Astronomy Definition and 805 Threads

Hi There, I am working on my second novel, a kind of Buck Rogers-type adventure, and I want to make sure that I'm being at least reasonbly accurate in regard to what an "outer space" journey might be like. It's going to be light in tone and I'm not looking to get into lots of particle talk...

Homework Statement I'm wanting to convert barycentric julian date to the equivalent UT time. Here is a description of the barycentric julian date given to us: Barycentric Julian Date (TT) – Observation epoch, given in terrestrial time, that has been corrected for light propagation time to...

I am a high school student right now (11th grade) and I am really interested in studying Astronomy and Physics. I asked my Astrophysics teacher if NASA has Astronomy jobs, and I believe he said that it would lean more into Physics or "Astrophysics" And he said that they look for people with...

I cannot figure out the answers for the following problems: 1) If a star has a parrallax of 0.016 second of arc and an apparent magnitude of 6, how far away is it, and what is its absolute magnitude? 7) If a star is 10 times the radius of the sun and half as hot, what will its luminosity be...

Homework Statement When the Sun becomes a red giant star its brightness will increase by a factor of 5000 and its mass will decrease to half of its present mass. When this happens particles smaller than a critical size will be blown out (light force = gravity force) of the solar system by the...

Homework Statement An airliner flies from London Heathrow (latitude 51^{o}30' N, longitude 0^{o} 10' W) to Tokyo Narita (latitude 35^{o} 40' N, longitude 139^{o} 45' E). Assuming that the Earth is spherical and the aeroplane takes a great circle route, a)what is the total distance flown...

[SOLVED] Astronomy Question Homework Statement This is a two part question. I believe the problem I'm running into is coming from the answer to the first question. Q1: Hold your hand 7.5 cm from a 100 watt light bulb and you will feel the same heat sensation that you feel when your hand is...

I am having a hard time with these astronomy questions. Our teacher gives us no help and I am lost with this stuff. If anybody could help me out not just with the answer but on How to do it I would be most appreciative. What would be the frequency of an electromagnetic wave having a...

I am looking at a cheap $100 shortwave radio, the Kaito KA-2100 (google it, there are a bunch of links, too many to mention), and I would like to know if disabling the AGC (automatic gain control), is possible for use as a radio telescope. Now I don't know that much about radio and electronics...

A few days ago I guess I got to a new article regarded to astronomy in Yahoo! I don't remember exactly what was the title since I just had a glance at that and didn't have enough time to read it but it seemed to me there was something like "planets splash the satrs(eh?) like flies splash...

Homework Statement I'm absolutely desperate for help on this. The image supplied below is an image of a frequency histogram for the V-band Tycho photometry data (from the Tycho Epoch Photometry Annex). What I've done is this: 1. I've converted the V-band magnitudes into flux so that it is...

Homework Statement My class is doing an assignment where we have to create a programme to convert the Hipparcos data from magnitudes to flux so that it when you plot a frequency histogram of the data you will have an approximation of a normal distribution. I've completed this OK, but I was...

I didn't realize there was such "animosity". http://www.nature.com/nature/journal/v447/n7141/full/447122a.html" in this week's edition of Nature (the link is open without subscription only for a short time). So, for people who are majoring or working in this field, do you share White's...

I have a question about dead stars. I have only read about 2 ways a star can die. Either explode into a supernova or collapse into a black hole. It seems strange to me that when a star consumes all its energy that it could not simply become a huge lump of slag out there. Is it possible that...

i have 2 questions: 1. what is the difference between astronomy, astrophysics and cosmology? 2. what did Alan Guth mean when he said, "The universe is the ultimate free lunch"?

Homework Statement Compare this to the power received on the ground from a geostationary satellite with a 1 W transmitter and with a transmission footprint of 1000 square km across (assume uniform power in footprint). The Attempt at a Solution I don't know where to start on this one...

i have been trying to do this problem for an hour and i have no clue what to do for it... please help me It's on the 4th page down and it is called "Spectroscopic eclipsing Binary System" htt p://www.tufts.edu/as/wright_center/fellows/sci_olympiad/Spok_2000_C_Instrcs_&_Quests.pdf...

