Astronomy C

jonboyage
Member
Member
Posts: 71
Joined: Tue Dec 13, 2016 4:32 pm
Division: C
State: PA
Contact:

Re: Astronomy C

Postby jonboyage » Fri Jan 12, 2018 11:12 pm

PM2017 wrote:
Adi1008 wrote:
ashucha wrote:This may be a bit too specific but does anybody know what the apparent and absolute magnitude of DEM L241 (aka NGC 2029) is and where you got this information? Thanks!

This isn't anywhere close to perfect, but perhaps it's a reasonable estimate.

This paper says that the x-ray source has a luminosity . Converting that to absolute magnitude gives about 0.54

The same paper also mentions that the distance is about 50 kpc. Using the distance modulus, this gives an apparent magnitude of about 19.03

As for the entire remnant, Table 5 in the paper says that it has a luminosity of about . This would give an absolute magnitude of about -1.11 and apparent magnitude 17.385


Correct me if I'm wrong, but simbad seems to give an apparent magnitude of 12.29.
http://simbad.u-strasbg.fr/simbad/sim-id?Ident=NGC++2029

this would imply an absolute magnitude of -6.20, using the distance modulus (with d= 50,000 pc, from the aforementioned paper)


I would tend to believe PM2017 because later in the paper it says, "The bright optical counterpart, a V = 13.5 O5III(f) star, is
easily visible within the Head of the remnant." The star probably emits a lot of ionizing radiation and lights up, so-to-speak, the rest of the nebula. Note that SIMBAD lists the magnitude in the J band, which is infrared, so that makes sense.
Bayard Rustin High School! :D

I am in a bin

PM2017
Member
Member
Posts: 83
Joined: Sat Jan 21, 2017 1:02 am
State: -
Contact:

Re: Astronomy C

Postby PM2017 » Sat Jan 13, 2018 12:21 am

jonboyage wrote:
PM2017 wrote:
Adi1008 wrote:This isn't anywhere close to perfect, but perhaps it's a reasonable estimate.

This paper says that the x-ray source has a luminosity . Converting that to absolute magnitude gives about 0.54

The same paper also mentions that the distance is about 50 kpc. Using the distance modulus, this gives an apparent magnitude of about 19.03

As for the entire remnant, Table 5 in the paper says that it has a luminosity of about . This would give an absolute magnitude of about -1.11 and apparent magnitude 17.385


Correct me if I'm wrong, but simbad seems to give an apparent magnitude of 12.29.
http://simbad.u-strasbg.fr/simbad/sim-id?Ident=NGC++2029

this would imply an absolute magnitude of -6.20, using the distance modulus (with d= 50,000 pc, from the aforementioned paper)


I would tend to believe PM2017 because later in the paper it says, "The bright optical counterpart, a V = 13.5 O5III(f) star, is
easily visible within the Head of the remnant." The star probably emits a lot of ionizing radiation and lights up, so-to-speak, the rest of the nebula. Note that SIMBAD lists the magnitude in the J band, which is infrared, so that makes sense.

Also the fact that Wikipedia uses SIMBAD as a source, so many test-makers will expect that value.
2018 Events : Astronomy, Mousetrap Vehicle, Mission Possible, Fermi Questions

Favorite Inspirational Quote: "Start by doing what's necessary; then do what's possible; and suddenly you are doing the impossible." (Attributed to St. Francis of Assisi)

User avatar
Adi1008
Exalted Member
Exalted Member
Posts: 323
Joined: Fri Dec 06, 2013 9:56 pm
Division: C
State: TX
Location: Katy, Texas
Contact:

Re: Astronomy C

Postby Adi1008 » Sat Jan 13, 2018 1:55 am

PM2017 wrote:
jonboyage wrote:
PM2017 wrote:
Correct me if I'm wrong, but simbad seems to give an apparent magnitude of 12.29.
http://simbad.u-strasbg.fr/simbad/sim-id?Ident=NGC++2029

this would imply an absolute magnitude of -6.20, using the distance modulus (with d= 50,000 pc, from the aforementioned paper)


I would tend to believe PM2017 because later in the paper it says, "The bright optical counterpart, a V = 13.5 O5III(f) star, is
easily visible within the Head of the remnant." The star probably emits a lot of ionizing radiation and lights up, so-to-speak, the rest of the nebula. Note that SIMBAD lists the magnitude in the J band, which is infrared, so that makes sense.

Also the fact that Wikipedia uses SIMBAD as a source, so many test-makers will expect that value.

Looks like I was completely wrong then xD

jonboyage and PM2017's stuff seems much more reasonable
Seven Lakes High School '18

syo_astro
Exalted Member
Exalted Member
Posts: 489
Joined: Sun Dec 04, 2011 5:45 am
Division: Grad
State: NY
Contact:

Re: Astronomy C

Postby syo_astro » Sat Jan 13, 2018 4:51 am

Welp, my internet was bad and post got deleted...so I'll try to summarize before internet goes out...

Adi: That sucks, happens to me too. Would be careful about the paper and other papers because it seems to focus a lot on the X-ray spectrum (and even calls the luminosity "Lx"). While paper reading can help, interpreting the results and data yourself can be a dangerous endeavor, tread carefully. I leave the rest to you all;).

Others: Not sure about that app. mag...no reference seems to be listed, but I guess maybe lots would be satisfied stopping there (though, if you want, feel free to dig deeper!...I won't right now). Question then: Do many test writers ask to give an app. mag. for a random DSO or to calculate the abs. mag for a random DSO (showing work or something)? It's a bit of an odd question, but I got my share of odd questions when I competed. I wouldn't be too surprised.

Fun fact: Alpha, me, someone from Troy I didn't get to see were at an astro conference! It's the American Astronomical Society / AAS conference, and we all presented our research:). Sadly, didn't take a look at many of the black holes / compact objects talks...that said, I should probably get test writing for everyone ASAP >.<.
Past Events
B: Crave the Wave, Environmental Chemistry, Robo-Cross, Meteorology, Physical Science Lab, Solar System, DyPlan (E and V), Shock Value
C: Microbe Mission, DyPlan (Earth's Fresh Waters), Fermi Questions, GeoMaps, Gravity Vehicle, Scrambler, Rocks, Astronomy
Grad: Writing Tests/Supervising


Return to “Study Events”

Who is online

Users browsing this forum: No registered users and 1 guest