One caveat is that both HD 100546 b and c reside within the dusty, doughnut-shaped disk of planet-forming material that surrounds their parent star, rather than in the inner, dust-free cavity. “Our images provide a glimpse into how material from the natal protoplanetary disk gets incorporated into planets with masses and separations like HR 8799’s,” he noted. Marois and his colleagues imaged that exoplanet system, the first to be photographed, in 2008.Įvidence in the images suggests that at least one planet in the newfound HD 100546 system is surrounded by a feeding disk of planet formation material, said Currie. He likened the HD 100546 system to an infant version of an older planetary system, HR 8799. Further observations are needed to determine this object’s identity, which could be no heavier than 10 to 20 times the mass of Jupiter, Currie said. The researchers also discovered a second object, a candidate infant planet that lies roughly 14 AU from the star, or about 1.5 times Saturn’s distance from the Sun. “We know so little about what a growing planet looks like that it’s hard to understand what is being seen,” he cautioned. The infrared light detected from HD 100546 b “is apparently some combination of emission from a planet-forming disk and a growing planet,” said astronomer Mark Marley of NASA’s Ames Research Center in Mountain View, Calif., who was not involved with the research. Moreover, the reddish color of the planet, observed at infrared wavelengths, hints that this infant world, although it’s already up to 3 to 4 times as massive as Jupiter, is still growing. The parent star is a youthful 10 million years old (our middle-aged solar system is 4.56 billion years old) and still retains part of its doughnut-shaped planet-forming disk. The confirmed planet, first identified in 2013 and known as HD 100546 b, lies about 47 astronomical units (AU) from its parent star, farther than Pluto’s distance from the Sun (1 AU is the distance between Earth and the Sun). Credit: Gemini Observatory/AURA/Thayne Currie – NAOJ It could weigh in at up to 10–20 Jupiter masses. (bottom) The recent images of the surroundings of HD 100546 (the star) have revealed what appears to be a second still-growing planet, dubbed HD 100546 c. Credit: Gemini Observatory/AURA/Thayne Currie – NAOJ (top) New observations have confirmed that the object HD 100546 b, which is up to 3–4 times as massive as Jupiter and orbits a youthful star some 320 light-years from Earth, is a still-forming planet. (top) New observations have confirmed that the object HD 100546 b, which is up to 3–4 times as massive as Jupiter and orbits a youthful star some 320 light-years from Earth, is a still-forming planet. Get the most fascinating science news stories of the week in your inbox every Friday. “These two discoveries are showing us, for the first time, a new piece of the puzzle to understand the planet formation process,” said Christian Marois of the National Research Council of Canada’s Herzberg Institute of Astrophysics in Victoria, British Columbia, who was not part of either study. The recently published findings have come out in rapid succession within weeks of the 20th anniversary of the 23 November 1995 publication of the discovery of the first planet orbiting a Sun-like star. Images of the fledgling planets, which reside in separate star systems a few hundred light-years from Earth, reveal that the babies are still feeding off of material from their birth clouds-swirling disks of gas and dust that encircle their young parent stars. Now two teams of researchers have independently taken the first-ever snapshots of infant planets still nestled in the womb around their parent stars. The babies are still feeding off of material from their birth clouds-swirling disks of gas and dust that encircle their young parent stars. However, the very first page in the exoplanet photo album-the portrait of an infant-remained blank. For nearly a decade, astronomers have taken pictures of young planets orbiting stars beyond the solar system.
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