# List of Y-dwarfs

This is a list of astronomical objects with the spectral type Y. They are a mix of brown dwarfs and planetary-mass objects. They are the coldest such objects in interstellar space and have a temperature around below 500 Kelvin (227°C; 440°F). Only a few are known due to their faint nature. The list is sorted after distance.
List of Y-dwarfs :
| Name | spectral type | T$_{eff}$ (Kelvin) | Mass estimate (M$_J$) | distance (light years) | Year of discovery |
| Jupiter | Y-class analog | 125 | 1 | solar system | known since ancient times |
| WISE J0855−0714 | Y4 (extrapolated) | 250 ± 50 | 3−10 | 7.43 ± 0.04 | 2014 |
| Epsilon Indi Ab | Y3 (estimated) | 275 | 6.31+0.60 −0.56 | 11.867±0.004 | 2018 (discovered) 2024 (imaging) |
| WISE J1639−6847 | Y0pec | 412 ± 88 | 5−14 or 9−17 | 15.45 ± 0.04 | 2012 |
| WISE J0350−5658 | Y1 | 388 ± 88 | 3−8 or 7−13 | 18.49 ± 0.24 | 2012 |
| WISEPA J1541−2250 | Y1 | 432+11 −18 | 8−20 | 18.9 ± 0.2 | 2011 |
| WISE J2209+2711 | Y0 | 371+9 −13 | 8−19 or 5 | 20.17 ± 0.25 | 2014 |
| WISEPC J1405+5534 | Y0.5 (pec?) | 412+10 −17 | 9−21 | 20.6 ± 0.3 | 2011 |
| WISEPA J0410+1502 | Y0 | 451 ±88 | 8−20 | 21.32 ± 0.10 | 2011 |
| WISE J0825+2805 | Y0.5 | 406+10 −16 | 3−8 or 5 | 21.4 ± 0.4 | 2015 |
| CWISE J1055+5443 | Y0 (pec) | 500 ± 150 | 4−6 | 22+3 −2 | 2023 |
| WISEPC J2056+1459 | Y0 | 510+14 −25 | 13−23 or 5 | 22.27 ± 0.07 | 2011 |
| WISEPA J1738+2732 | Y0 | 450 ± 88 | 5−14, 3−9 or 11−21 | 24.4 ± 0.2 | 2011 |
| WISEA J2354+0240 | Y1 | 362+10 −12 | 8−14 | 25.0 ± 0.6 | 2015 |
| CWISEP J0402−2651 | ≥Y1 (estimated) | 367 ± 79 | | 28.0+6.0 −4.2 | 2020 |
| WISENF J1936+0408 | Y0 (estimated) | 460 ± 79 | | 28.6+1.0 −0.9 | 2020 |
| WISE J0647−6232 | Y1 | 393 ± 88 | 5–13 | 29.6 ± 0.6 | 2013 |
| WISE J0713−2917 | Y0 | 464 ± 88 | 13−29 | 29.6 ± 0.2 | 2012 |
| WISEPC J1217+1626 B | Y0 | 460 ± 79 | 8−20 | 30.4 ± 1.0 | 2012 |
| WISEA J1930−2059 | ≥Y1 (estimated) | 367 ± 79 | | 30.7+1.5 −1.4 | 2020 |
| WISEA J1141−3326 | Y0 | 460 ± 79 | 3–8 | 31.4 ± 0.9 | 2014 |
| CWISEP J1446−2317 | Y1 | 366 ± 14 | 8.0 or 14.6 | 31.4+1.6 −1.4 | 2020 |
| CWISEP J2256+4002 | ≥Y1 (estimated) | 367 ± 79 | | 32.0+4.0 −3.2 | 2020 |
| WISEPA J1828+2650 | ≥Y2 | 406 ± 88 | 3–8 | 32.5+0.7 −0.6 | 2011 |
| WISE J0336−0143 A | Y0: | 460 ± 79 | 8.5–18 | 32.7 ± 0.7 | 2012 |
| WISE J0336−0143 B | Y2.5 (estimated) | 285–305 | 5–11.5 | 32.7 ± 0.7 | 2023 |
