As it happened: Experts trolled online during UFO sightings meeting

Thank you for following our coverage of today's public meeting on NASA's probe into unexplained anomalous phenomena - the first by the US space agency.

If you missed the event today, you can catch up on all the key updates by scrolling through our blog below.

The 16-member panel of experts have been tasked with identifying what data can be analysed to shed light on unidentified anomalous phenomena (UAPs).

Following today's public meeting, the team, led by astrophysicist David Spergel, are now required to put together a full report setting out how UAPs can be studied going forward using data, technology and the tools of science.

The aim of the report is to inform NASA on what data can be collected to shed light on the phenomena.

It won't include analysis of any previous UAP incidents, the space agency has said.

When it is ready, the full report will be released to the public and will be followed by a meeting to discuss its findings.

A lot of ground was covered today in NASA's first public meeting on its study of UFOs - or rather, unidentified anomalous phenomena (UAPs).

The independent panel of 16 experts discussed a wide range of issues in the four-hour long televised meeting at NASA HQ in Washington.

With a report not due until later this year, there's still a long way to go to find out if scientists can reach any solid conclusions around the phenomena. But what did we learn today? Here's a quick recap: 

• The panel is looking at what unclassified information is available on the subject and how much more is needed to understand what is going on in the sky above us;
• Experts will also discuss what role NASA can play in assisting efforts to understand UAPs;
• We learned from chair David Spergel that current data collection around UAPs is "unsystematic and fragmented", with his conclusion after the hours-long meeting: "We need better data";
• The US Department of Defence's All-domain Anomaly Resolution Office - which also investigating UAPs separately to NASA - has received around 800 sightings so far, but only a tiny fraction of those contain signals which could be deemed "anomalous";
• Another panel member, astrobiologist David Grinspoon, said NASA's search for life beyond earth could play a role by supporting the study into UAPs;
• Panellists have received online harassment and abuse since signing up to take part in the study - including during today's meeting - we were told, but NASA has emphasised its "complete and total support" for the team;
• A final report is expected by the end of July.

The post-meeting conference with some of the expert UAP panellists has now ended.

The UK Space Agency will not be be involved in the study of unidentified anomalous phenomena (UAPs) alongside NASA.

Responding to a question over whether he would lead a joint collaboration between the two agencies, panel member Daniel Evans - a dual UK and US national - said no such discussion had taken place.

In another question, the panel is asked why they use of the term UAP.

Responding to this, one expert says the term is used in an effort to be "unbiased" and to be "objective".

He says calling objects in the sky UAPS "removes the bias".

UAPs, or unidentified aerial phenomena, are usually considered to be unexplained sights in the sky, such as balls of light, rather than flying objects. 

UFOs, or unidentified flying objects, refer to exactly that. 

Daniel Evans says the independent study panellists have continued to receive online abuse during the first meeting of the panel today.

He is addressing a question about the abuse experts have experienced since signing up to take part in the UAP study.

"If you were watching the NASA YouTube feed this afternoon and looking at the live chat that's on the side... you can see some of the online trolling. That's really just the tip of the iceberg", Mr Evans says. 

Online harassment "only serves to detract" from the process and all panellists have NASA's "complete and total support", he adds.

"This is hard work, it's serious work. If we are truly to respect the sanctity of the scientific process then we need to allow science indeed to be free, and that freedom stems directly from an absence of harassment."

Daniel Evans says there is a stigma attached to the term "UFOs" (unidentified flying objects) when referring to sightings of unexplainable events in the sky.

Responding to a question over why the term unidentified anomalous phenomena (UAPs) is instead used, Mr Evans says "this is a serious business".

"Many experts have told us about the potential risks to US airspace safety... we want to employ a rigorous scientific method."

He said it's "very rewarding" that NASA is involved in the subject which has "not historically been in its remit".

Mr Evans says the sensitivity and stigma around UAP study means it is "difficult to find individuals willing to participate" - but noted that none of the panel experts turned the invite down.

Panel chair David Spergel and Daniel Evans, assistant deputy associate administrator for research at NASA's science mission directorate, are now holding a post-meeting teleconference with members of the media.

The pair are giving an overview of today's session to participants before a Q&A session begins.

The meeting with the panel of experts has now come to an end.