Astronomy (from Greek: ἀστρονομία, literally meaning the science that studies the laws of the stars) is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates outside Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole.Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Babylonians, Greeks, Indians, Egyptians, Chinese, Maya, and many ancient indigenous peoples of the Americas. In the past, astronomy included disciplines as diverse as astrometry, celestial navigation, observational astronomy, and the making of calendars. Nowadays, professional astronomy is often said to be the same as astrophysics.Professional astronomy is split into observational and theoretical branches. Observational astronomy is focused on acquiring data from observations of astronomical objects. This data is then analyzed using basic principles of physics. Theoretical astronomy is oriented toward the development of computer or analytical models to describe astronomical objects and phenomena. These two fields complement each other. Theoretical astronomy seeks to explain observational results and observations are used to confirm theoretical results.
Astronomy is one of the few sciences in which amateurs play an active role. This is especially true for the discovery and observation of transient events. Amateur astronomers have helped with many important discoveries, such as finding new comets.
Homework Statement
(a) Calculate sidereal time at 11am on December 8th of any year.
(b) Calculate the Greenwich Sidereal Time when the local sidereal time on longitude 20 degrees (West) is 20h 45m.
Homework Equations
I know from my notes that a Sidereal day is 4 minutes shorter than...
Hey there guys!
I haven't been on this forum a while, been busy with school work and assessments, but still catching up on astronomical developments and physical advancements (Higgs Boson around the corner soon?!)
Anyways, as the title suggests, I'm definitely entering a local science fair...
My main interest in physics is b/c of astronomy. I'm doing physics undergrad as a stepping stone to grad school astronomy/astrophysics. However upon introspection I notice that my main interest in space lies in the solar system and exoplanets and the potential for life. Is astronomy then the...
Homework Statement
A telescope has a focal ratio of f/7.5. You wish to use it with a spectrometer that requires an f/10 beam at its input. Compute the focal length of a 50mm diameter lens that, when inserted in the beam 150mm in front of the unmodified focal plane, produces the required beam...
The most efficient way to reach Mars from Earth is following the Hohmann Transfer Orbit
(Wolfgang Hohmann, 1925). A spaceship must first get free of Earth (it still orbits the Sun
together with Earth, at 30 km/s, at a distance of 1 AU), then it adds speed so that its aphelion
(in its orbit...
Hi guys,
I am wondering whether I would be taken seriously by the admissions committees if I were to apply for a B.S. degree in Physics-Astronomy (concentration) because I am in the social sciences, getting my M.A. in a social science field this May. I want to earn my Ph.D. in Astronomy...
I'm currently a second-year student in EE at a large state school (top 30, I think). I chose EE when I applied, but I never really put any thought towards what major I wanted. I had taken AP physics, etc in high school and was always pretty good in math and sciences, so people told me to go...
Hello, i am deciding between a career in astronomy or astrophysics and need help.
I wish to know the differences in the two careers. What do each study? what is the pay difference in Canada? Where do each work and what do they work on?
Please tell me if there are mistakes, however small, in the answers I have provided to these questions. Thank you in advance.
1. Why are pulsars not always associated with supernova remnants?
Most pulsars are created by Type II supernovae, but out of all the pulsars detected yet (around...
I'd like to make a thread for those who are applying to REU programs in physics and the like this summer.
Please post where you have applied, what your research interests are, and post when you hear from specific programs to help others make their decisions.
Also feel free to discuss any...
Hi All! My name is bergw, I'm new here and I'm looking for some advice.
I'm a software engineer in the CAD business who is dying for more interesting work! I'd really like to get back to the interests I had back from college(Astronomy) but I'm finding it difficult even finding software...
1. Photons approaching a black hole will initially
a. all of the above are possible depending on distance from the event horizon
b. pass by with their direction changing (bending/curving)
c. fall into the black hole
d. go into orbit around the black hole
e. pass by without...
most good observing locations seem to be located in high-altitude, COLD, places. even though i am not at high altitude, it is still mighty cold at night here in oregon.
what would you recommend for an affordable method to do basic observation where the scope is located outdoors but viewable...
I am interested in the Astronomy and Astrophysics program at the University of Toronto. How well does one need to do in high-school to get into the program? What are the required courses and what marks would be advantageous?
Any help would be greatly appreciated.
I'm a freshman in university, just finishing up my first semester (I've got 3 finals left and then I'm done). I just turned 18 last week, too. I'm in arts at the moment, but I've been thinking that I want to switch to sciences and aim for a degree in astronomy...the problems I face, however:
-...
As part of my junior curriculum I'm taking a college prep course. As part of this course I am gathering a list of colleges I plan on applying to, including several safety schools. I have several schools that I am totally confident that I will be able to get in, but I wouldn't quite call them...
Sooo I wasn't sure if I should put this here or in the astrophysics section, but I figured electrical engineering was more relevant for my question.
I'm involved in a project at my university to build a (very) simple radio telescope, but I'm having a bit of trouble with the radiometer...
Hey everyone! I am new to the forum so be kind. I tried using the search function to find an answer to this question but could not dig one up. I have come to a point in my life where I need a career change I am 26 and considering a few options to shake up my life. I have long had a passion for...
Hello all,
I'm a surveyor working on an Excel spreadsheet to convert FK5 positions into altitude and azimuth system. Yeah, I know there's an FK6, but one step at a time.
I know it sounds simple, right.
But I have to account for proper motion, precession, nutation, aberration, parallax...
Hi All,
Just some quick background that may be relevant before my question: I am 29 years old and am back in school after not knowing what I wanted to after high school. Originally, I did well some terms and not so well other terms starting out, and I ended up taking a ~5year break. In my...
