Interstellar medium Definition and 17 Threads

If I'm not mistaken, in interstellar gas, there can be clouds of free electrons (not "attached" to any atomic nucleus) But can they stay like that indefinetely? Or will they inevitably end up in atoms? And how are they holding in interstellar gas inside of galaxies? Are they gravitationally...

Interstellar dust prevents us from seeing most of the light of the Milky Way. Does anyone know how bright it would look if it had no dust at all? As it is, the Milky Way is impossible to see from cities and many suburbs, but how would the situation improve if there were no dust between the stars?

I understand that the interstellar medium (ISM) consists mostly of neutral hydrogen gas, plus a smaller fraction of helium gas. Furthermore, I gather that between 0.1 and 1.0 atoms per cm3 correspond to the average density values pertaining in our "Local Bubble". The above, however, refers...

I recently came across a paper where there was a term ''stochastic heating of very small grains". I went through some papers on this area but I am still confused about it. What is the vibrational temperature associated with very small grains? Does temperature has got a meaning if it's a highly...

1. Question Suppose you examined the spectrum of some nebulosity surrounding a main-sequence spectral-type O star and found that it contained no emission lines, only the continuous spectrum of the star. What conclusions could you draw about the nature of the interstellar material around that...

I hope putting this in the high energy section is the right section (if not, please let me know which would be more appropriate!) I felt this was appropriate since the work I am doing is high energy astrophysics. So I'm doing some research this summer, and my tasks were to take some data...

In 2008, astronomers discovered that a multi-million-solar-mass cloud named Smith's Cloud would hit the Milky Way's disk in about 27 million years. Now new Hubble observations have identified the mysterious cloud's likely origin. Link: New Scientist

Hello everyone, this is my first poster here. I met this problem when I was attending class of interstellar medium, and I was confused by the question.

Homework Statement Answer the following questions. Pleas show all of your work and your line of thinking and state your assumptions. There are several phases of the ISM. Consider the following three phases with different typical number densities ## n ## and temperatures ## T ##. The cold...

Homework Statement Show that the solution of the form ρ1 = ρ1(x±a0t) satisfy the equation: ∂2ρ1/∂t2 - a02∂2ρ1/∂x2 = 0 and that they correspond to waves propagating in the directions x increasing or decreasing. Homework Equations P = P0 + P1 ρ = ρ0 + ρ1 u = u1 The Attempt at a Solution P1 =...

So, I've read here http://en.wikipedia.org/wiki/Interstellar_medium that the Interstellar medium varies greatly throughout space. Of the categories listed; Molecular clouds, Warm Neutral Medium, Clound Neutral Medium, Warm Ionized Medium, H II regions, and Coronal Gas/Hot Ionized Medium...

Somewhere in our Galaxy resides a cloud of neutral hydrogen gas with a radius of 10 pc. The gas density is 10^7 atoms/m^3. (a)How many 21-cm photons does the cloud emit every second? (b)If the cloud is 100 pc from the Sun, what is the energy flux of this radiation (in W/m^2) at the Sun...

Hey, can anybody tell me what the estimate is on the mean mass of a particle in the interstellar medium? I would guess around 1-10 proton masses?

Hi all, I am writing you because in my research I need to characterize the space environment for an interstellar flight from the Earth to Alpha Centauri (more exactly proxima centauri). So i need densities of atoms and ions (in terms of cm^-3), energies (MeV), magnetic field strength...

Hi all. First post and all that, so I hope I don't do anything wrong, and that if I do, you'll cut me a little slack :P Anyway, onto the question I'm wanting help with: A J-shock in a Herbig-Haro object is propagating through neutral hydrogen gas at speed 100km/s. The gas has number...

I am trying to get a basic understanding of the physics of the interstellar medium and the current models which describe it (FGH and McKee-Ostriker). A first question arises regarding the possible assumption of a gas in ionization equilibrium, in which ionizarion and recombination occur at...

Originally posted in College Level Homework help but I got no responses there. Please help if you can. I am studying for my qualifier and doing problems out of Jackson. I am stuck on this one... any help would really be appreciated... I am unsure how to begin: Jackson 7.15 The partially...