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With few states tracking who is being homeschooled and what they are learning, an untold number of U.S. children are at risk of a poor education or even abuse

Explore the new science of weird chemistry, anthropogenic evolution and near-death experiences

Forestry is deadly. Could automating some logging tasks help?

Scientists are putting together a catalog of communications from belugas’ forehead “melon”

Scientists think they’ve cracked the long-standing mystery of attraction among particles with a similar charge

Adam Higginbotham's new book "Challenger: A True Story of Heroism & Disaster on the Edge of Space" explores the fateful internal NASA decisions that partly led to Challenger's sudden destruction upon liftoff.

Underwater data centres being installed off the coasts of China, the US and Europe could be disrupted by sounds from military-grade sonar on ships and submarines, or even whales

Underwater data centres being installed off the coasts of China, the US and Europe could be disrupted by sounds from military-grade sonar on ships and submarines, or even whales

We face a moment of opportunity—and competition—in bringing digital twin technology to patients

The coming settlement of the High Frontier doesn’t have to be a repeat of the violent conquests and colonization of history. We will not take space from anyone, and we can give it to everyone.

A white dwarf star orbiting a sun-like star was thought to be impossibly small, but now astronomers have found another star in the system that solves the puzzle

A white dwarf star orbiting a sun-like star was thought to be impossibly small, but now astronomers have found another star in the system that solves the puzzle

Are you ready for the greatest story ever told? Launched in France on 25 April 2024, Space Odyssey is the first complete history of space in graphic novel form. Drawing on the latest scientific and historical sources, it tells the story of the men and women who pioneered humankind's journey into space.

Genetic analysis of 50,000-year-old Neanderthal skeletons has uncovered the remnants of three viruses related to modern human pathogens, and the researchers think they could be recreated

Genetic analysis of 50,000-year-old Neanderthal skeletons has uncovered the remnants of three viruses related to modern human pathogens, and the researchers think they could be recreated

I can remember when Perseverance was launched, travelled out into the Solar System and landed on Mars in February 2021.  In all the time since it arrived, having clocked up 1000 days of exploration, it has collected 23 samples from different geological areas within the Jezero Crater. The area was once home to an ancient lake and if there is anywhere on Mars to find evidence of ancient (fossilised) life, it is here. 

The date was 30 July 2020 when a gigantic Atlas V-541 rocket roared off the launchpad from Cape Canaveral in Florida. On board was the Perseverance rover, on its way to Mars. It arrived around 7 months later, entered the Martian atmosphere and successfully landed using a complex sequence of parachutes, retrorockets and for the first time, a sky crane to lower it from a hovering platform. Its chief purpose on Mars was to explore the geology, climate and atmospheric conditions as a precursor to human exploration. 

A United Launch Alliance Atlas V rocket with NASA’s Mars 2020 Perseverance rover onboard launches from Space Launch Complex 41 at Cape Canaveral Air Force Station, Thursday, July 30, 2020, from NASA’s Kennedy Space Center in Florida. The Perseverance rover is part of NASA’s Mars Exploration Program, a long-term effort of robotic exploration of the Red Planet. Photo Credit: (NASA/Joel Kowsky)

The landing site, the Jezero Crater, was chosen because previous orbital studies revealed clear evidence of an ancient lake that once filled the crater. It is thought that water is a key ingredient to the evolution of life so if there had been a body of water, then there is a greater chance of life evolving. Studying the rocks here is like taking a flick through the history books as it preserves signs of ancient life and also ancient environmental conditions. 

The crater had been formed, like the majority of other craters in the Solar System from some form of impact event. In the case of Jezero it was an asteroid impact around 4 billion years ago. On its arrival at the crater the floor was soon discovered to be made of igneous rock, formed from a huge underground chamber of magma and bought to the surface through volcanic activity. Since then, other types of rock from sand and mud were found providing evidence of the presence of water in Mars’ distant past. 

Jezero Crater on Mars. Credit: NASA/JPL-Caltech/ASU

By the time Perseverance had hit the 1000 day anniversary of its exploration of the red planet it had collected the rock samples, safely packaged them up ready for collection and by and large, completed its exploration of the ancient lake bed. One sample in particular which has been called ‘Lefroy Bay’ has been found to contain fine grained silica. This material is commonly found on Earth and known to preserve fossils. Another of the samples contains phosphate which, on Earth is most definitely associated with biological processes. Both of these contain carbon which can be used to study the environmental conditions from when the rock formed. 

Jezero crater is a big place, 45 kilometres across so deciding on where to collect the samples was challenging. When a target site had been identified, Perseverance would first use its abrasion tool to wear away the surface and then use the onboard instruments such as PIXL, the Planetary Instrument for X-ray Lithochemistry. The instruments on board have the ability to detect both microscopic, fossil-like structures and also to identify chemical changes left behind by ancient microbes. Alas to date, whilst Perseverance has achieved an amazing amount, the detection of signs of life have alluded the rover. 