| WISEA J0830+2837 | ≥Y1 (estimated) | 367 ± 79 | 4−13 | 32.9+2.3 −2.0 | 2020 |
| WISEU J0503−5648 | ≥Y1 (estimated) | 367 ± 79 | | 33.2+1.4 −1.3 | 2020 |
| WISE J2220−3628 | Y0 | 452 ± 88 | 8–20 | 34.9 ± 0.4 | 2012 |
| CWISE J0925−4720 | Y0 (estimated) | 460 ± 79 | | ~35.0 | 2021 |
| CWISER J0216+4230 | Y0 (estimated) | 460 ± 79 | | ~35.2 | 2023 |
| CWISEP J0238−1332 | ≥Y1 (estimated) | 367 ± 79 | | 38+13 −8 | 2020 |
| WISE J1206+8401 | Y0 | 499+14 −24 | 6−14 or 12−22 | 38.5+1.0 −0.9 | 2015 |
| CWISE J2351−7000 | Y0 (estimated) | 460 ± 79 | | ~42.7 | 2020 |
| WISE J0359−5401 | Y0 | 468+13 −23 | 12−22 or 13 | 44.3 ± 1.2 | 2012 |
| WISE J0734−7157 | Y0 | 493+14 −24 | 9−20 | 44.5 ± 0.4 | 2012 |
| WISE J0304−2705 | Y0 pec | 465 ± 88 | | 44.6+1.6 −1.5 | 2014 |
| CWISEP J2230+2549 | ≥Y1 (estimated) | 367 ± 79 | | 46+13 −8 | 2020 |
| CWISEP J2011−4812 | Y0 (estimated) | 460 ± 79 | | 46 ± 2 | 2020 |
| CWISE J1811+6658 | early-Y (estimated) | 412 ± 79 | | 47+5 −4 | 2023 |
| CWISEP J1935−1546 | ≥Y1 (estimated) | 367 ± 79 | | 47+3 −2 | 2019 |
| WISE J0535−7500 | Y1 | 526+16 −26 | 8−20 or 12+18 | 47.5+1.4 −1.3 | 2012 |
| CWISEP J1047+5457 | Y1 | 415+20 −22 | 20.6 or 15.9 or 1–3 | 47.9+3.7 −3.2 | 2020 |
| CWISEP J0321+6932 | Y0.5 (estimated) | 412 ± 79 | | 48 ± 3 | 2020 |
| WISEA J2243−1458 | Y0 (estimated) | 460 ± 79 | | ~47.8 | 2020 |
| CWISEP J0938+0634 | Y0 (estimated) | 460 ± 79 | | 48+12 −8 | 2020 |
| CWISEP J0940+5233 | ≥Y1 (estimated) | 367 ± 79 | | 49+11 −8 | 2020 |
| CWISEP J0634+5049 | Y0 (estimated) | 460 ± 79 | | 53+4 −3 | 2020 |
| WISEA J1534−1043 | esdY0–esdY2 (estimated) | 447 ± 45 | | 53 ±4 | 2020 |
| WISEA J1257+7153 | ≥Y1 (estimated) | 367 ± 79 | | ~54.2 | 2020 |
| WISEA J0302−5817 | Y0: | 460 ± 79 | | 55 ± 3 | 2018 |
| CWISE J1531−3306 | Y0 (estimated) | 460 ± 79 | | ~55.4 | 2021 |
| CWISEP J2356−4814 | Y0.5 (estimated) | 412 ± 79 | | ~56.6 | 2020 |
| Ross 19 B | sdY (estimated) | 460 ±79 | 15−40 | 56.89 ± 0.04 | 2021 |
| WISE 0226-0211 B | T9.5 to Y0 (estimated) | 511 ±79 | | 57.9+2.7 −2.4 | 2019 |
| L 97-3 B | Y0 | 377 ± 88 | 7−9 | 62.73 ± 0.02 | 2011 |
| WISE J0146+4234 B | Y0 | 460 ± 79 | 8−20 | 63 ± 2 | 2015 |
| CWISE J2227+2604 | Y0 (estimated) | 460 ± 79 | | ~65.2 | 2023 |
| CWISEP J0859+5349 | Y0 (estimated) | 460 ± 79 | | 70+13 −14 | 2020 |
| CFBDSIR 1458+10 B | Y0 (estimated) | 370 ± 40 | 6–15 | 75.34 ± 7.83 | 2011 |
| CWISEP J0156+3255 | sdY (estimated) | | | 125+19 −17 | 2020/2024 |