Hey guys, Do any of you know a free database with a wide variety of journal articles that I can search? I want the full text articles, but most databases search abstracts and then give you a link to a site where you have to pay for the full text version. I mean I am told of these...

Having seen the horrors of long times between posts, and the starving databanks ready for more information, I am officially moving to the astronomy section. My experience may be questioned, but I can assure you that I do know a lot about Space in general, even though my AstroPhysics is...

Recently I gave my Astronomy Olympiad. There were some questions of descriptive type. If you all don't mind I would like to discuss them here. :rolleyes:

Homework Statement The hydrogen atoms in a star are also moving at high velocity because of the random motions caused by their high temperature. As a result, each atom is Doppler shifted a little bit differently, leading to a finite width of each spectral line, such as the 656.46-nm line we...

Alright, basically you have to think of a song that in some way relates to a planet, star, moon, astronomer, concept, theory, astronomical term, etc. Expect some to be funny. I'll start off: I still haven't found what I'm looking for - U2 - Dark matter/energy Here comes the Sun - The Beatles...

Hello all, I am currently doing a 3rd year Astronomy and Astrophysics course and I am having some trouble with the current problem set (this is mainly because our teacher doesn't really teach us anything but that's another story). This is the question in particular that is bothering me...

For an astronomy lab I am looking at pictures of the moon, measuring pixel distances and converting to km. Easy enough for the diameter of a crater, but the depth gets more complicated. To find the wall height of the crater, you measure the shadow length and the angle of altitude (theta in...

Hi all, I'm stuck on this question for my assginment...i need to derive the velocity at perhelion and aphelion using two separate methods: the conservation of specific angular momentum and energy. I think I'm OK with the energy part but I'm stuck on getting the velocities at aphelion and...

Q.1 If the mass of the sun is reduced by 1% and the Earth's velocity is also reduced by 1%, what will be the trajectory of the earth?

I want to know what is different between nebula and a death star?

I am planning to puruse the Distance Education Astronomy course (MSc in Astronomy) offered by Swinburne University of Australia (SAO). I already have a Master's degree in Chemistry (post graduate thesis being part of this) and a Bachelor's degree in Electronics from a reputed Indian University...

Saturn's rings backlit. You can see ALL the rings in glorious detail and light. It's beautiful. http://www.badastronomy.com/pix/bablog/2006/saturn_backlit_glow ...Any other amazing pictures?

I'm taking Astr. 321 right now. We were supposed to read the first 3 chapters. They go through the different planets (some detail, but nothing too complicated), the sun, asteroids, etc. The lectures went over this in more detail and went through things like which elements were created first...

Question: I live in west Los Angeles, and I was wondering if I would be able to see much at all with a personal telescope, if I got one. I imagine the light pollution would prevent me from observing anything but the brightest of objects (Moon, Venus, Polaris, etc). Has anyone attempting to do...

Hi all, Does anyone knows of any Astronomy graduate who earn Phd or Bsc or Msc at age between 35-45? Whats the oldest age ever to get Astro Phd? I have a Bachelor of Science in Physics ( Boston , MA) and I am 37 years of age, I have applied ( sucessful application) to do Master ( One...

SpaceTiger's Note: Taken from https://www.physicsforums.com/showthread.php?t=130680" Sorry, this question is somewhat off-topic, but aren't the arxiv.org-papers peer-reviewed?

I am a 22 yr old girl. I just went back to college and I am double majoring in aeronautical engineering and astronomy. I am little confused as how to strt getting internships and such in my field. Also, I don't really know how to go about having a career in astronomy. I do realize that i'll be...

Is traveling a big deal when your an astronomer?

