Homework Help is Here – Start Your Trial Now!
Science
Advanced Physics
3. Consider a galaxy at a distance of 1.7 Mpc from Earth, in which the rotational velocity of the HI gas in the galactic plane at a distance of 20 kpc from the galactic centre has been measured to be 450 km s-!. (a) Use this information to estimate the mass of the galaxy. (b) Discuss whether your estimate provides an upper or lower limit on the total mass of the galaxy. Justify your answer. (c) Estimate the rotational velocity that HI gas would have at a distance of 30 kpc from the galaxy's centre. Clearly state any assumption that you make.

3. Consider a galaxy at a distance of 1.7 Mpc from Earth, in which the rotational velocity of the HI gas in the galactic plane at a distance of 20 kpc from the galactic centre has been measured to be 450 km s-!. (a) Use this information to estimate the mass of the galaxy. (b) Discuss whether your estimate provides an upper or lower limit on the total mass of the galaxy. Justify your answer. (c) Estimate the rotational velocity that HI gas would have at a distance of 30 kpc from the galaxy's centre. Clearly state any assumption that you make.

icon
Related questions
Question
de
3. Consider a galaxy at a distance of 1.7 Mpc from Earth, in which the rotational velocity of the HI gas in the galactic plane at a distance of 20 kpc from the galactic centre has been measured to be 450 km s-1. (a) Use this information to estimate the mass of the galaxy. (b) Discuss whether your estimate provides an upper or lower limit on the total mass of the galaxy. Justify your answer. (c) Estimate the rotational velocity that HI gas would have at a distance of 30 kpc from the galaxy's centre. Clearly state any assumption that you make. (d) If dark matter is comprised only of primordial black holes of mass 1013 kg, estimate the mean separation of the primordial black holes in this galaxy. Clearly state any assumption that you make. (e) Consider a type la supernova (SNla) that explodes in this galaxy, with a peak brightness 1.6 × 10ª higher than that of another SNla that was previously discovered in another galaxy at a redshift of z 0.05. Use this information %3| to estimate the Hubble constant.
Transcribed Image Text:3. Consider a galaxy at a distance of 1.7 Mpc from Earth, in which the rotational velocity of the HI gas in the galactic plane at a distance of 20 kpc from the galactic centre has been measured to be 450 km s-1. (a) Use this information to estimate the mass of the galaxy. (b) Discuss whether your estimate provides an upper or lower limit on the total mass of the galaxy. Justify your answer. (c) Estimate the rotational velocity that HI gas would have at a distance of 30 kpc from the galaxy's centre. Clearly state any assumption that you make. (d) If dark matter is comprised only of primordial black holes of mass 1013 kg, estimate the mean separation of the primordial black holes in this galaxy. Clearly state any assumption that you make. (e) Consider a type la supernova (SNla) that explodes in this galaxy, with a peak brightness 1.6 × 10ª higher than that of another SNla that was previously discovered in another galaxy at a redshift of z 0.05. Use this information %3| to estimate the Hubble constant.
Expert Solution
steps

Step by step

Solved in 4 steps

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer