I posted this here because I'm sure the answer lies somewhere in the EU. What did the Empire say about the destruction of Alderaan? Was it known by the general population that the Death Star destroyed it? Since the Rebels destroyed the Death Star, I doubt they would have kept quiet about it. They would have figured a way to get the word out even though I'm sure the Empire controlled the media. So is it written anywhere how the population found out about what happened, how they reacted?
Most joined the Rebellion. Some still supported the Empire in a boomerang bigot kind of way. Some accepted Palpatine's offer for a new homeworld - on Byss. It didn't end well.
But did the Empire ever admit that they were responsible for it's destruction? I now remember that there was something saying that they gave a vague excuse about a planetary disaster(?) and expressed their "sympathies". Though, I'm not sure about this. It was a decade ago that I heard this rumor.
The Empire admit responsibility? You really should know the answer to that one. Two guesses: and if you say yes, you are wrong. The Empire said the Rebellion was responsible, but most didn't buy it. For one, the Rebellion had no reason to destroy one of its most supportive planets. Also, how on earth would they do so? And third, the Empire wasn't exactly well-loved by the time Alderaan was destroyed. The Senate had to be disbanded, after all, because it was a hotbed of dissent. I'm pretty sure whatever the excuse, most didn't buy it.
The old HoloNet entries of the Adventure Journal have some information on the immediate response: 35:3:12 (Day of the destruction): Alderaan destroyed by own superweapon Basically says it all: The Imperial navy investigates the destruction site and comes to the conclusion, that Alderaan has been secretely destroyed several superweapons underground. One of them presumable misfired. Also, the region is closed of and rumors of a 'rouge planetoid' appear. Palpatine makes a public appearance and ivites Alderaanians to Byss. (Imperial Holovision) 35:4:22: Tarkin and staff die in shuttle crash The official cover-up story for Tarkin, Motti and Tagge. Died in an accident when approaching teh Tallaan shipyards. (NewOrder Progressive) 35:8:4: Alderaan destroyed by Imperial Terror Weapon First Transmission of the AEN. Claims that the Empire destroyed Alderaan and includes a holotape from Delaya that recorded the destruction. Also included messages between Alderaan and Delaya prior destruction and a message from Ars Drangor to the Grand Moffs that references the Death Star. The article also states that Tarkin died over Yavin. (Alderaan Expatriate Network) 35:8:22: Navy reports Super-Weapon destroyed Alderaan The Navy officially admits that the Death Star destroyed Alderaan to prevent Bail Organa's biowar program to complete and spread throughout the galaxy. Current location of the Death Star is 'classified', although rumors report it was destroyed in the outer rim. (Imperial Holovision) So, initially the Empire claimed Alderaan was destroyed by its own superweapon, and I'm sure many people loyal to the Emperor believed this. While truth was published later, keep in mind that this was via an illegal holonode, so not everyone in the population had access to it. While the Empire finally turned around and admitted the involvement of the Death Star, it still claimed it was to protect the galaxy from a massive bio-weapon threat.
I think its one or two things. If the Death Star would not have been destroyed shortly there-after by the Rebellion - the Imperials/Emperor/Tarkin would have [note: not ADMITTED] stated that they did it. Tarkin even said the purpose was to sow fear in neighboring systems that harbored the idea of joining/aiding the Rebellion. But; I think once the D* was pretty much immediately destroyed like a week later... its basically "well... we can't really continue through just fear... so lets propaganda this crap."