原文链接：https://www.nasa.gov/feature/goddard/2017/nasa-funded-citizen-science-project-discovers-new-brown-dwarf

2017年 7月17日

One night three months ago, Rosa Castro finished her dinner, opened her laptop, and uncovered a novel object that was neither planet nor star. Therapist by day and amateur astronomer by night, Castro joined the NASA-funded Backyard Worlds: Planet 9 citizen science project when it began in February — not knowing she would become one of four volunteers to help identify the project’s first brown dwarf, formally known as WISEA J110125.95+540052.8.

六个月（原文是3个月，但是距离2月已经过去6个月了）前的一个晚上，Rosa Castro在晚餐后打开笔记本电脑，发现了一项无关行星与恒星的新兴项目。Castro在白天是一位临床医学家，到了晚上她便化身为天文爱好者。Castro加入了于二月开始的，由NASA资助的“后院世界：行星9号公民科学家项目”，在那时，她还不知道她将成为这项计划中四位鉴定褐矮星WISEA J110125.95+540052.8的志愿者之一。

概念图显示褐矮星的平均大小比太阳小很多，质量低，体积比木星稍大。

 

After devoting hours to skimming online, publicly available “flipbooks” containing time-lapse images, she spotted a moving object unlike any other. The search process involves fixating on countless colorful dots, she explained. When an object is different, it simply stands out. Castro, who describes herself as extremely detail oriented, has contributed nearly 100 classifications to this specific project.

“后院世界”的网站上有制作成“翻页书”供公众浏览的延时摄影图片，在贡献了几个小时的观察之后，Castro圈出了一个不像其他星体的移动物体。“这项搜索工作包括注视无数彩点，”Castro如此解释，“如果有一个不同的物体，它只是简单的出现在那里。”Castro认为她自己是极端注重细节的，在这项特殊的工作中，她贡献了自己100%的注意力。

最新被发现的褐矮星WISEA J110125.95+540052.8（图中被圈出的白点）在“后院世界：行星9号公民科学家项目”的动画化的翻页书中是一个移动的点。

 

A paper about the new brown dwarf was published on May 24 in The Astrophysical Journal Letters. Four citizen scientists are co-authors of the paper, including Castro. Since then, Backyard Worlds: Planet 9 has identified roughly 117 additional brown dwarf candidates.

关于这颗褐矮星的论文发表于5月24日的《天文物理期刊》，由包括Castro在内的四位公民科学家联合署名。从那时起，“后院世界：行星9号公民科学家项目”已经鉴定出差不多117颗可能是未被发现的褐矮星的星体。

 

 

The collaboration was inspired by the recently proposed ninth planet, possibly orbiting at the fringes of our solar system beyond Pluto.

这项合作是由近期一项寻找太阳系边缘、冥王星以外，可能存在的第九行星轨道的提议所启发。

 

“We realized we could do a much better job identifying Planet Nine if we opened the search to the public,” said lead researcher Marc Kuchner, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Along the way, we’re hoping to find thousands of interesting brown dwarfs.”

“我们认为，如果我们把一些搜索项目对公众开放，我们可能能把鉴定第九行星的工作发挥得更好。”首席研究员，NASA戈达德太空飞行中心天体物理学家Marc Kuchner说，“用这种方法，我们希望能找到上千颗有趣的褐矮星。”

 

It’s been roughly two decades since researchers first discovered brown dwarfs, and the scientific community opened its eyes to this new class of objects between stars and planets. Although they are as common as stars and form in much the same way, brown dwarfs lack the mass necessary to sustain nuclear fusion reactions. They therefore do not have the energy to maintain their luminosity, so they slowly cool over the course of their lifetimes. Their low temperatures also render them intrinsically dim.

