 90Prime and DECam image of BD+60 1417 and the planet (red dot marked with a white arrow) | |
| Discovery | |
|---|---|
| Discovery date | 2021 |
| imaging method | |
| Designations | |
| W1243, CWISER J124332.12+600126.2 | |
| Orbital characteristics | |
| 2094 AU (inclination correction of 1.26)[1] | |
| Physical characteristics | |
| 1.29±0.06 RJ[2] | |
| Mass | 13.47±5.67 MJ[2] |
| 4.26±0.20[2] | |
| Temperature | 1240±81 K[2] |
Spectral type | L8γ |
| PanSTARRS y20.481±0.178 | |
BD+60 1417b is a confirmedexoplanet discovered in the year 2021 using theimaging method. BD+60 1417b is the only knownexoplanet in the system BD+60 1417, around 45parsecs fromEarth.[3] BD+60 1417 is a youngK0 star, while BD+60 1417 b has alate-L spectral type.[1][4] The planet might be the first discovery of a directly imaged exoplanet found by acitizen scientist. Discovery of exoplanets involving amateurs are usuallytransiting exoplanets and are rarely discovered with other methods. Another example of a non-transiting exoplanet discovery by an amateur is themicrolensing exoplanetKojima-1Lb.[5]
Previous direct imaging planet-searching surveys withGemini,Keck andPalomar failed to detect an exoplanet around BD+60 1417. A co-moving source around the star was first spotted with the WiseView Tool by theBackyard Worlds citizen scientist Jörg Schümann. WiseView uses data from theWide-Field Infrared Survey Explorer (WISE). Additional observations with optical spectroscopy of the star at theLick Observatory and infrared spectroscopy atNASA IRTF confirmed the presence of a young star with a planetary-mass companion around BD+60 1417.[1]
BD+60 1417b is the second directly imaged exoplanet the WISE-telescope was able to discover, afterCOCONUTS-2b.
The host star BD+60 1417 is a young K0 star with a mass of 1M☉ and a radius of 0.797 ±0.051R☉.[1] It has a brightness of 9.37 magnitude.[6] The star shows typical signs of youth, such asx-ray detection withROSAT[7] andlithium absorption lines. Its age is estimated at 50-150 Million years.[8] The star rotates with a period of 7.50 ± 0.86 days, which is seen due to evolvingstarspots in theTESS light curve.[1] The host star was observed with theLarge Binocular Telescope PEPSI instrument in 2023. This constrained several chemical abundances of the star, such as [Fe/H] = 0.27 ± 0.03 dex, C/O = 0.23 ± 0.12 and Mg/Si = 1.41 ± 0.19.[2]
BD+60 1417 is the onlymain sequence star with about one solar mass that is orbited by a planetary-mass object at a separation larger than 1000 astronomical units. All other systems with a separation >1000 au have a primary with <0.5 solar masses or are the stellar remnantWD0806.[1]
The infrared spectrum of the planet shows a red L8γ-type object withwater vapor,carbon monoxide,iron(I) hydride andpotassium iodide in its atmosphere. In the near-infrared it is one of the reddestsubstellar objects discovered to date with mag. The spectrum of the exoplanet closely resembles objects with a suspected low surface gravity. A low surface gravity is a sign of youth for substellar objects. The researchers also found similarities with an archivedSINFONI spectrum of the exoplanet2M1207b and spectra of theHR 8799 exoplanets.[1] The object was studied in 2024 and the team concluded that the model strongly favours a cloudy model over a cloudless model. Clouds offorsterite andenstatite should form on BD+60 1417b, if it has similar chemical abundances when compared to the host star.Quartz clouds should not form on this object. The researchers find that BD+60 1417b is spectroscopically very similar toWISEP J004701.06+680352.1, to the point that they call them spectroscopic twins.[2]
The planet has an orbital period of about 95,000 years.[9] BD+60 1417b has a large separation of 1662astronomical units from its host star. If this exoplanet has formed in this wide orbit, it is likely to have formed similar to isolatedbrown dwarfs. It could also have formed in a closer orbit around the star viacore accretion or disk instability and was later dynamically disturbed into a higher orbit, for example by aplanet-planet fly-by.[1]
According to theNASA Exoplanet Archive BD+60 1417b is an exoplanet[10] and it falls within their definition: An object with a minimum mass lower than 30Jupiter masses and a not free-floating object with sufficient follow-up.[11] The official working definition by theInternational Astronomical Union allows only exoplanets with a maximum mass of 13 Jupiter masses[12] and according to current knowledge BD+60 1417b could be more massive than this limit.
{{cite journal}}: CS1 maint: numeric names: authors list (link)Used inclination correction (1.26x1662 au)