Astronomers rediscover ancient ‘lost’ nova first spotted six centuries ago

A team of astronomers have pinpointed the location of a nova that was last seen almost 600 years ago.

In 1437, Korean astrologers spotted a bright new star in the tail of the constellation Scorpius and observed it for 14 days before it faded from view. Studying the ancient record made by the Royal Imperial Astrologers, modern astronomers determined that what they had seen was a nova explosion but, until now, they were unable to find the binary system that caused it.

“This is the first nova that’s ever been recovered with certainty based on the Chinese, Korean, and Japanese records of almost 2,500 years,” said the study’s lead author Michael Shara, a curator in the American Museum of Natural History’s Department of Astrophysics.

An image of the nova, which was first identified in 1437, taken with the Carnegie SWOPE 1-meter telescope in Chile. Image© K. Ilkiewicz and J. Mikolajewska. Above: a Korean star chart (rotated) first created in 1395, and reproduced in 1687. Image courtesy of Seoul National University / National Geographic Information Resource Map Museum

A nova is essentially a hydrogen bomb on a gigantic scale, produced in a binary system where a star is being devoured by a white dwarf (a dead star). Over roughly 100,000 years, the white dwarf builds up a critical layer of hydrogen that it then blows off, producing a burst of light that can make the star up to 300,000 times brighter than the sun for any period from a few days to a few months.

Shara has tried to locate the Korean nova for several years, teaming up with Durham University’s Richard Stephenson, a historian of ancient Asian astronomical records, and Liverpool John Moores University astrophysicist Mike Bode.  Their recent success came after expanding the search field and discovering the ejected shell of the classical nova. The finding was confirmed with a photographic plate from 1923 taken at the Harvard Observatory station in Peru.

“With this plate, we could figure out how much the star has moved in the century since the photo was taken,” Shara said. “Then we traced it back six centuries, and bingo, there it was, right at the centre of our shell. That’s the clock, that’s what convinced us that it had to be right.”

Photographic plates of the nova taken over six weeks in 1942. Image ©Harvard DASCH

The Peru plate is available online as part of the Digitizing a Sky Century at Harvard (DASCH) project and it was other such DASCH plates that helped reveal the system has now become a dwarf nova. The discovery supports the idea that novae go through an incredibly long-term life cycle, fading for thousands of years after eruption before slowly building back up to full-fledged nova once more.

It was previously believed that “cataclysmic binaries” – novae, novae-like variables and dwarf novae—were separate entities, but the rediscovery of this ancient nova as a dwarf suggests instead that they are one and the same, but at different stages in their lives. Following an eruption, a nova becomes nova-like, before taking the form of a dwarf nova.  Then there may be a period of hibernation, after which it becomes nova-like again and then a fully fledged nova. This cycle repeats, potentially up to 100,000 times over the course of billions of years.

The study, which is published in the journal Nature, was based on observations from the Southern African Large Telescope (SALT), and the Las Campanas Observatories’ Swope and Dupont telescopes.

Scientists, software developers and artists have begun using VR to visualise genes and predict disease

A group of scientists, software developers and artists have taken to using virtual reality (VR) technology to visualise complex interactions between genes and their regulatory elements.

The team, which comprises of members from Oxford University, Universita’ di Napoli and Goldsmiths, University of London, have been using VR to visualise simulations of a composite of data from genome sequencing, data on the interactions of DNA and microscopy data.

When all this data is combined the team are provided with an interactive, 3D image that shows where different regions of the genome sit relative to others, and how they interact with each other.

“Being able to visualise such data is important because the human brain is very good at pattern recognition – we tend to think visually,” said Stephen Taylor, head of the Computational Biology Research Group at Oxford’s MRC Weatherall Institute of Molecular Medicine (WIMM).

“It began at a conference back in 2014 when we saw a demonstration by researchers from Goldsmiths who had used software called CSynth to model proteins in three dimensions. We began working with them, feeding in seemingly incomprehensible information derived from our studies of the human alpha globin gene cluster and we were amazed that what we saw on the screen was an instantly recognisable model.”

The team believe that being able to visualise the interactions between genes and their regulatory elements will allow them to understand the basis of human genetic diseases, and are currently applying their techniques to study genetic diseases such as diabetes, cancer and multiple sclerosis.

“Our ultimate aim in this area is to correct the faulty gene or its regulatory elements and be able to re-introduce the corrected cells into a patient’s bone marrow: to perfect this we have to fully understand how genes and their regulatory elements interact with one another” said Professor Doug Higgs, a principal researcher at the WIMM.

“Having virtual reality tools like this will enable researchers to efficiently combine their data to gain a much broader understanding of how the organisation of the genome affects gene expression, and how mutations and variants affect such interactions.”

There are around 37 trillion cells in the average adult human body, and each cell contains two meters of DNA tightly packed into its nucleus.

While the technology to sequence genomes is well established, it has been shown that the manner in which DNA is folded within each cell affects how genes are expressed.

“There are more than three billion base pairs in the human genome, and a change in just one of these can cause a problem. As a model we’ve been looking at the human alpha globin gene cluster to understand how variants in genes and their regulatory elements may cause human genetic disease,” said Prof Jim Hughes, associate professor of Genome Biology at Oxford University.

Using CRISPR, UK scientists edit DNA of human embryos

For the first time in the UK, scientists have altered human embryos. Using the gene-editing tool CRISPR, the scientists turned off the protein OCT4, which is thought to be important in early embryo development. In doing so, cells that normally go on to form the placenta, yolk sac and foetus failed to develop.

Source: BBC

Tesla and AMD developing AI chip for self-driving cars

Tesla has partnered with AMD to develop a dedicated chip that will handle autonomous driving tasks in its cars. Tesla's Autopilot programme is currently headed by former AMD chip architect Jim Keller, and it is said that more than 50 people are working on the initiative under his leadership.

Source: CNBC

Synthetic muscle developed that can lift 1,000 times its own weight

Scientists have used a 3D printing technique to create an artificial muscle that can lift 1,000 times its own weight. "It can push, pull, bend, twist, and lift weight. It's the closest artificial material equivalent we have to a natural muscle," said Dr Aslan Miriyev, from the Creative Machines lab.

Source: Telegraph

Head of AI at Google criticises "AI apocalypse" scaremongering

John Giannandrea, the senior vice president of engineering at Google, has condemned AI scaremongering, promoted by people like Elon Musk ."I just object to the hype and the sort of sound bites that some people have been making," said Giannandrea."I am definitely not worried about the AI apocalypse."

Source: CNBC

Scientists engineer antibody that attacks 99% of HIV strains

Scientists have engineered an antibody that attacks 99% of HIV strains and is built to attack three critical parts of the virus, which makes it harder for the HIV virus to resist its effects. The International Aids Society said it was an "exciting breakthrough". Human trials will begin in 2018.

Source: BBC

Facebook has a plan to stop fake news from influencing elections

Mark Zuckerberg has outlined nine steps that Facebook will take to "protect election integrity". “I care deeply about the democratic process and protecting its integrity," he said during a live broadcast on his Facebook page. "I don’t want anyone to use our tools to undermine our democracy.”