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SpaceX, Blue Origin and United Launch Alliance will compete for National Security Space Launch contracts worth up to $5.6 billion across fiscal years 2025 through 2029.

Periods of excess electricity production are on the rise thanks to the growth of renewable energy, forcing commercial power generators to sell for negative prices. Unfortunately, this doesn't mean lower household bills

Periods of excess electricity production are on the rise thanks to the growth of renewable energy, forcing commercial power generators to sell for negative prices. Unfortunately, this doesn't mean lower household bills

A container port the Indian government plans for this remote island threatens unique Indigenous cultures and biodiversity

The land, water and air around us are chock-full of DNA from fungi that scientists can’t identify

Different approaches can support varied forms of memory

Cosmic happenstance and biological evolution come together to create a road map to the stars

Climate models suggest that a possible scheme to cool the western US by making clouds brighter could work under current conditions, but may have severe unintended consequences in a future scenario

Climate models suggest that a possible scheme to cool the western US by making clouds brighter could work under current conditions, but may have severe unintended consequences in a future scenario

Saturn pumps into space varying amounts of heat based on its seasons, which drives planet-wide storms, data from NASA's Cassini mission has revealed.

To unravel the effects of melting sea ice, researchers drill the frozen waters around Antarctica and receive a surprise visit from a group of penguins.

The two brightest stars of summer balance across the zenith. Arcturus and Vega represent the two commonest spectral types, and colors, of all the naked-eye stars in the sky.

The post This Week's Sky at a Glance, June 21 – 30 appeared first on Sky & Telescope.

Week in images: 17-21 June 2024

Image: This Copernicus Sentinel-2 image shows Adam’s Bridge, a chain of shoals linking India and Sri Lanka.

Social media is flooding users with bad information about birth control. Providers need to fight back by rebuilding trust in reproductive health care

From the 1960 astronomical catalog of

Since it began operating in 2022, the James Webb Space Telescope (JWST) has revealed some surprising things about the Universe. The latest came when a team of researchers used Webb‘s Mid-Infrared Instrument (MIRI) to observe Rho Ophiuchi, the closest star-forming nebula to Earth, about 400 light-years away. While at least five telescopes have studied the region since the 1970s, Webb’s unprecedented resolution and specialized instruments revealed what was happening at the heart of this nebula.

For starters, while observing what was thought to be a single star (WL 20S), the team realized they were observing a pair of young stars that formed 2 to 4 million years ago. The MIRI data also revealed that the twin stars have matching jets of hot gas (aka stellar jets) emanating from their north and south poles into space. The discovery was presented at the 244th meeting of the American Astronomical Society (224 AAS) on June 12th. Thanks to additional observations made by the Atacama Large Millimeter/submillimeter Array (ALMA), the team was surprised to notice large clouds of dust and gas encircling both stars.

Given the twins’ age, the team concluded that these may be circumstellar disks gradually forming a system of planets. This makes WL 20S a valuable find for astronomers, allowing them to watch a solar system take shape. As noted, the Rho Ophiuchi nebula has been studied for decades by infrared telescopes, including the Spitzer Space Telescope and the Wide-field Infrared Explorer (WISE), the Infrared Telescope Facility (IRTF) at the Mauna Kea Observatory, the Hale 5.0-meter telescope the Palomar Observatory, and the Keck II telescope.

This WL 20 star group image combines data from the Atacama Large Millimeter/submillimeter Array and the Mid-Infrared Instrument on NASA’s Webb telescope. Credit: NSF/NRAO/NASA/JPL-Caltech/B. Saxton

Infrared astronomy is necessary when studying particularly dusty nebulae since the clouds of dust and gas obscure most of the visible light of the stars within them. Thanks to its advanced infrared optics, Webb was able to detect slightly longer wavelengths using its MIRI instrument. Mary Barsony, an astronomer with the Carl Sagan Center for the Study of Life in the Universe (part of the SETI Institute), was the lead author of a new paper that describes the results. As she related in a recent NASA press statement.

“Our jaws dropped. After studying this source for decades, we thought we knew it pretty well. But we would not have known this was two stars or that these jets existed without MIRI. That’s really astonishing. It’s like having brand new eyes.”

