Challenge
| Subject: | The Case of the Super Moon | ↰ |
| Difficulty: | ●●●○○ | |
| Duration: | 20 minutes (estimated) | |
A supermoon is when a full moon coincides with the perigee (closest point) in the Moon's orbit around the Earth. This event can make the moon appear larger and brighter than a typical full moon. Unfortunately, events like this are frequently misrepresented by people who want the credit for taking an amazing photo. Digital alterations and older pictures are commonly portrayed as recent photos. On Twitter, a user posted an amazing photo of the supermoon. This alleges to show a supermoon over ruins in Greece. Users uploaded various versions of this picture to FotoForensics for analysis. The pictures differ in size, quality, and metadata. Here are three examples: Moon #1 Moon #2 Moon #3 Look at these pictures and try to answer the following questions in order to determine the credibility of the tweeted picture:
Look at the metadata. Try using error level analysis. Look at the metadata. There are two dates: when the picture was tweeted and when the picture was taken. Were either of these dates when a supermoon occurred? This requires using a search engine, such as Google or Bing. First identify the ruins. Then look for pictures of the ruins at night. Then see if you can identify the photographer's name. None of these pictures are camera-original. A camera-original photo should have metadata that reflects the camera. Pictures #1 and #3 have minimal metadata that does not identify any camera information. Picture #2 identifies the picture as coming from a Canon EOS 5D camera. However, the metadata also identifies Adobe Photoshop CS2 for Windows and a "Derived From Document ID", indicating that this picture is based on another picture. Pictures #1 and #3 have undergone multiple resaves. ELA shows a flat
background, where the low quality has removed most of the noise from the
picture. Picture #2 shows a some rainbowing and very strong high contrast edges. These are consistent with the use of an Adobe product; Adobe automatically sharpens high contrast edges when JPEGs are saved. The metadata in picture #2 contains a timestamp: 2010-06-27 01:19:53. Although the tweet says it was taken "yesterday" (meaning 2015-06-24), it was actually taken move than five years earlier. The picture was tweeted on 2015-06-25 and the metadata from picture #2 says it was taken on 2010-06-27 around 1:19 am. (The date could actually be 2010-06-26, depending on the timezone.) A full moon supermoon occurs about once every 13 months. A list of previous supermoons can be found online. The date for the 2015 supermoon is September 28, not June 25. And in 2010, it was January 30, not June 27. We can also identify that there was no full moon within three weeks of 2015-06-25. On 2015-06-25, only half of the moon should have been visible. In contrast, there was a full moon on 2010-06-26, so the picture is consistent with the metadata. While the picture does represent a full moon, it is not a supermoon. Moreover, it was not taken on the date that was claimed by @BestWorldPix on Twitter. A search on Google for pictures of ruins in Greece identifies this location as a temple of Poseidon in Attica, Greece. A search for temple of Poseidon in Greece at night identifies a series of related photos captured by photographer Anthony Ayiomamitis late at night on 26-June-2010. The web page at TWAnight.org states that the Royal Museums Greenwich featured the middle picture in a photo contest. Picture #2 comes from Ayiomamitis' Flickr stream, which is linked from the Museums web site. The Flickr picture has minor color alterations. It is very likely that Ayiomamitis first photographed this picture and digitally enhanced the colors for a photo contest. Years later, @BestWorldPix posted the modified picture to Twitter and misrepresented it as a recent photo of a supermoon. | ||