Hello, I'm in the midst of choosing technical electives (in the Engineering Physics program). I am just wondering what sorts of Electrical Engineering topics might be applicable to astrophysics, or space science in general? I hope this question is not too vague, but I have a choice of...

If you were trapped deep under the surface of a geologically dead rocky (say, Mars, or Mercury) or icy (say, Callisto, or Charon) planet-sized body, say 10 to 1,000 km down, what could you determine about the rest of the universe (and the place of your home in it)? Assume that you have...

NOTE by SpaceTiger: Split from the "Nasa" thread started by wolram. Here, we'll explore the question of the relation between seemingly disconnected areas of astronomical research. I respectfully suggest these are actually interrelated ideas. By better understanding what the planets are made...

Astronomy Problems: Please Help! THESE ARE ALSO POSTED ON THE HOMEWORK PAGE WITH NOTES ABOUT WHAT I HAVE DONE. 1.) If a star has a temperature only 7/10 that of our Sun but a radius 10 times our Sun's, how would its luminosity compare to our Sun? 2.) If a star has a mass 11 times our Sun's...

Hi all, I'm currently working on a uni essay, the subject of which is how the properties of light are (and have been) used to discover and observe objects in astronomy. So far I'm looking into how the value of c is used, how doppler shift is used to determine velocities, how looking at the...

I need to access a star catalogue on the internet that will tell me the distance of the stars from earth, as well as the mass of the stars. I need to "find" 2 stars: approx. 346.7 pc from Earth approx. 0.4786 pc from Earth I realize that there may be none. However, the point of the...

1.) The frequency of WUSC is 90.5 x 10^5 cycles per second. What is the wavelength? I used C = wavelength (frequency) Thus: 3x10^8 m/s = wavelength (90.5 x 10^5) wavelength = 3.314917127 m wavelength = 3.31 x 10^9 meters 2.) If the period for a certain satellite revolving in a polar...

Try talking about astro phys to *the man in the street*, and there is no interest whatsoever, how can this be redressed ? i can tell you the black eyed peas are more of interest to the GP.

yes, i am defintely not a genius at this stuff... i am having some problems figuring these two problems out: Earth is 1.5x10^11 m from the Sun and has a period of 365.2 days. Mars is an average of 2.28x10^11 km from the sun. what is the orbital period of Mars in Earth years? i am not...

I've been reading over my astronomy coursework and trying some questions, and I'm coming across a few things I'm not sure about, i'd be grateful if you could provide the answers. 1/ Give three possible astrophysical reasons for periodic variations in the observed photometric signal from a...

1. If a comet has an eccentricity of 0.98 and a semimajor axis of 12 AU, what are the apehlion and perihelion distances? What is the period? How does the velocity at perihelion compare to the velocity at aphelion? In this problem, I used the perihelion and aphelion equations to solve for...

I'm not sure if this is a correct forum for this topic, but I'm wondering if there is any research done on VLF (very low frequency) radio astronomy. Obviously, such telescope would have to be in space, because all signals up to 15 MHz are reflected by the atmosphere. If this was done or not...

Introductory Astronomy & Astrophysics by Zeilkik and Gregory 4th edition. What are your opinions on this book? As far as I know the field has changed dramatically over the years and I was wondering if I should get a better or newer book since it was published in 98. I also heard it had a...

http://www.space.com/spacenews/businessmonday_051121.html" A $1 billion dollar cost growth on the mission is a lot, but considering the value and continuing contributions of Hubble to this very day, I think we can all agree that the JWST is a priority mission for NASA’s universe division...

Given equations: \frac{d T^4}{dr} = - \frac{3 \kappa \rho}{a c} F_{rad} where a = 4 \sigma_{B} / c with \sigma_{B} being the Boltzmann constant. Also, define the optical depth \tau = \int \kappa \rho dr Optical depth measured at ground level is \tau_{g} Where \tau_{g} = \int^\infty_{ground}...