B2 1215+30 multiwavelength SED

B2 1215+30 is a BL Lac object at redshift z = 0.130. Its MMDC SED has 6,694 points from 49 catalogues, with dated data from 1998–⁠2025. Download the SED as CSV.

Updated 29 October 2026.

Names and position

Also known as 1ES 1215+303, 1FGL J1217.7+3007, 1FLAT J121752.1+300700, 2FGL J1217.8+3006, 2FHL J1217.9+3006, 2WHSP J121752.0+300700, 3FGL J1217.8+3007, 5BZB J1217+3007, BZB J1217+3007, CRATES J121752+300657, EXO1215.3+3022, ON325, RBS1093, TXS 1215+303.

Class: BL Lac
Redshift: z = 0.130
Position (ICRS): RA 184.46701°, Dec 30.11684°
Galactic: l 188.875°, b 82.053°

Other names and measurements: NED and SIMBAD within 5″ of this position.

The SED

Data: 6,694 points (48 upper limits) from 49 catalogues
Dated data: 1998–2025 (MJD 51170–60967)
Undated catalogue values: 140
Frequency range of detections: log ν = 7.9–26.2 [Hz] (radio, microwave, infrared, optical, ultraviolet, X-ray, γ-ray)
Swift measurements analysed by MMDC: 220 UVOT and 193 XRT
Largest catalogues (points): ZTF (4,779), NEOWISE (614), MMDCGR (287), MMDCXRT_ORBIT (272), MMDCXRT (168)

Data by band

All 7 bands have data. The infrared band has the most points, 5,571 of 6,694; its largest catalogue is ZTF with 4,779.

Band	Points	Catalogues	Dated data
radio	28	10	undated
microwave	19	6	2015–2016
infrared	5,571	11	2010–2025
optical	118	3	2009–2021
ultraviolet	2	1	undated
X-ray	641	13	1998–2017
γ-ray	315	5	2008–2025

Get the data

The SED as CSV from the MMDC SED API (docs.mmdc.am).

In Python, with astro-mmdc:

from astro_mmdc import MMDC
sed = MMDC().sed.get(ra=184.46701, dec=30.11684, name="B2 1215+30")

The interactive SED plot, with time filtering and modeling (needs JavaScript).

Nearby sources

PG 1218+304, 46′ away
W Comae, 2.0° away
B2 1229+29, 3.3° away
Ton 599, 4.1° away

Other BL Lac objects

How to cite

Sahakyan, N., Vardanyan, V., Giommi, P., et al. 2024, AJ, 168, 289, doi:10.3847/1538-3881/ad8231 (arXiv:2410.01207).