Chances are you’ll be questioning how a topic goes from being one in every of hundreds of topics within the Planet Hunters NGTS challenge to changing into a candidate after which, hopefully, a bonafide planet! On this sequence of posts I hope to shed some mild on the life cycle of a Planet Hunters NGTS topic.
As soon as a set of topics are “retired” from the location, which happens when all the topics have acquired responses from a minimum of 20 distinctive customers, the info is collected from an enormous “csv” file (that stands for comma-separated values). This comprises each response by each volunteer for each topic included within the challenge and is successfully a large spreadsheet, albeit one with hundreds of thousands of rows that will crash any normal spreadsheet viewer like Excel. This enormous file is processed by a pc program and an important information is pulled out and inputted into a big database that kinds the hub of our operation.
From right here, I can run one other program that iteratively calculates scores for every topic for every potential response and computes weights for every person in order that we will pay extra consideration to the classifications that establish transits extra simply and subsequently pick topics with excessive scores that may have been missed with easy vote counting. That is much like the scoring and weighting schemes used within the Planet Hunters and Planet Hunters TESS initiatives, in addition to many different citizen science initiatives. This lets me generate a listing of essentially the most promising candidates (e.g. topics which can be most likely U-shaped) that are what you’ll see within the Secondary Eclipse & Odd/Even Transit Checks. I can then apply the same program to classifications in these workflows to establish the topics which can be more than likely to not have secondary eclipses or transit depth variations. These are the strongest candidates for being planetary transits as an alternative of eclipsing binaries.
The subsequent step is essentially the most arduous as I look by all these candidates by eye (and there’s normally a number of them!) and pick essentially the most promising ones to get a second opinion on. Crammed with optimism and with candidates in hand, I present these to the NGTS crew who consider them as a bunch to pick essentially the most promising planet candidates that we expect are worthy of additional investigation. At this level we’d class these objects as potential planet candidates, though they are often dominated in or out by a sequence of checks utilizing completely different information sources that I’ll go into in later weblog posts.
