Thursday's news in 5 minutes.

1. Major soil clue emerges in Karen Ristevski case as police test shovel seized from her home.

Soil samples from shovel found in garage at Karen Ristevski’s home could be key to solving mystery of her death https://t.co/csIml3SJYc pic.twitter.com/ciZwMaiaQ8

— Herald Sun (@theheraldsun) February 22, 2017

Police have reportedly removed a shovel from the Avondale Heights home of Karen Ristevski and have begun testing the soil found on the tool.

The Herald Sun reports that the soil samples found on the shovel – which was found in the garage at the 47-year-old’s home – could be the key to solving the mystery of her death.

Testing has revealed two distinct soil types: one that matches the soil behind the Avondale Heights home Mrs Ristevski shared with her daughter Sarah and husband Borce, and another that matched soil found in the Gisborne-Macedon area.

Mrs Ristevski’s remains were found in bushland at Mt Macedon on Monday this week. She was last seen on June 29, 2016.

“Each type of soil has its own specific characteristics, so it is possible to tell the difference,” Dr Rob Fitzpatrick, director of the Centre for Australian Forensic Soil Science at the CSIRO, told The Herald Sun.

“Let’s say there was a murder on the pitch at the MCG: that type of soil would be unique to that area of grass.”

Detective Inspector Stephen Dennis has declined to comment on the shovel and soil testing.

“As you can appreciate, the investigation is continuing and it would be inappropriate to provide a running commentary,” he said.

7 News reports that initial autopsy results on Mrs Ristevski’s body failed to find any visible signs of injury, or any evidence that “she was attacked by a weapon”.

A lawyer for Karen Ristevki’s husband, Borce, told the media yesterday that he was the “number one suspect” in the investigation into her death.

2. NASA scientists have just discovered seven ‘Earthlike’ planets.

Scientists discover 7 “Earthlike” planets orbiting a nearby starhttps://t.co/E5dGHBghlH

— Washington Post (@washingtonpost) February 22, 2017

In a highly-anticipated announcement, NASA has revealed that a single star close to Earth is home to seven ‘Earthlike’ planets that could harbour life, The Washington Post reports.

It’s the first time astronomers have ever detected so many terrestrial planets – which they say are “warm” and “rocky” – orbiting a single star. The star is just 39 light-years away from Earth.

The discovery was released in the journal Nature, and researchers say the planets are the best place in the galaxy to search for life beyond Earth.

“Before this, if you wanted to study terrestrial planets, we had only four of them and they were all in our solar system,” the report’s lead author Michaël Gillon, said.

“Now we have seven Earth-sized planets to expand our understanding. Yes, we have the possibility to find water and life. But even if we don’t, whatever we find will be super interesting.”

The newly discovered solar system closely resembles our own, except the star at its centre is less than a tenth the size of the sun and the closet planet takes just a day and a half to complete an orbit.

3. NSW high school teacher, 25, refused bail after allegedly having sex with a student.

Wollongong High teacher Kurt Majoor accused of having sex with a student. https://t.co/DV2spydZJp @PeterFegan7 https://t.co/kQJ171SW9n

— 7 News Sydney (@7NewsSydney) February 22, 2017

A Wollongong high school teacher has been refused bail after he was accused of having sex with one of his students, 7 News reports.

Kurt Majoor was arrested at his home on Wednesday and charged with one count of sexual intercourse with a person under care.

The physical education teacher is accused of grooming one of his 17-year-old students by sending her sexually explicit text messages and images via social media.

Police alleged Majoor also arranged to meet the student at the beach for sex before school on Monday last week.

It’s alleged the teenager spoke to her friends about the incident after Majoor gave her a lift back to school after their meeting.

“On these allegations he’s completely abused that trust,” police prosecutor Sergeant Shannon Ryan said when Majoor was refused bail on Wednesday.

“There was a degree of planning associated with this…it was by no means opportunistic.”

The teacher has been suspended with pay and is due to appear back in court in April.

4. “He didn’t stop”: Daughter tells court of trying to stop father stabbing her mother to death.

Daughter tried to stop Haydar Haydar stabbing his wife Salwa, NSW Supreme Court told https://t.co/LWgzmbNmkt via @smh @melaniekembrey

— Louise Hall (@LouiseCHall) February 22, 2017

Ola Haydar has told the NSW Supreme Court how she tried to stop her father, Haydar Haydar, from stabbing her mother to death in March 2015.

Hayder was just 18 when she tried to save her mother’s life, the Sydney Morning Herald reports.

“I heard my mum scream…I remember thinking ‘I think he hit her’ and I ran,” she told the court yesterday.

“[I saw] Mum backed up in a corner and he stabbed her in her back.I tried to get in the middle of it, to pull him away from her…He didn’t stop, he kept going.

“I was trying to hold his hand back, the one that had the knife, and trying to push him off her but I couldn’t. [I was] saying ‘What are you doing? Oh my god, you’re going to kill her’.”

60-year-old Haydar Haydar has pleaded not guilty to murder but guilty to the manslaughter of his wife, 45-year-old Salwa Haydar, who was stabbed to death in front of their Bexley townhouse in 2015.

Ola told the court that her parents had a “tumultuous relationship” and had discussed divorce a number of times.

Mr Haydar allegedly wrongly suspected his wife was having an affair with a male colleague. She was stabbed 30 times.

After the attack, Haydar walked in to police station and confessed that he had stabbed his wife.

“My wife, I just stabbed my wife. I can’t feel anything,” he reportedly told the constable on duty.

5. Trump administration set to change Obama’s transgender student bathroom rules.

Trump administration to change transgender student bathroom rules https://t.co/rFSGbj9aWY pic.twitter.com/DSBskgPZ4Q

— USA TODAY (@USATODAY) February 22, 2017

US President Donald Trump’s Republican administration looks to be preparing to reverse a policy on transgender rights put in place by President Barack Obama, USA Today reports.

The administration is set to issue new guidance outlining which restrooms transgender students can use.

Last year, the Obama administration issued guidelines which required schools to allow transgender students to use restrooms matching their chosen gender rather than their birth gender. Thirteen states challenged the move, prompting a federal judge to issue a nationwide enforcement on the guidance.

White House Press Secretay Sean Spicer hinted at the changes this week, telling reporters that President Trump “has maintained for a long time that this is a states’ rights issue and not one for the federal government”.

Several LGBT rights groups have already responded to the potential change in policy.

“This is about adults trying to make political hay out of children, and it is not OK,” Mara Keisling, executive director of the National Centre for Transgender Equality, said.

“We are going to push this over and over again until our students are protected fully.”

Further announcements on the issue are expected to be released shortly.

6. Warning for Melbourne cruise passengers who may have been exposed to Hepatitis E.

Hepatitis E warnings have been issued to passengers who boarded two recent cruises in Melbourne. #9News https://t.co/34OZPRInoZ

— Nine News Melbourne (@9NewsMelb) February 22, 2017

Passengers who boarded two recent cruises leaving from Melbourne have been warned they may have been exposed to Hepatitis E, 9 News reports.

The Department of Health and Human Services has alerted passengers who travelled on the Golden Princess between February 8 and 15 that a crew member had been suffering from the illness at the time.

Hepatitis E is an illness of the liver, with symptoms including jaundice, fatigue, nausea and loss of appetite.

Person-to-person transmission of the illness is rare, and it is usually spread by eating or drinking contaminated food or water.

Passengers were at a “low risk” of infection, said Victoria’s Chief Health Officer Professor Charles Guest, and were unlikely to become unwell a a result of the possible exposure.

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