Space News & Blog Articles

Missions to asteroids have been on a tear recently. Visits by Rosetta, Osirix-REX, and Hayabusa2 have all visited small bodies and, in some cases, successfully returned samples to the Earth. But as humanity starts reaching out to asteroids, it will run into a significant technical problem – bandwidth. There are tens of thousands of asteroids in our vicinity, some of which could potentially be dangerous. If we launched a mission to collect necessary data about each of them, our interplanetary communication and control infrastructure would be quickly overwhelmed. So why not let our robotic ambassadors do it for themselves – that’s the idea behind a new paper from researchers at the Federal University of São Paulo and Brazil’s National Institute for Space Research.

The paper primarily focuses on the control problem of what to do when a spacecraft is approaching a new asteroid. Current missions take months to approach and require consistent feedback from ground teams to ensure the spacecraft understands the parameters of the asteroid it’s approaching – especially the gravitational constant.

Some missions have seen more success with that than others – for example, Philase, the lander that went along with Rosetta, had trouble when it bounced off the surface of comet 67P/Churyumov-Gerasimenko. As the authors pointed out, part of that difference was a massive discrepancy between the actual shape of the comet and the observed shape that telescopes had seen before Rosetta arrived there. 

Even more successful missions, such as OSIRIS-Rex, take months of lead-up time to complete relatively trivial maneuvers in the context of millions of kilometers their overall journey takes them. For example, it took 20 days for OSIRIX-Rex to perform multiple flybys at 7 km above the asteroid’s surface before its mission control deemed it safe to enter a stable orbit.

One of the significant constraints the mission controllers were looking at was whether they could accurately calculate the gravitational constant of the asteroid they were visiting. Gravity is notoriously difficult to determine from far away, and its miscalculation led to the problems with Philae. So, can a control scheme do to solve all of these problems?

I remember reading about an audacious mission to endeavour to drill through the surface ice of Europa, drop in a submersible and explore the depths below. Now that concept may be taking a step closer to reality with researchers working on technology to do just that. Worlds like Europa are high on the list for exploration due to their potential to harbour life. If technology like the SLUSH probe (Search for Life Using Submersible Head) work then we are well on the way to realising that dream. 

The search for life has always been something to captivate the mind. Think about the diversity of life on Earth and it is easy to see why we typically envisage creatures that rely upon sunlight, food and drink. But on Earth, life has found a way in the most inhospitable of environments, even at the very bottom of the ocean. The Mariana’s Trench is deeper than Mount Everest is tall and anything that lives there has to cope with cold water, crushingly high pressure and no sunlight. Seems quite alien but even here, life thrives such as the deep-sea crustacean Hirondellea Gigas – catchy name. 

Europa, one of the moon’s of Jupiter has an ice crust but this covers over a global ocean of liquid water.  The conditions deep down in the ocean of Europa might not be so very different from those at the bottom of the Mariana’s Trench so it is here that a glimmer of hope exists to find other life in the Solar System. Should it exist, getting to it is the tricky bit. It’s not just on Europa but Enceladus and even Mars may have water underneath ice shelves. Layers of ice up to a kilometre thick might exist so technology like SLUSH has been developed to overcome. 

The technology is not too new though since melt probes like SLUSH have been tested before. The idea is beautifully simple.  The thermo-mechanical probe uses a drilling mechanism to break through the ice and then the heat probe to partially melt the ice chips, forming slush to enable their transportation to behind the probe as it descends. 

The probe, which looks rather like a light sabre, is then able to transmit data from the subsurface water back to the lander. A tether system is used for the data transmission using conductive microfilaments and an optical fibre cable. Intriguingly and perhaps even cunningly, should the fibre cable break (which is a possibility due to tidal stresses from the ice) then the microfilaments will work as an antenna.  They can then be tuned into by the lander to resume data transmission. The tether is coiled up and housed inside spools which are left behind in the ice as the spool is emptied. I must confess my immediate thought here was ‘litter’! I accept we have to leave probes in order to explore but surely we can do it without leaving litter behind! However there is a reason for this too. As the spools are deployed, they act as receivers and transmitters to allow the radio frequencies to travel through the ice. 