PhD Astronomy Prof: "Paucity of evidence for the Big Bang"
an acquaintance of mine who holds a PhD in physics and teaches astronomy at a university says the is "a paucity of evidence for Big Bang theorizing". After I close my gaping mouth how should I respond?
:biggrin: I need a telescope for my astronomy class next semester :biggrin::biggrin::biggrin: and a $700 budget...having a difficult time deciding which one to get :-/
Hey I'm 21 years old, I have been going to a community college for about a year and a half.. ofcourse this college is not difficult and I have close to a 4.0..
Basically I've always have been fascinated with outer space, I'm wondering if anyone here can guide me on the degrees I would need to...
Homework Statement
"Determine a surface temperature value for the Sun from the angular diameter of the Sun and the solar constant."
Homework Equations
L=4π(R^2)σT^4
The Attempt at a Solution
At this point my only stumbling block is I don't understand the relationship between the solar...
Homework Statement
I am not sure what to do with Maple. I've barely used it at all, but trying to figure out why this won't work with what I have below.
Plot schematically the change in equilibrium temperature of Earth, if its albedo changes from 0.3 to 0.7 (in 0.1 jumps).
Homework Equations...
I have understand that the Parallax method can be used to measure the distance to stars, but what happens when the parallax angle gets to small to be measures accurate?
What kind of methods are used to measure distance to star that are like 5000 light years away, or to Superclusters that are...
Homework Statement
I have made a solution to an exercise and I need some to check it and please notify me if I have made any misstakes.
Exercise
A satellite that is a black body, spherical and rotates around its own axis is send towards the Sun. How far will the satellite reach before its...
Homework Statement
I have made a solution to an exercise and I need some to check it and please notify me if I have made any misstakes.
Exercise
Calculate the radiation flux density of the surface of Earth from the sunlight that is reflected against the surface of Mars. As seen from the...
astronomy - conceptual, trigonometric parallax
Homework Statement
To determine a star's trigonometric parallax, we need at least 3 measurements of its position relative to much more distanct objects. Explain why this is true. (What else could change its position on the sky?)
Homework...
Hey all,
I am starting to think about colleges, it's a bit early for me (I'm entering 11th grade) but knowing which colleges I am seriously interested in would be a big help for a lot of reasons. I am absolutely sure I want to pursue a path in theoretical physics (not sure if that's the right...
Hi,
I'm a senior at the University of Wisconsin and I will be applying to grad school in physics soon. I'm currently majoring in Math, Physics, Nuclear Engineering, and Astronomy. I have 6 credits left to finish my astronomy degree and I'm seriously considering not finishing it out. As it...
Hello there! First post but I figure I'll get right into it. A lot of thoughts and I'd just like to see if anyone has done or seen anything similar. In 2006 I graduated with a BA in Radio, TV, & Film. I worked as a recording engineer (my initial career goal) for a few years, decided I liked...
hi - does it matter if you do research or not in astronomy as an undergrad? is it ok to just do undergrad physics research for astronomy grad school? does it look any better to do astronomy research versus physics research as an undergrad, or any physics will do? I'm asking as a matter of...
Hi guys,
I'm really interested in Astronomy related careers yet my parents want me to enter medicine due to its high pay. I'm a highly academic student and I am capable of entering medicine, however, I really want to do an astronomy/astrophysics course as I want to make a mark in the upper...
Get this, my Physics 191 book, which is basic astronomy
Here's the cover.
http://imageshack.us/photo/my-images/405/coverjgc.jpg/
Here's the side.
http://imageshack.us/photo/my-images/543/sidee.jpg/
Someone wasn't paying attention.
First of all this is NOT for class! Secondly, this seems rather simple, so perhaps I am simply overlooking the obvious. Anyway, here goes:
If some binary star is about 400 ly away, and a telescope gives a separation of 36" (0.01 degrees) for the binary, then can we use the small angle formula...
I have always been interested in astrophysics but my career took
another direction and I have an MS in computer science. I wanted
to go back and revive my interest. I have decent math/calculus
background, ODE, PDE, numerical methods including solving
PDE/ODEs, some linear algebra and...
As I understand Interferometry, a baseline does not refer to the distance between two RA scopes. It's the distance between two line of sites for each scope. They are parallel, when directed at the same object.
Suppose we have two scopes at two stations that are some distance apart, say...
Homework Statement
Expansion of the universe is described by the scale factor R(t), where t is the time after the Big Bang. For a flat universe the scale factor is today
R(t)=C_{1}\cdot t^{\frac{2}{3}}
When the Universe was radiation dominated, for t <200,000 years, the scale factor was...
I am currently a mechanical engineer student in greece.I really don't find mech eng. that interesting so i am willing( when i finish my 5 year study) to change field and study graduate astronomy.WIll i be able to do that?Also i really don't want to study again in undergraduate level.I am...
Hi,
Recently, at our department we formed a research group in Astronomy and Astrophysics with a bunch of young enthusiastic undergraduates who are keen on engaging in research work. Since not much research work in Astrophysics being carried out in Sri Lanka, the students are bit disappointed...
Hello, after recently graduating high school, I'm planning on going to college soon, and I got a couple of questions regarding Astronomy and Physics.
First, after recently getting interested in Astronomy, and always being interested in Physics, my question is how much is physics/mathematics...
Homework Statement
in about 6X10^7 y from now, the sun will be a red giant star with a temperature 1/2 its present value and a radius 100 times larger.
a) what will be the luminosity of the red giant sun be compared to its current value?
b) assume that the new luminosity gives you the...
Homework Statement
Hello I wanted clarification on freeman's law and the Tully fisher relationship.
Am i correct to say that the tully fisher relationship that states
L=kv^4 where L=luminosity of galaxy and v= max rotational speed of galaxy.
only applies to edge-on spiral galaxies...