Named only by police as Lilly, she was discovered in the Duffryn Park area of Blaina on Monday night.
She had been reported missing and was last seen wearing a long black dress in the town's high street around 6.50pm on Saturday.
Blaina is in the South Wales valleys, about 18 miles north of Cardiff.
Detective Chief Inspector Steven Thomas said: "We understand that this will cause distress and concern amongst our communities.
"We have a large police presence in the area at this time as enquiries are ongoing to establish the circumstances of the death. Our officers are here and available for you to speak to."
Anyone with information can call Gwent Police on 101, direct message the force on Facebook or X, or contact Crimestoppers anonymously on 0800 555 111.
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Mr Musk became the world's first trillionaire, and is likely to have been the wealthiest person ever, when SpaceX made its debut on the New York Stock Exchange earlier this month.
By the end of the first day of trading, the SpaceX share price had soared from $150 to $161, making it the sixth-largest US company with a market value above $2.1trn.
That pushed Mr Musk's net worth to an estimated $1.1trn, according to Forbes.
But less than two weeks on from SpaceX's impressive start, its share prices have slumped amid a wider tech stock sell-off - wiping more than $350bn off Musk's fortune, Forbes reports.
The businessman holds a roughly 38% stake in SpaceX, with 4.8 billion shares and 350 million stock options.
As the Nasdaq opened on Tuesday, the aerospace manufacturer and communications company's share price was at $151.90, down more than 16%.
More than $600 billion was wiped off the company's market value over the past three sessions.
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A sharp selloff in the previous session - driven by doubts over debt-funded AI spending - rocked US tech heavyweights including Nvida, Tesla and Oracle.
SpaceX announced earlier this week that it plans to raise money through a bond offering, partly to fund AI development.
Ipek Ozkardeskaya, senior market analyst at Swissquote Bank, said SpaceX "jumping on the bond train to fund excessive AI and infrastructure spending revives earlier concerns that Big Tech may be spending too much on AI infrastructure and increasingly financing that spending through debt".
Nigel Green, chief executive of investment adviser deVere Group, explained: "The AI trade became one of the most crowded trades in global markets.
"When everybody owns the same stocks, the exit door becomes very small very quickly."
Aria died after a knife wound to her chest at her home in Weston-super-Mare, Somerset, in December last year.
The 16-year-old defendant, who cannot be named due to his age, denies charges of murder and manslaughter in relation to her death.
Mrs Justice O'Farrell sent the jury to deliberate on Tuesday afternoon, telling them: "It is a tragic and shocking case and, as I have said before, it gives rise to very strong feelings.
"It is important to put your empathy to one side and judge the evidence fairly, without being swayed by an emotional reaction.
"You should carefully consider all the evidence that has been put before you"
The prosecution's case is that the boy stabbed Aria deliberately, intending to kill her or cause her really serious harm, the judge said.
The prosecution claims his action was one that any reasonable person would realise was bound to put Aria at risk of physical harm.
The judge said the boy "accepts he stabbed Aria with the kitchen knife but he says it was an accident".
"His intention was to scare her," she continued. "He held the knife in his hand and lurched or jabbed towards her.
"He didn't intend to kill her and did not intend to cause her really serious injury."
The jurors have been urged to reach a unanimous verdict.
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During the trial, the court heard the boy walked to a nearby train station after Aria was injured, and told a group of children he had killed her accidentally.
Another child rang 999 and police officers attended the station, arresting the boy shortly after he boarded a train.
A Home Office pathologist told the court Aria died as a result of a single stab wound to her chest.
The nine-year-old had been at school and a dance class on the day of her death. She was collected by her mother, Tori Hull, at about 4.30pm.
After they went shopping and returned home, Ms Hull left for an evening work shift and left Aria watching YouTube videos on the television.
A family friend, who was staying at the house temporarily, found Aria lying on the living room when he returned at about 6pm.
Police and paramedics arrived a short time later but Aria could not be saved and was pronounced dead at 6.58pm.
Turner Prize winner Helen Cammock's 40-minute video work titled Persistence made a reference to "the wilful starvation of the Indian population by Winston Churchill".
In the work, narrated by Cammock, she examined Oliver Cromwell's 17th century military campaigns in Ireland, and said he had "starved people, en masse", which was "a little like" Churchill in the Bengal famine.
The artwork prompted Churchill biographer Lord Andrew Roberts to pen an open letter - signed by more than 50 peers including Churchill's grandson Sir Nicholas Soames - refuting the claims.
Other signatories include Michael Grade and Zac Goldsmith.