It has often been likened to talcum powder. The ultra fine lunar surface material known as the regolith is crushed volcanic rock. For visitors to the surface of the Moon it can be a health hazard, causing wear and tear on astronauts and their equipment, but it has potential. The fine material may be suitable for building roads, landing pads and shelters. Researchers are now working to analyse its suitability for a number of different applications.

Back in the summer of 1969, Armstrong and Aldrin became the first visitors from Earth to set foot on the Moon. Now, 55 years on and their footprints are still there. The lack of weathering effects and the fine powdery material have held the footprints in perfect shape since the day they were formed. Once we – and I believe this will happen – establish lunar bases and even holidays to the Moon those footprints are likely still going to be there. 

There are many challenges to setting up permanent basis on the Moon, least of which is getting all the material there. I’ve been embarking on a fairly substantial home renovation over recent years and even getting bags of cement and blocks to site has proved a challenge. Whilst I live in South Norfolk in UK (which isn’t the easiest place to get to I accept) the Moon is even harder to get to. Transporting all the necessary materials over a quarter of a million kilometres of empty space is not going to be easy. Teams of engineers and scientists are looking at what materials can be acquired on site instead of transporting from Earth. 

The fine regolith has been getting a lot of attention for this very purpose and to that end, mineralogist Steven Jacobsen from the Northwestern University has been funded by NASAs Marshall Space Flight Centre to see what it back be used for. In addition NASA has partnered with ICON Technology, a robotics firm to explore lunar building technologies using resources found on the Moon. A key challenge with the lunar regolith though is that samples can vary considerably depending on where they are collected from. Jacobsen is trying to understand this to maximise construction potential. 

ICON were awarded the $57.2 million grant back in November 2022 to develop lunar construction methods. Work had already begun on space based construction, again from ICON in their Project Olympus. This didn’t just focus on the Moon though, Mars was also part of the vision to create construction techniques that could work wherever they were employed. 

The Vera C. Rubin Observatory, formerly the Large Synoptic Survey Telescope (LSST), was formally proposed in 2001 to create an astronomical facility that could conduct deep-sky surveys using the latest technology. This includes a wide-field reflecting telescope with an 8.4-meter (~27.5-foot) primary mirror that relies on a novel three-mirror design (the Simonyi Survey Telescope) and a 3.2-megapixel Charge-Coupled Device (CCD) imaging camera (the LSST Camera). Once complete, Rubin will perform a 10-year survey of the southern sky known as the Legacy Survey of Space and Time (LSST).

While construction on the observatory itself did not begin until 2015, work began on the telescope’s digital cameras and primary mirror much sooner (in 2004 and 2007, respectively). After two decades of work, scientists and engineers at the Department of Energy’s (DOE) SLAC National Accelerator Laboratory and their collaborators announced the completion of the LSST Camera – the largest digital camera ever constructed. Once mounted on the Simonyi Survey Telescope, this camera will help researchers observe our Universe in unprecedented detail.

The Vera C. Rubin Observatory is jointly funded by the U.S. National Science Foundation (NSF) and the U.S. Department of Energy (DOE) and is cooperatively operated by NSF NOIRLab and SLAC. When Rubin begins its ten-year survey (scheduled for August 2025), it will help address some of the most pressing and enduring questions in astronomy and cosmology. These include understanding the nature of Dark Matter and Dark Energy, creating an inventory of the Solar System, mapping the Milky Way, and exploring the transient optical sky (i.e., objects that vary in location and brightness).

