Neil deGrasse Tyson has been accused of making unwanted sexual advances by two women - one of whom says the popular astrophysicist and TV host was ‘looking for Pluto’ in her dress.

Dr. Katelyn N. Allers, a physics professor at Bucknell University, alleges that Tyson ‘felt her up’ at an after-party following an American Astronomical Society conference in Long Beach, California in 2009.

The after-party was a social function in which astronomers mingled and socialized, according to Patheos.

‘Tyson was there, and he was dancing and drinking and all of that at the party, so a friend and I decided to get pictures with him,’ Allers said.

Neil deGrasse Tyson (seen above on November 8 in New York City) has been accused of making unwanted sexual advances by two women - one of whom says the popular astrophysicist and TV host was ‘looking for Pluto’ in her dress

Allers and Tyson were snapped in two photographs together.

The first photo seems innocent with both Tyson and Allers looking into the camera and smiling.

After that photo was taken, Allers said Tyson began to take keen interest in her tattoo, which depicts the solar system.

The tattoo extends from Allers’ arm to her back and collar bone region.

Allers said: ‘After we had taken the picture, he noticed my tattoo and kind of grabbed me to look at it, and was really obsessed about whether I had Pluto on this tattoo or not… and then he looked for Pluto, and followed the tattoo into my dress.’

Allers said Tyson’s behavior was not severe enough to warrant a complaint about sexual assault.

Still, she said she was shocked to see him capable of ‘creepy behavior.’

‘My experience with him is he’s not someone who has great respect for female bodily autonomy,’ she said.

Four years after the encounter, Allers told a colleague at Bucknell, Dr. Michele Thornley, about what took place.

‘Katelyn described the earlier incident to me in the fall of 2013, after she was invited to attend a dinner with Dr. Tyson when he was to be on campus in spring 2014 as a speaker in Bucknell’s “Tech/no” series,’ Thornley told Patheos.

Dr. Katelyn N. Allers, a physics professor at Bucknell University, alleges that Tyson ‘felt her up’ at an after-party following an American Astronomical Society conference in Long Beach, California in 2009

Allers said Tyson’s behavior was not severe enough to warrant a complaint about sexual assault. Still, she said she was shocked to see him capable of ‘creepy behavior’

‘My experience with him is he’s not someone who has great respect for female bodily autonomy,’ she said

Allers told Thornley that she did not want to attend the dinner.

Thornley says Allers indicated that she also had no desire to go public with the allegations.

Thornley says she also tried to make sure that female students did not meet with Tyson unless there were a group of people around.

Another woman, Ashley Watson, told Patheos that she quit her job as Tyson’s assistant after her boss made inappropriate sexual advances toward her.

She says Tyson invited her to his apartment at 10:30pm one night to ‘share a bottle of wine’ and ‘unwind for a couple of hours.’

Watson, who says she felt pressure to impress her boss, agreed to have a glass of wine.

When she arrived at his apartment, things got awkward.

Tyson, 60, who is a married father of two children, took off his shirt and shoes and walked around in a tank top undershirt, Watson says.

He then put on romantic music.

Watson says Tyson then took out a cutting board and knife to cut cheese for the both of them.

She says that before he started slicing the cheese, he took the knife and made a stabbing gesture toward her, which she took as a ‘bad joke’ that was nonetheless intimidating.

‘It was definitely a very weird power move,” she said

Ashley Watson (above) told Patheos that she quit her job as Tyson's assistant after he allegedly invited her to his apartment and propositioned her for sex

Watson says Tyson continued making suggestive comments that contained sexual innuendos.

He allegedly began talking about human beings needing certain ‘releases.’

Tyson also spoke of the difficulty of being away from home for months at a time.

When Tyson asked Watson if she needed releases, Watson says she told him a story about her being sexually harassed.

Watson says he was unmoved.

‘It was like talking to a wall,’ she says.

As she got up to leave, Tyson stopped her and asked her to engage in a ‘Native American handshake’ in which both of them hold hands tightly, make eye contact, and feel for each other’s pulse, she says.

Tyson told Watson that the handshake was a ‘spirit connection.’

When Watson tried to leave, Tyson said he wanted to hug her and that afterward he would ‘just want more.’

Watson says that at that point she left Tyson’s apartment quickly.

The next day, Watson says, she confronted Tyson. She says she told him that she felt betrayed since she considered him to be a mentor.

Tyson is said to have responded to her by saying that she would never succeed professionally because she was too ‘distracting.’

Watson says she complained to one supervisor about Tyson. She also called a harassment hotline.

In 2014, a former classmate of Tyson’s at the University of Texas in Austin wrote a blog post in which she accused him of rape, which she alleges took place in 1984.

In 2014, Tchiya Amet, a former classmate of Tyson’s at the University of Texas in Austin wrote a blog post in which she accused him of rape, which she alleges took place in 1984

Tchiya Amet, a musician and teacher who studied galactic astronomy in the graduate program, alleged that Tyson drugged and raped her.

‘He offered me a glass of water,’ she wrote in 2014.

‘I accepted a liquid in a cup made out of a coconut shell.

‘I recall coming back to consciousness briefly, then next thing I remember is seeing him in the hallway the next day.

‘I have lived in this nightmare for 30 years, and it stops today.’

Watson says she reached out to Amet to express her support.

‘I just wanted to reach out [and] say that Neil deGrasse Tyson...tried to seduce me into having sex with him and it was super messed up and I had to quit my job,’ Watson wrote to Amet.

Watson told Amet she was worried that Tyson would try to do the same to other women.

Fox and National Geographic, the television entities behind deGrasse's popular series Cosmos: A Spacetime Odyssey, told The Hollywood Reporter that they are investigating.

'We have only just become aware of the recent allegations regarding Neil deGrasse Tyson. We take these matters very seriously and we are reviewing the recent reports,' Fox and National Geographic said in a statement.

The producers of Cosmos also released a statement of their own which read: 'The credo at the heart of COSMOS is to follow the evidence wherever it leads.

'The producers of COSMOS can do no less in this situation.

'We are committed to a thorough investigation of this matter and to act accordingly as soon as it is concluded.'