Radio telescopes are another way to study nebulae, though they are not guaranteed to reveal the same features as infrared instruments. In the case of WL 20S, the absorbed light was visible in the submillimeter range, making ALMA the ideal choice for follow-up observations. However, the high-resolution mid-infrared data was needed to discern WL 20S as a pair of stars with individual accretion disks. This allowed the team to resolve stellar jets composed of ionized gas that is not visible at submillimeter wavelengths.

“The power of these two telescopes together is really incredible. If we hadn’t seen that these were two stars, the ALMA results might have just looked like a single disk with a gap in the middle. Instead, we have new data about two stars that are clearly at a critical point in their lives, when the processes that formed them are petering out.”

The combined MIRI and ALMA results revealed that the twin stars are nearing the end of their formation period and may already have a system of planets. Future observations of these stars with Webb and other telescopes will enable astronomers to learn more about how young stars transition from formation to their main sequence phase. “It’s amazing that this region still has so much to teach us about the life cycle of stars,” said Ressler. “I’m thrilled to see what else Webb will reveal.”

Further Reading: NASA

The post Matched Twin Stars are Firing Their Jets Into Space Together appeared first on Universe Today.

Space debris is a major problem for space exploration. There are millions of pieces up there in orbit from flecks of paint to defunct satellites. It is a known challenge to space exploration creating a shell of uncontrolled debris which could cause damage to orbiting craft or astronauts. A team at Astroscale have a spacecraft in orbit whose singular purpose has been to rendezvous with a defunct Japanese upper-stage rocket module. On arrival it is to survey the debris to test approach and survey techniques to ultimately inform how we can remove them from orbit.

Space debris, or space junk, is exactly what it says; pieces of human made objects orbiting Earth that are no longer required. It’s not just unwanted items though, many pieces are the result of collisions and at speeds in excess of 28,000 kilometres per hour they pose a real threat to astronauts and operational spacecraft in low earth orbit.

Taking a bleak view, NASA scientists Donald Kessler proposed a scenario where the shear volume of debris is high enough that collisions could cascade into a chain reaction. The chain reaction of collisions could ultimately lead to an exponential growth in debris and even cut off our access to space. It may seem a pessimistic view but some computer modelling of the scenario does give strong indications that this may be the case if we don’t act now.

A map of space debris orbiting Earth. Credit: European Space Agency

There have been numerous, almost fanciful ideas proposed from great big balloons covered in sticky stuff like giant fly paper in orbit to pickup bits and bobs floating around. Nets have also been proposed even lasers to piece by piece destroy the offending objects. If I were a betting man I would go for something along the lines of a net travelling through space at similar velocity, scooping up the debris and controlling its gentle deorbit until either landed safely for collection or burnt up in the atmosphere. 

The ideas are there, what we are lacking, is data to assess their feasibility. Enter Astroscale, a company that was founded in 2013 and develops in-orbit solutions. They have been selected by the Japan Aerospace Exploration Agency – JAXA – for the first phase of Commercial Removal of Debris Demonstration. The purpose to demonstrate how the technology for removing large pieces of debris. This has led to the development of ADRAS-J (Active Debris Removal by Astroscale-Japan.)

ADRAS-J was launched on 18 February and started its rendezvous phase four days later. On 9 April it began its approach from a few hundred kilometres and from 16 April it began its automated relative navigation approach taking it to within a few hundred metres using the onboard infrared camera. On 23 May it approached to 50 metres, a first for any spacecraft to arrive in such proximity to a large piece of debris. 

The item is the upper stage of a Japanese rocket that measures 11 metres long and 4 metres in diameter. Now the two are so close, ADRAS-J will demonstrate proximity operations and collect images of the rocket to assess its movements. This is a particularly interesting object for ADRAS-J to study becausey it has no technology or infrastructure to enable docking or servicing so is a challenging piece of debris to remove.

Source : Historic Approach to Space Debris: Astroscale’s ADRAS-J Closes in by 50 Meters

The post Astroscale Closes Within 50 Meters of its Space Junk Target appeared first on Universe Today.

Neutron stars with surface temperatures millions of degrees cooler than expected rule out a swathe of possible models to describe the physics of such objects.