自研究人员发现第一颗褐矮星起，已经过去了近二十年，现在，科学家群体正关注着这个介于恒星和行星之间的星体。尽管褐矮星和恒星一样常见，而且两者的形成条件几乎相同，褐矮星减少的重量都用于维持内部核聚变反应。因此，褐矮星几乎没有用于维持光亮的能量，它们会渐渐冷却，直至星球寿命的尽头。星球的低温也令它们本身显得暗淡。

 

For years, Kuchner has been fascinated by infrared images of the entire sky captured by NASA’s Wide-field Infrared Survey Explorer (WISE), launched in 2009. The space telescope is specially designed to observe cold objects emitting light at long wavelengths — objects like brown dwarfs. With its initial mission complete, WISE was deactivated in 2011. It was then reactivated in 2013 as NEOWISE, a new mission funded by the NEO Observations Program with a different goal: to search for potentially hazardous near-Earth objects (NEOs).

几年来，Kuchner沉迷于NASA的广域红外线巡天探测器（WISE）拍摄的全天红外图片。WISE于2009年发射，这个空间望远镜是专用于发现宇宙中寒冷的物体在长波长下发射的射线光——比如褐矮星。当最初的任务完成，WISE于2011年被关闭。然后于2013年作为NEOWISE，被NEO监测计划重新启动，新的任务有了一个不一样的目标：发现有潜在危险的近地天体（NEOs）。

 

Previously, Kuchner had focused on stationary objects seen by WISE. But the Backyard Worlds: Planet 9 project shows the WISE and NEOWISE data in a way custom-tailored for finding fast-moving objects. His team layers many images of the same location to create a single, comprehensive snapshot. These are then combined with several similarly “co-added” pictures to form flipbooks that show motion over time.

近期，Kuchner的目标是WISE拍摄到的静止的星体。但是“后院世界：行星9号”计划里WISE以及NEOWISE的数据是为寻找移动物体量身定制的。他的团队将同一个位置的图片进行分层，以创建一个单一而全面的快照。然后将几张相似的快照合并为翻页书，以此来显示随着时间移动的物体。

 

 

Anyone with internet access can scour these flipbooks and click on anomalies. If they would like to call the science team’s attention to an object they found, they can submit a report to the researchers or share their insights on a public forum. Kuchner and his colleagues then follow up the best candidates using ground-based telescopes to glean more information.

任何人都能观看这些翻页书然后点出移动的点。如果想让科学家团队关注一个被发现的物体，只需要向研究人员提交一份报告或在论坛上分享这个发现。Kuchner以及他的同事们会用地面望远镜确认最有可能的星体，以获得星体的更多信息。

 

According to Backyard Worlds: Planet 9 citizen scientist Dan Caselden, participants are free to dig as deep into the results as they choose. A security researcher by trade, Caselden developed a series of tools allowing fellow participants to streamline their searches and visualize their results, as well as aggregate various user statistics. He also helped identify several of the additional brown dwarf candidates while the first discovery was being confirmed.

据“后院世界：行星9号”的公民科学家Dan Caselden介绍，该计划鼓励参与者为他们发现的星体进行尽可能多的深入调查。作为一名网络安全研究员，Caselden开发了一系列工具，让参与者们简化他们的搜索工作，对他们的搜索结果做出更直观的展示，集合众多用户的数据。他也同时鉴定了几颗未被发现的褐矮星，现在，他发现的第一颗褐矮星已经得到了确认。

 

Kuchner and his co-author, Adam Schneider of Arizona State University, Tempe, agree WISEA J110125.95+540052.8 is an exciting discovery for several reasons. “What’s special about this object — besides the way it was discovered — is that it’s unusually faint,” Schneider said. “That means our citizen scientists are probing much deeper than anyone has before.”

Kuchner和他的合作作者，亚利桑那大学的Adam Schneider认为WISEA J110125.95+540052.8是一项令人兴奋的发现，这有几个原因。“这颗星体很特别——除了它被发现的方式之外——这颗星体可以说是极端虚弱而暗淡的，”Schneider说，“这说明我们的公民科学家们的探索比以往深入更多。”

 

 

While computers efficiently sift through deluges of data, they can also get lost in details that human eyes and brains easily disregard as irrelevant.

当电脑从数据的洪流中做出高效筛选的同时，它们有可能错过了一些在人类眼中也被当做无关紧要而无视的信息。

 

However, mining this information is extremely arduous for a single scientist or even a small group of researchers. That’s precisely why collaborating with an enthusiastic public is so effective — many eyes catch details that one pair alone could miss.