A schematic of the LSST Camera. Note the size comparison; the camera will be the size of a small SUV. Credit: Vera Rubin Observatory/DOE

The LSST Camera will assist these efforts by gathering an estimated 5,000 terabytes of new raw images and data annually. “With the completion of the unique LSST Camera at SLAC and its imminent integration with the rest of Rubin Observatory systems in Chile, we will soon start producing the greatest movie of all time and the most informative map of the night sky ever assembled,” said Željko Ivezic, an astronomy professor at the University of Washington and the Director of Rubin Observatory Construction in a NoirLab press release.

When light strikes the atmosphere all sorts of interesting things can happen. Water vapor can split sunlight into a rainbow arc of colors, corpuscular rays can stream through gaps in clouds like the light from heaven, and halos and sundogs can appear due to sunlight reflecting off ice crystals. And then there is the glory effect, which can create a colorful almost saint-like halo around objects.

Like rainbows, glories are seen when facing away from the light source. They are often confused with circular rainbows because of their similarity, but glories are a unique effect. Rainbows are caused by the refraction of light through water droplets, while glories are caused by the wave interference of light. Because of this, a glory is most apparent when the water droplets of a cloud or fog are small and uniform in size. The appearance of a glory gives us information about the atmosphere. We have assumed that some distant exoplanets would experience glories similar to Earth, but now astronomers have found the first evidence of them.

The observations come from the Characterising ExOplanet Satellite (Cheops) as well as observations from other observatories of an exoplanet known as WASP-76b. It’s not the kind of exoplanet where you’d expect a glory to appear. WASP-76b is not a temperate Earth-like world with a humid atmosphere, but a hellish hot Jupiter with a surface temperature of about 2,500 Kelvin. Because of this, the team wasn’t looking for extraterrestrial glories but rather studying the odd asymmetry of the planet’s atmosphere.

WASP-76b orbits its star at a tenth of the distance of Mercury from the Sun. At such a close distance the world is likely tidally locked, with one side forever boiling under its sun’s heat and the other side always in shadow. No such planet exists in our solar system, so astronomers are eager to study how this would affect the atmosphere of such a world. Previous studies have shown that the atmosphere is not symmetrical. The star-facing side is puffed up by the immense heat, while the atmosphere of the dark side is more dense.

For three years the team observed WASP-76b as it passed in front of and behind its star, capturing data on the intersection between the light and dark side. They found that on the planet’s eastern terminator (the boundary between light and dark sides) there was a surprising increase in light. This extra glow could be caused by a glory effect. It will take more observations to confirm this effect but if verified it will be the first glory observed beyond our solar system. Currently, glories have only been observed on Earth and Venus.

Astronomers routinely provide the ages of the stars they study. But the methods of measuring ages aren’t 100% accurate. Measuring the ages of distant stars is a difficult task.

The Nancy Grace Roman Space Telescope should make some progress.

Stars like our Sun settle into their main sequence lives of fusion and change very little for billions of years. It’s like watching middle-aged adults go about their business during their working lives. They get up, drive to work, sit at a desk, then drive home.

But what can change over time is their rotation rate. The Sun now rotates about once a month. When it was first formed, it rotated more rapidly.

But over time, the Sun’s rotation rate, and the rotation rate of stars the same mass or lower than the Sun’s, will slow down. The slowdown is caused by interactions between the star’s magnetic fields and the stellar wind, the stream of high-energy protons and electrons emitted by stars. Over time, these interactions reduce a star’s angular momentum, and its rotation slows. The phenomenon is called “magnetic braking,” and it depends on the strength of a star’s magnetic fields.

Since it began operations in July 2022, the James Webb Space Telescope (JWST) has fulfilled many scientific objectives. In addition to probing the depths of the Universe in search of galaxies that formed shortly after the Big Bang, it has also provided the clearest and most detailed images of nearby galaxies. In the process, Webb has provided new insight into the processes through which galaxies form and evolve over billions of years. This includes galaxies like Messier 82 (M82), a “starburst galaxy” located about 12 million light-years away in the constellation Ursa Major.

