http://tes.asu.edu/dust/p24371-tnight.gif
This, from April 6, shows as much spot variation as can be seen in just about any of the archive images for TES nighttime. Since these images are interpolated from strips of data, its hard to tell if we're dealing with one glitched spot interpolated out to a much bigger feature, or an actual hotspot. An example of the strips -> interpolated map can be seen here:

If you watch the nighttime movie (warning, 45 meg file) over the course of the last 5 years, there doesn't appear (to my amateur eyes) to be any variation similar to this. There doesn't appear to be any variation in the daytime or atmospheric maps on this day or afterwords, nor is there any major variation in the next nighttime image either. Could this be geologic activity (or would there be residual heat the next day?) or an impact event?

The one-off nature of the data makes me think it's a glitch, but I'm no expert.

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Everything I need to know I learned through Googling.

I vote glitch. If there hasn't been any evidence of the spot for five years and it suddenly appeared I can't think of any areological (aka geo but we're on Mars) process that would appear so quickly. Especially when the planet is thought to be larglely inactive in that respect.

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Yes, I have a life. It's quite different from yours.

Don't think a glitch, since that would cover a pixel usually.

Could it be clouds? (since an area covered with clouds would temper the night temperatures)

It's a launch signature!

Prepare the bioweapons!

When they land, throw every flu and cold sufferer we have at them!

It's got beams comming of it.... Looks like a lensflare......

OMG it's Planet X

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http://boinc.mundayweb.com/one/stats...630/prj:6/.png

Look at the scale at the bottom - red "hot" on the 6 April image is - 55 c NOT +15c seen in the daytime images. It may still be anomalous.

From Dr. Tim Titus, of the USGS:

The star shaped hot spot you see in the TES night image is an artifact of some bad data. It looks like a possible calibration error as only a few data
points have the anomalous hot temperature. And they are preceded by several data points at 3 Kelvin (the temperature of deep space).

I'm pretty impressed that you kept looking and found this for yourself! =D>

As opposed to seeing something odd, making obtuse and extraordinary claims about it and assuming its fact? There's enough of that going on already [-X

Precisely. 8)