"The study of one planet found hints of fine silicate-particle clouds. Research on the other planet found no chemical fingerprints for any of the molecules scientists were seeking.
"We had expected this tremendous signature of water ... and it wasn't there"
The question arises why they weren't doing a full search for all detectable molecules.
They're becoming like that kid who's still looking for a pony.
If this nonsensical Impact-Splash scenario had happened 4.4B years ago, a mars directly impacts the earth and slashes out the lunar mass into stable orbit beyond the roche lobe, we as water-rich critters wouldn't even BE here. That event would instantly release 10^31 J of KE, a gamma ray burser like the Shoemaker-Levy comet fragments impacting Jupiter in 1994, only of VASTLY greater magnitude.
What settles out AIN'T delicate molecules like H2O, NH3, etc; more like pyroxenes...this planet would be just as sterile as venus. So astronomy geniuses, how did earth's OCEANS get here as early as 3.9B years ago?