii) The tangential linear acceleration of a point on the rim of the wheel Question 04 in 20arrow_forwardQuestion B3 Consider the following FLRW spacetime: t2 ds² = -dt² + (dx² + dy²+ dz²), t2 where t is a constant. a) State whether this universe is spatially open, closed or flat. [2 marks] b) Determine the Hubble factor H(t), and represent it in a (roughly drawn) plot as a function of time t, starting at t = 0. [3 marks] c) Taking galaxy A to be located at (x, y, z) = (0,0,0), determine the proper distance to galaxy B located at (x, y, z) = (L, 0, 0). Determine the recessional velocity of galaxy B with respect to galaxy A. d) The Friedmann equations are 2 k 8πG а 4πG + a² (p+3p). 3 a 3 [5 marks] Use these equations to determine the energy density p(t) and the pressure p(t) for the FLRW spacetime specified at the top of the page. [5 marks] e) Given the result of question B3.d, state whether the FLRW universe in question is (i) radiation-dominated, (ii) matter-dominated, (iii) cosmological-constant-dominated, or (iv) none of the previous. Justify your answer. f) [5 marks] A conformally…arrow_forwardSECTION B Answer ONLY TWO questions in Section B [Expect to use one single-sided A4 page for each Section-B sub question.] Question B1 Consider the line element where w is a constant. ds²=-dt²+e2wt dx², a) Determine the components of the metric and of the inverse metric. [2 marks] b) Determine the Christoffel symbols. [See the Appendix of this document.] [10 marks] c) Write down the geodesic equations. [5 marks] d) Show that e2wt it is a constant of geodesic motion. [4 marks] e) Solve the geodesic equations for null geodesics. [4 marks]arrow_forward
- Page 2 SECTION A Answer ALL questions in Section A [Expect to use one single-sided A4 page for each Section-A sub question.] Question A1 SPA6308 (2024) Consider Minkowski spacetime in Cartesian coordinates th = (t, x, y, z), such that ds² = dt² + dx² + dy² + dz². (a) Consider the vector with components V" = (1,-1,0,0). Determine V and V. V. (b) Consider now the coordinate system x' (u, v, y, z) such that u =t-x, v=t+x. [2 marks] Write down the line element, the metric, the Christoffel symbols and the Riemann curvature tensor in the new coordinates. [See the Appendix of this document.] [5 marks] (c) Determine V", that is, write the object in question A1.a in the coordinate system x'. Verify explicitly that V. V is invariant under the coordinate transformation. Question A2 [5 marks] Suppose that A, is a covector field, and consider the object Fv=AAμ. (a) Show explicitly that F is a tensor, that is, show that it transforms appropriately under a coordinate transformation. [5 marks] (b)…arrow_forwardHow does boiling point of water decreases as the altitude increases?arrow_forwardNo chatgpt pls will upvotearrow_forward
- AstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStaxStars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage LearningFoundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
- Stars and GalaxiesPhysicsISBN:9781305120785Author:Michael A. Seeds, Dana BackmanPublisher:Cengage LearningPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning