Universe Today

SpaceX’s Starship super-rocket got off to a great start for its ninth flight test, but the second stage ran into a host of issues and made an uncontrolled re-entry.

The galaxy cluster Abell S1063 dominates the center of this JWST image. It's a massive cluster of galaxies about 4.5 billion light-years away. While it dominates the picture, it's not the primary target. It serves as a gravitational lens that magnifies even more distant galaxies that appear as glowing streaks of light around its circular edges.

Nuclear Thermal Propulsion (NTP) has stood as a promising potential alternative propulsion technology for decades. Chemical rockets have begun to reach their theoretical maximum efficiency, and their developers have switched their focus to making them cheaper rather than more efficient. NTP should answer that by offering high thrust and specific impulse. NASA's DRACO Program, the standard-bearer for NTP systems, provides a specific impulse of around 900 seconds, about double a traditional chemical rocket, but half that of most ion thrusters. To increase that number even further, researchers at the University of Alabama at Huntsville and The Ohio State University have been working on a novel configuration of NTP called the Centrifugal Nuclear Thermal Rocket (CNTR) that promises almost to double the specific impulse of traditional NTP systems while maintaining similar thrust levels. However, the system has some engineering challenges to overcome, and a new paper coming out in Acta Astronautica describes some incremental progress on making this improved engine a reality.

Modern ground-based telescopes rely on adaptive optics (AO) to deliver clear images. By correcting for atmospheric distortion, they give us exceptional pictures of planets, stars, and other celestial objects. Now, a team at the National Solar Observatory is using AO to examine the Sun's corona in unprecedented detail.

Astronomers have spotted a pulsar in a binary system, taking about 3.6 hours for the stars to orbit one another. Their orbit is so close that, from our vantage point, the pulsar’s radio signals vanish for roughly one-sixth of each cycle—blocked by the companion’s interference. Researchers think that the more massive star died first, exploding as a supernova and collapsing into a neutron star, passing within the atmosphere of the other. It took about 1,000 years to blow away the envelope of material.

Over the past 90 years, astronomers have successfully matched several Chinese historical records of "guest stars" with known supernovae. However, identifying historical novae (smaller stellar explosions) has proven to be far more challenging, with many proposed candidates later turning out to be comets or meteors instead. One particularly debated case involves a guest star recorded in 1408 CE by Chinese astronomers. A team of astronomers now think they may have finally been able to identify the event, a rare nova that could potentially solve this centuries old astronomical mystery.

On May 10th, while striking a selfie to mark its 1,500th day on Mars, NASA’s Perseverance Rover got an unexpected guest star—a towering dust devil swirling in the distance photobombed the shot. The rover was on Witch Hazel Hill, an area on the rim of Jezero Crater that it has been exploring for the last 5 months. The dust devil on the other hand was sneaking into the background from a distance of 5 km away. The selfie image was made up of 59 separate photos taken by the rover using its WATSON camera.

Of the roughly 6,000 exoplanets we've discovered, a significant number are in the apparent habitable zones of their stars. Most are giant planets; either gas giants like Jupiter and Saturn, or ice giants like Uranus and Neptune. Could some of those have habitable exomoons?

Astronomers with the Event Horizon Telescope have developed a new way to observe the radio sky at multiple frequencies, and it means we will soon be able to capture color images of supermassive black holes.