Source : NASA’s Perseverance Rover Deciphers Ancient History of Martian Lake

The post Perseverance Wraps Up Over 1,000 Days on Mars. Still Going Strong appeared first on Universe Today.

What happens when a black hole devours a star?

Back in the year 2000, Epsilon Eridani b was discovered. It is a Jupiter-like exoplanet 10.5 light years away but it has taken decades of observations to learn more about the planet. One thing that remains a mystery is it’s orbit which, until recently has been unknown. There has never been a direct image of the planet either, so now, it’s the turn of JWST to see what it can do. 

The concept of exoplanets has been around for a few decades now but the first confirmed discovery occurred in 1992. Astronomers at the Arecibo Observatory discovered a number of Earth-mass planets orbiting around the pulsar PSR B1257+12. Since then, over 5,000 planets have been discovered around other star systems. Astronomers use a number of Studying them once they have been confirmed requires more direct study.

The Arecibo Radio Telescope Credit: UCF

One such exoplanet is known as Epsilon Eridani b which also goes by the name AEgir. Exoplanets are named after their host star (in this case Epsilon Eridani) and the letter ‘b’ designates that it was the first exoplanet discovered around that star. The next to be discovered would be ‘c’ and so on although in the case of Epsilon Eridani it is the only planet. It is thought to orbit around the star at a distance of 3.5 astronomical units (where 1 AU is the average distance between the Sun and Earth) and takes about 7.6 years to complete one orbit.  

One area of exoplanet study that has been lacking over recent years is the study of the surface and atmospheric conditions, in particular a study into their potential habitability. Cold exoplanets seem to have received the least study due to their faint appearance in the mid-infrared wavelength. Due to the properties of these cold planets, direct imaging techniques are required and must employ high contrast processes.  To date, no instrument has been capable of delivering. 

The crux of the challenge is that the cold exoplanets have no intrinsic energy source and only re-use the radiation from the host star. Their luminosity is based upon their size and distance from host star but usually the radiation is at the same wavelength as the emission from the star. To address this challenge, a paper has been published in ‘Astronomy & Astrophysics’ journal by a team led by C. Tschudi from the Institute for Particle Physics and Astrophysics in Switzerland.

The paper provides an insight into high contrast observations of Epsilon Eridani taken in 20198 and 2020 using the VLT (Very Large Telescope). Using the SPHERE instrument (Spectro-Polarimetric High-contrast Exoplanet Research) as part of the ongoing RefPlanets programme, the team were able to use polarising technology to search for signals from the planet. 

In mid-August 2010 ESO Photo Ambassador Yuri Beletsky snapped this amazing photo at ESO’s Paranal Observatory. A group of astronomers were observing the centre of the Milky Way using the laser guide star facility at Yepun, one of the four Unit Telescopes of the Very Large Telescope (VLT). Yepun’s laser beam crosses the majestic southern sky and creates an artificial star at an altitude of 90 km high in the Earth’s mesosphere. The Laser Guide Star (LGS) is part of the VLT’s adaptive optics system and is used as a reference to correct the blurring effect of the atmosphere on images. The colour of the laser is precisely tuned to energise a layer of sodium atoms found in one of the upper layers of the atmosphere — one can recognise the familiar colour of sodium street lamps in the colour of the laser. This layer of sodium atoms is thought to be a leftover from meteorites entering the Earth’s atmosphere. When excited by the light from the laser, the atoms start glowing, forming a small bright spot that can be used as an artificial reference star for the adaptive optics. Using this technique, astronomers can obtain sharper observations. For example, when looking towards the centre of our Milky Way, researchers can better monitor the galactic core, where a central supermassive black hole, surrounded by closely orbiting stars, is swallowing gas and dust. The photo, which was chosen as Astronomy Picture of the Day for 6 September 2010 and Wikimedia Picture of the Year 2010, was taken with a wide-angle lens and covers about 180 degrees of the sky.   This image is available as a mounted image in the ESOshop.   #L

Unfortunately the team were unable to successfully detect Epsilon Eridani b despite a total exposure time of 38.5 hours spread over 12 nights. This was however, useful at understanding the limitations of the instrumentation. What next then? Well it looks like we have to wait for a next generation of infrared sensitive instruments to peer deeper into the system. The James Webb telescope is a fine example of such a device and, once it turns its sights onto Epsilon Eridani maybe the mysteries will finally be resolved.

Source : SPHERE RefPlanets: Search for ? Eridani b and warm dust

The post Astronomers Try to Directly Observe Epsilon Eridani b. No Luck. Maybe Webb Can Find it? appeared first on Universe Today.

OpenAI's new ChatGPT model, called GPT-4o, provides more human-like interactions through a voice mode, and it is capable of conversations that incorporate text, audio and video in real time