Three million people in east India have been estimated to have died in the Bengal famine of 1943.
Churchill's policies as prime minister at the time have been criticised by some for exacerbating the situation.
Lord Roberts of Belgravia argued the installation's description of Churchill was a "bare-faced lie" and "ideologically motivated rant" that "denigrated" the war-time prime minister.
"The Bengal famine was an unimaginable tragedy and disaster, but the accusation that it was deliberately visited upon the Bengalis by Churchill is foul and vile," he said.
"It is also historically ludicrous, as every serious historian of the period attests."
Lord Roberts said the Bengal famine was caused by a typhoon and that Churchill told his war cabinet every effort must be made to help those affected and asked international leaders to send in grain.
Following the backlash, Cammock said she made the decision to "withdraw" the work from the gallery.
"There is an incredible pressure on artists and arts institutions to bend to external pressure; to be benign at best and silent at worst. I do not accept this pressure," she said.
"To question, challenge and explore ideas and histories is vital to a healthy society and art is intrinsic to this.
"For me, art is about dialogue, it is about a questioning of existence through the transformation and translation of thoughts and ideas.
"It asks us to think, to feel, to react - and we must take responsibility for our own reactions to it."
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She said her work "asks us to think about who is honoured and valorised and who is not; whose stories are told and whose are not".
She added: "Persistence will have its own life after this: it won't hide and it won't be afraid to speak with those who are prepared to sit with it and listen - not agree or submit to it - but to hear it out, consider its points and make their own minds up."
In a statement, the gallery said: "Helen Cammock has decided to remove her film, Persistence, from display at the National Portrait Gallery.
"We respect her decision, just as we acknowledge the opinions of those who were offended by what was said in the film."
The gallery added: "The aim of this project was to give artists the opportunity to create works as personal and creative responses to our collection. The work was presented as an artistic piece, not a documentary, and the views expressed in the film do not necessarily reflect those of the NPG."
Lord Roberts said Cammock "should be commended for doing the honourable thing and putting historical truth over her artistic licence".
Some outlets previously said they received ransom notes about the case in the days following the disappearance of Ms Guthrie from her home near Tucson, Arizona.
Two notes sent to a TV network in the wake of the 84-year-old's disappearance were believed to be potentially credible by investigators.
The first note said Ms Guthrie, the mother of Today host Savannah, was safe and demanded cryptocurrency in exchange for her release, whereas the second did not ask for money and was said to be very different from the first.
Now Sky's US partner network NBC News has reported that this second note indicated she had died after her disappearance.
However, it did not offer an apology or ask payment for the release of her body, according to NBC.
According to the note, those who kidnapped her did not mean to kill her, but she died shortly after being taken.
The existence of the note was known, but some details including claims she had died, had not previously been released.
Tucson TV station KOLD that received two notes agreed to hold off sharing the contents publicly so any future communications with the kidnapper or kidnappers could be authenticated.
Jessica Bobula, news director of KOLD, said the station received several notes after Ms Guthrie disappeared and the station told authorities and shared only what the FBI released about the correspondence.
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Ms Guthrie was reported missing from her home on 1 February and was last seen at the property at around 9.45pm the previous evening.
Police believe she was kidnapped or "otherwise taken against her will" after finding blood near her front doorstep.
The FBI released surveillance videos of a masked man outside Guthrie's front door on the night she went missing. It has since described the man as a suspect.
Volunteers and search teams scoured the nearby desert terrain filled with cactuses, bushes and boulders in the weeks after she vanished.
A volunteer group recently conducted a search for her body near the Arizona-Mexico border but didn't report finding her.
Investigators involved in the case examined the two notes following Ms Guthrie's disappearance and believe they could be credible.
After the second note was sent, Savannah Guthrie spoke about her mother's possible kidnapping in an Instagram video, and said the family would "pay" for her return.
"We received your message and we understand," Savannah Guthrie said, sat beside her brother, Camron, and sister, Annie. "We beg you now to return our mother to us so that we can celebrate with her. This is the only way we will have peace."
"This is very valuable to us, and we will pay," Savannah Guthrie added.
Her video did not specify the details of the message she received.
The Pima County Sheriff's Department said on Tuesday: "The investigation into the disappearance of Nancy Guthrie remains active and ongoing.
"The Pima County Sheriff's Department continues to work closely with the FBI as investigators follow up on leads, review information, and pursue the facts surrounding this case."
Savannah Guthrie returned to NBC's Today show in April for the first time since her mother's disappearance.
The 54-year-old has said she's a changed person since she went missing and that it's difficult to press ahead without knowing what happened to her.