无论如何，于这些信息中挖掘，对于单个或是一个小团体的研究人员来说是极端困难的。这就恰恰说明为什么与热心公众合作会如此高效——那么多双眼睛看到的，一个人很可能错过。

 

While Kuchner is delighted by this early discovery, his ultimate goal for Backyard Worlds: Planet 9 is to find the smallest and coldest brown dwarfs, called Y dwarfs.  Some of these Y dwarfs many even be lurking closer to us than Proxima Centauri, the nearest star to the sun.

当Kuchner为之前发现的褐矮星欣喜的同时，他也没忘了“后院世界：行星9号”的最终目的是去发现最小最冷的褐矮星，它们被称为Y矮星。有的Y矮星可能潜伏在离比邻星还近的地方。

 

Their low temperatures make Y dwarfs extremely dim, according to Adam Burgasser at the University of California San Diego. “They’re so faint that it takes quite a bit of work to pull them from the images, that’s where Kuchner’s project will help immensely,” he said. “Anytime you get a diverse set of people looking at the data, they’ll bring unique perspectives that can lead to unexpected discoveries.”

加利福尼亚大学圣地亚哥分校的Adam Burgasser认为，由于低温，Y矮星极度暗淡。“它们太模糊了，需要费很大功夫才能把它们的图像提取出来，这才是Kuchner的项目最需要帮助的地方。让不同的人来看这些数据照片，它们各自独特的视角能引领出出乎意料的发现。”

 

Kuchner anticipates the Backyard Worlds effort will continue for several more years — allowing more volunteers like Caselden and Castro to contribute.

Kuchner期望“后院世界”的事业能再持续几年——这样才能让更多像Caselden和Castro这样的志愿者贡献他们的努力。

 

As Castro put it: “I am not a professional. I’m just an amateur astronomer appreciating the night sky. If I see something odd, I’ll admire and enjoy it.”

就如Castro所说的：“我不是一个专业人士。我只是一个欣赏着夜空的天文爱好者。如果我看到了不寻常的东西，我会赞美它，享受它。”

 

Backyard Worlds: Planet 9 is a collaboration between NASA, UC Berkeley, the American Museum of Natural History in New York, Arizona State University, the Space Telescope Science Institute in Baltimore and Zooniverse, a collaboration of scientists, software developers and educators who collectively develop and manage citizen science projects on the internet.

“后院世界：行星9号”由NASA，加州大学伯克利分校，美国纽约自然历史博物馆，亚利桑那大学，巴尔的摩太空望远镜科学研究所，以及宇宙动物园项目合作。这是一项由科学家，软件开发者以及教育人士合作开发以及管理的，面向国际的公民科学项目。

 

NASA’s Jet Propulsion Laboratory in Pasadena, California, manages the NEOWISE mission for NASA’s Planetary Defense Coordination Office within the Science Mission Directorate in Washington. The Space Dynamics Laboratory in Logan, Utah, built the science instrument. Ball Aerospace & Technologies Corp. of Boulder, Colorado, built the spacecraft. Science operations and data processing take place at the Infrared Processing and Analysis Center at Caltech in Pasadena. Caltech manages JPL for NASA.

NASA于帕莎迪纳市的喷射推进实验室为华盛顿科学任务中心的行星防御协调办公室管理NEOWISE任务。科学设备由犹他州洛根市的空间动力学实验室建造。飞行器由科罗拉多州博尔德城的Ball航空技术公司建造。科学操作和数据处理在帕萨迪纳加州理工大学的红外加工和分析中心进行。加州理工学院为NASA管理JPL。

 

 

Banner image: This illustration shows a close-up view of a Y dwarf. Objects like this, drifting just beyond our solar system, have been imaged by NASA’s Wide-field Infrared Survey Explorer and could be discovered by Backyard Worlds: Planet 9. Credit: NASA/JPL-Caltech

标题图片：这张概念图上是Y矮星的特写镜头。像这样的星体，就在我们太阳系之外漂流，曾被NASA的广域红外线巡天探测器（WISE）拍摄到，也可以在“后院世界：行星9号”中发现。