Observed Spectral profile of NGC4151
| Date & Time: | Jan 21 2023, from 25:44 to 25:54 JST(+0900) |
| Composed 2 shots with 10 minutes exposed |
| Optical: | Meade 25cm(10") Schmidt Cassegrain (f=2500mm, F10.0) |
| with SBIG DSS7 Spectrometer |
| Auto-guided with Meade LX200 Equatorial & Lacerta M-GEN |
| Cooled CCD Camera: | SBIG ST-402ME (Temp.: -25°C) |
| Location: | Ooizumi, Hokuto city, Yamanashi pref. |
Upper strip: taken spectrogram, Lower strip: stretched 3-pixel-width & pseudo-colored image
| Emission line | Hα | Hβ | O III | O III | S II |
|---|
| Observed WL, λm | 6588.0 Å | 4879.8 Å | 4979.0 Å | 5026.1 Å | 6754.9 Å |
| WL in literature, λ0 | 6562.9 Å | 4861.3 Å | 4959 Å | 5007 Å | 6730 Å |
| Red shift, z | 3.825×10-3 | 3.806×10-3 | 4.033×10-3 | 3.815×10-3 | 3.700×10-3 |
| Recession velocity, v (km/s) | 1.145×103 | 1.139×103 | 1.207×103 | 1.142×103 | 1.108×103 |
| Estimated distance, D (Mly) | 53.33 | 53.07 | 56.23 | 53.19 | 51.60 |
| (average) | 53.49 Mly |
|---|
z= (λm-λ0)/λ0
v= c*((1+z)2-1)/((1+z)2+1)
D= 3.26*v/H0 (Mly)
(c: velocity of light, H0=70 km/s/Mpc)
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This page shows you the observed spectral profile of NGC4151. Generally the seyfert galaxies including NGC4151 have wealth of inter-stellar gaseous matters.
We can detect clear emission lines like diffused and/or planetary nebulae, can easily estimate distances to the galaxies from red shifts of those lines.
A table in right has listed and indicated estimated distance to NGC4151 from observed wavelengths of five lines.
The value can be calculated as about 53.5 million light years under an assumption that the Hubble constant of H0 has 70 km/s/Mpc.
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