Categories: sun

I Thought I Saw A UFO! Mystery Triangle On STEREO Image Explained…

Mystery diamond-shape “object” entering the field-of-view of the HI2 telescope on STEREO Behind around December 26, 2011. Credit: NASA

The STEREO (Solar TErrestrial RElations Observatory) is a two-year mission conducted by NASA. It employs nearly identical twin telescopes – one positioned ahead of Earth’s orbit and the other behind – designed to study the Sun’s activities spectroscopically. However, it can sometimes pick up some very unusual findings! On December 26, 2011, the STEREO Behind Observatory’s HI2 telescope captured an ambiguous triangle entering the field of view and moving from right to left just above the trapezoidal occulter as seen in the above movie. Just what is this “thing”?!

Before you get ready to call the men in black, know that there is a logical answer… and it comes into play on the opposite side of the STEREO image. Play the movie again and watch. (It’s a bit more obvious in this close-up view.) Just as the weird triangle begins its approach, you’ll notice the dazzling Venus enters the field of view of the HI2-B at the same time to the lower left. As you watch, you’ll see they keep exactly the same time – in opposite – across the detector image. This isn’t just a chance happening… it’s a naturally-occurring internal reflection caused by Venus’ brilliance in the telescope’s optics. It might be exciting for the moment, but it’s nothing that hasn’t happened in the past. Just check out these great STEREO Reflections of Earth, and all sorts of other cool images on the STEREO Image Artifacts pages.

[/caption]

What else can be seen? As you can tell from this photograph, Earth is also starring in the show, but doesn’t come in as striking as Venus. What’s more you can also see the tail of Comet Lovejoy streaking in from the left just above Venus towards the end of the movie.

Exactly how do you keep track of what’s going on? Check out the Where Is STEREO? pages for up-to-date information and the totally cool Current STEREO Solar Images!

Original Story Source: Triangular shaped object in STEREO data explained.

Tammy Plotner

Tammy was a professional astronomy author, President Emeritus of Warren Rupp Observatory and retired Astronomical League Executive Secretary. She’s received a vast number of astronomy achievement and observing awards, including the Great Lakes Astronomy Achievement Award, RG Wright Service Award and the first woman astronomer to achieve Comet Hunter's Gold Status. (Tammy passed away in early 2015... she will be missed)

Recent Posts

Juno Reveals a Giant Lava Lake on Io

NASA's Juno spacecraft came within 1,500 km (930 miles) of the surface of Jupiter’s moon…

18 hours ago

What’s the Most Effective Way to Explore our Nearest Stars?

It was 1903 that the Wright brothers made the first successful self-propelled flight. Launching themselves…

1 day ago

Radiating Exoplanet Discovered in “Perfect Tidal Storm”

Can tidal forces cause an exoplanet’s surface to radiate heat? This is what a recent…

1 day ago

The Giant Planets Migrated Between 60-100 Million Years After the Solar System Formed

Untangling what happened in our Solar System tens or hundreds of millions of years ago…

2 days ago

Artemis Astronauts Will Deploy New Seismometers on the Moon

Back in the 1960s and 1970s, Apollo astronauts set up a collection of lunar seismometers…

3 days ago

Ice Deposits on Ceres Might Only Be a Few Thousand Years Old

The dwarf planet Ceres has some permanently dark craters that hold ice. Astronomers thought the…

3 days ago