So, life on Mars...

[Ryujin]

Says the bad guy in almost every scifi horror movie.

"Hold on a minute, Wayland-Yutani!"

 

[cranberry]

Hopefully, it isn't the result of cross contamination.

 

[Whizbang Dustyboots]

I think the most important question regarding an ancient Martian life is whether it has the same DNA as Earth life. if so, that essentially proves panspermia. I imagine who seeded who (or if there was a third party) would be long debated.

Let's be honest: It's almost certainly Elon Musk.

 

[Reynard]

Let's be honest: It's almost certainly Elon Musk.

I was waiting for this thread to intertwine itself with the time travel one...

 

[Desdichado]

Should I queue up DJ Wag & MR, or Pulsedriver & Rocco, or old school David Bowie?

 

[Umbran]

I think the most important question regarding an ancient Martian life is whether it has the same DNA as Earth life. if so, that essentially proves panspermia.

No it doesn't.
The building blocks of DNA are commonly available throughout the cosmos. Having two independent sources use them would not be implausible.

 

[Umbran]

Let's be honest: It's almost certainly Elon Musk.

He might count as contamination, yeah...

 

[Reynard]

No it doesn't.
The building blocks of DNA are commonly available throughout the cosmos. Having two independent sources use them would not be implausible.

The way our DNA makes base pairs is not particularly special. It would be astoundingly unlikely that two independently evolved forms of life would have the same base pair system. Even the component molecules are not the only ones that can be used to form DNA.

 

[The Firebird]

No it doesn't.
The building blocks of DNA are commonly available throughout the cosmos. Having two independent sources use them would not be implausible.

The way our DNA makes base pairs is not particularly special. It would be astoundingly unlikely that two independently evolved forms of life would have the same base pair system. Even the component molecules are not the only ones that can be used to form DNA.

An interesting note: the existence of the nucleobases may not get you far because it is quite difficult to react nucleobases with ribose (RNA; probably you get that first). One of the big discoveries in this field found ways to bypass the free nucleobases and instead uses an intermediate that has components of both sugar and nucleobase. Adding in the noncanonical nucleobases, it is hard to know what to look for.

I don’t think this discovery is going to yield DNA. It’s potential evidence of life, not organic material.

“The reason, however, that we cannot claim this is more than a potential biosignature is that there are chemical processes that can cause similar reactions in the absence of biology, and we cannot rule those processes out completely on the basis of rover data alone.”

It’s some non-organic mineral markers, if I understand it correctly.

There is also organic material. From the paper:

"The presence of organic matter in Bright Angel formation mudstone (Fig. 3d), which could have been produced on Mars through abiotic synthesis suggests that such reactions could have occurred. Further analysis is required to determine whether the specific organic compounds present in the Bright Angel formation can drive the reduction of mineral-hosted sedimentary Fe3+ at low temperature."

 

[aco175]