A planet, possibly four times the mass of Jupiter and with a lunar system, could be lurking in our solar system's outermost area, two US scientists theorize。

　　University of Louisiana researchers said if "Tyche" exists, the confirmed number of planets in our solar system would return to nine, with Pluto remaining a dwarf planet, DiscoveryNews.com reported Wednesday。

　　Astrophysicists John Matese and Daniel Whitmire analyzed comets passing through the inner solar system, discovering many of them had strange orbits。

　　The scientists said they believe the comets' orbits could be affected by the potential mystery planet, composed of hydrogen and helium, likely sucked into our solar system after being formed around another star。

　　Matese and Whitmire have been trying to track down Tyche's existence since 1999, but the majority of the astronomical community hasn't expressed confidence about Tyche's existence, DiscoveryNews.com said。

　　Ned Wright, principal investigator for NASA's Wide-Field Infrared Survey Explorer mission, told DiscoveryNews the theory behind Tyche is based on "ordinary evidence for an extraordinary claim."

　　兩位美國(guó)科學(xué)家推斷太陽(yáng)系的遙遠(yuǎn)邊際還可能存在一顆星球，它大概是木星體積的四倍，擁有自己的衛(wèi)星系統(tǒng)。

　　《發(fā)現(xiàn)新聞》網(wǎng)站周三報(bào)道，路易斯安娜大學(xué)的研究者稱如果這顆稱為"堤喀"的星球真的存在，加上冥王星這個(gè)矮行星，太陽(yáng)系的星球數(shù)量將變?yōu)?顆。

　　天體物理學(xué)家約翰?馬特斯和丹尼爾?惠特米爾分析了太陽(yáng)系內(nèi)部的彗星運(yùn)轉(zhuǎn)，發(fā)現(xiàn)許多彗星的運(yùn)行軌道都非常奇特。

　　科學(xué)家們稱他們認(rèn)為彗星軌道可能受到這顆未知星球的影響，這顆星球主要由氫氣和氦氣組成，可能在另一顆星球旁形成后被吸入太陽(yáng)系。

　　這家網(wǎng)站報(bào)道稱馬特斯和惠特米爾自從1999年以來(lái)一直試圖證明堤喀的存在，但大部分天文界人士對(duì)它的存在將信將疑。

　　美國(guó)宇航局大視場(chǎng)紅外巡天探測(cè)者計(jì)劃的主要調(diào)查者內(nèi)德?萊特對(duì)《發(fā)現(xiàn)新聞》說(shuō)這項(xiàng)關(guān)于堤喀的理論是基于"大膽的設(shè)想和實(shí)在的證據(jù)"。