April fool? No foolin’...

April 4, 2011 By Tammy Plotner
Mariner 10. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington. And also thanks to H. Levenson!

If you fell victim to an April Fool’s prank, then consider that life can play some of the most ironic jokes of all. On April 1, 2011 the Mercury MESSENGER was taking some of its first images from Mercury’s orbit when it accidentally captured the totally unexpected… the ancient Mariner 10.

According to the NASA Press Release, the first reaction of some on the MESSENGER team was that the feature to the left of Mercury’s limb must be an imaging artifact. “It’s the effect of solar neutrinos on the WAC’s CCD,” pronounced Project Scientist Mack Knott. The imaging team was skeptical of this explanation, however, and all Knott could add was “I could explain it to you, but you’d have to understand Feynman diagrams.”

The imaging team brought the anomalous image to the attention of Mission Systems Engineer E. Finn Again, who immediately called an emergency gathering of the Collision Avoidance Review Board. Fortunately, the unusual object in the image did not appear to be in the immediate path of MESSENGER’s next few orbits, but the fact that earlier and subsequent images of the same scene did not include the object prevented a determination of its trajectory.

One of MESSENGER’s Science Team members, Prof. S. T. Rom, recognized the object immediately as Mariner 10, the only spacecraft before MESSENGER to have visited Mercury. Launched in 1973, Mariner 10 flew by Mercury three times in 1974 and 1975 before communication with the probe was lost. Prof. Rom is the only member of the MESSENGER team to have served on the science team of Mariner 10 as well.

The Science Operations Center was filled at the time with MESSENGER team members, and everyone proceeded at once to theorize on why Mariner 10 might appear in an MDIS image of Mercury. Mission design lead Mick Adams quickly calculated that Mariner 10 should not be encountering Mercury on this date. “Mariner 10 and Mercury were in a resonant state that brought the spacecraft by the planet once every two Mercury years. By my calculation, this appearance is 23 days early.”

Guidance and control lead E. C. Shaughn offered that the effect of solar radiation should have substantially altered Mariner 10’s orbit over the past 36 years as a result of solar sailing. Propulsion lead Brecht Engel added that some residual propellant after Mariner 10’s last propulsive maneuver may have outgassed, and that multiple outgassing events may also have contributed to trajectory changes.

MESSENGER’s navigation team members, all of whom are named Williams, plugged these suggestions into their codes. Minutes later they were able to announce to all assembled that Mariner 10 appeared to be in a new resonant state, one synchronous with Earth’s period. The ancient spacecraft is locked into an orbit that swings it by once every Earth year, on April 1st.

There’s no joke like a cosmic one!

Explore further: MESSENGER Returns Images from Oct. 6 Mercury Fly-By

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5 / 5 (1) Apr 04, 2011
whoa! that's awesome. what a coincidence. amazing. still, this is sort of hard to believe, it's like finding a needle not in haystack but in an ocean of haystacks. what are the odds that messenger actually gets this particular image. this is insane.
5 / 5 (3) Apr 04, 2011
That could be photoshopped in a few minutes.

This really IS an April Fools joke, and you bought it buddy!
not rated yet Apr 04, 2011
Professor Rom suggested that Mariner 10 may have remained in place as of the time of its last signal:

Day after day, day after day,
We stuck, nor breath nor motion;
As idle as a painted ship
Upon a painted ocean.

The dead albatross hanging from Roms neck, however, reduced the effectiveness of his argument.

not rated yet Apr 04, 2011
Even if it proves a hoax its amazing to think of it in such complexity..mwofredbay
5 / 5 (1) Apr 05, 2011
If NASA needs more publicity they should put an obelisk or some kind of alien artifact in the photo, this is just too mundane. Also it should be just blurry enough to get a good argument going.
1 / 5 (1) Apr 05, 2011
If NASA needs more publicity they should put an obelisk or some kind of alien artifact in the photo, this is just too mundane. Also it should be just blurry enough to get a good argument going.
Scan the planet's surface. Did you notice the doodled crater, which almost appears to be a face? Or, the mysterious dark spot (landing craft shadow?)? And, then there's the vague, structure - which looks sort of like an airplane silohuette. And, I also see a bust of Albert Einstein photoshopped into the terrain (there's a telltale seam to the left of the image).

There's an obvious seam in space, but I don't see anything on Mariner 10.

Did I miss anything?
not rated yet Apr 08, 2011
if its a joke its not put together in a very funny way.
you dont make reference to April fools etc, and the names need to be funny.
not rated yet Apr 08, 2011
This looks 'shopped. I can tell from some of the pixels, and seeing quite a few shops in my day....

also the resemblance to the 1973 promotional photo is uncanny...

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