Also known as the “Cigar Galaxy” because of its distinctive shape, M82 is a rather compact galaxy with a very high star formation rate. Roughly five times that of the Milky Way, this is why the core region of M82 is over 100 times as bright as the Milky Way’s. Combined with the gas and dust that naturally obscures visible light, this makes examining M82’s core region difficult. Using the extreme sensitivity of Webb‘s Near-Infrared Camera (NIRCam), a team led by the University of Maryland observed the central region of this starburst galaxy to examine the physical conditions that give rise to new stars.

The team was led by Alberto Bollato, an astronomy professor at the University of Maryland and a researcher with the Joint Space-Science Institute (JSSI). He was joined by researchers from NASA’s Jet Propulsion Laboratory, NASA Ames, the European Space Agency (ESA), the Space Telescope Science Institute (STScI), the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), the Max-Planck-Institut für Astronomie (MPIA), National Radio Astronomy Observatory (NRAO), the Infrared Processing and Analysis Center (IPAC-Caltech) and multiple universities, institutes, and observatories. Their findings are described in a paper accepted for publication in The Astrophysical Journal.

Annotated image of the starburst galaxy Messier 82 captured by Hubble (left) and Webb’s NIRCam (right). Credit: NASA/ESA/CSA/STScI/Alberto Bolatto (UMD)

Their observations were part of a Cycle 1 General Observations (GO) project – for which Bollato is the Principal Investigator (PI) – that used NIRCam data to examine the “prototypical starbursts” NGC 253 and M82 and their “cool” galactic winds. Such galaxies remain a source of fascination for astronomers because of what they can reveal about the birth of new stars in the early Universe. Starbursts are galaxies that experience rapid and efficient star formation, a phase that most galaxies went through during the early history of the Universe (ca. 10 billion years ago). Studying early galaxies in this phase is challenging due to the distances involved.

The region near the Milky Way’s centre is dominated by the supermassive black hole that resides there. Sagittarius A*’s overwhelming gravity creates a chaotic region where tightly packed, high-speed stars crash into one another like cars in a demolition derby.

These collisions and glancing blows change the stars forever. Some become strange, stripped-down, low-mass stars, while others gain new life.

The Milky Way’s supermassive black hole (SMBH) is called Sagittarius A* (Sgr. A*). Sgr. A* is about four million times more massive than the Sun. With that much mass, the much smaller stars nearby are easily affected by the black hole’s powerful gravity and are accelerated to rapid velocities.

In the inner 0.1 parsec, or about one-third of a light-year, stars travel thousands of kilometres per second. Outside that region, the pace is much more sedate. Stars beyond 0.1 parsec travel at hundreds of km/s.

But it’s not only the speed that drives the collisions. The region is also tightly packed with stars into what astronomers call a nuclear star cluster (NSC.) The combination of high speed and high stellar density creates a region where stars are bound to collide.

At the Kitt Peak National Observatory in Arizona, an instrument with 5,000 tiny robotic eyes scans the night sky. Every 20 minutes, the instrument and the telescope it’s attached to observe a new set of 5,000 galaxies. The instrument is called DESI—Dark Energy Survey Instrument—and once it’s completed its five-year mission, it’ll create the largest 3D map of the Universe ever created.

But scientists are getting access to DESI’s first data release and it suggests that dark energy may be evolving.

DESI is the most powerful multi-object survey spectrograph in the world, according to their website. It’s gathering the spectra for tens of millions of galaxies and quasars. The goal is a 3D map of the Universe that extends out to 11 billion light-years. That map will help explain how dark energy has driven the Universe’s expansion.

DESI began in 2021 and is a five-year mission. The first year of data has been released, and scientists with the project say that DESI has successfully measured the expansion of the Universe over the last 11 billion years with extreme precision.

“The DESI team has set a new standard for studies of large-scale structure in the Universe.”