Astronomy

A subsurface ocean of liquid water may exist beneath Pluto's nitrogen ice, according to an analysis of data collected by NASA's New Horizons probe.

The stars of Star Trek are about to get a taste of real-life space exploration when they beam into the 2024 International Space Development Conference in Los Angeles this weekend.

China launched four satellites on Tuesday (May 21) to test out new technologies. The spacecraft went up on the third-ever launch of the Kuaizhou-11 solid rocket.

The Universe wants us to understand its origins. Every second of every day, it sends us a multitude of signals, each one a clue to a different aspect of the cosmos. But the Universe is the original Trickster, and its multitude of signals is an almost unrecognizable cacophony of light, warped, shifted, and stretched during its long journey through the expanding Universe.

What are talking apes to do in this situation but build another telescope adept at understanding a particular slice of all this noisy light? That’s what astronomers think we should do, to nobody’s surprise.

Due to the size of the Universe and its ongoing expansion, light from the Universe’s first galaxies is stretched into the infrared. This ancient light holds clues to the Universe’s origins and, by extension, our origins. It takes a powerful infrared telescope to sense and decipher this light. Earth’s atmosphere blocks infrared light which is why we keep building infrared space telescopes.

Infrared telescopes are also well-suited to observing planets as they form. Dense environments like protoplanetary disks are opaque to most light, but infrared light can reveal what’s going on in these planet-forming environments. The dust absorbs light, then emits it in the infrared, and also scatters it. That confounds optical telescopes, but infrared telescopes like SALTUS are designed to deal with it.

A team of astronomers from the USA and Europe has joined the chorus calling for a new infrared space telescope. It’s tentatively called SALTUS, the Single Aperture Large Telescope for Universe Studies. In a new paper, the astronomers outline the science case for SALTUS.

“The SALTUS Probe mission will provide a powerful far-infrared (far-IR) pointed space observatory to explore our cosmic origins and the possibility of life elsewhere,” write the authors of the new paper.

The paper is titled “Single Aperture Large Telescope for Universe Studies (SALTUS): Science Overview.” Gordon Chin from NASA’s Goddard Space Flight Center is the lead author. It’s in pre-print at arxiv.org.

If built, SALTUS will be different from the powerful JWST. The JWST has four instruments that cover an infrared frequency range from 600 to 28,500 nanometers, or 0.6 to 28.5 microns, which is from the near-infrared (NIR) to the mid-infrared (MIR). SALTUS would cover 34 to 660 ?m, which is in the far-infrared (FIR). SALTUS’ range is unavailable to any current observatory, space or ground-based.

There are no precise definitions of what exact ranges constitute NIR, MIR, and FIR, but this table is a useful representation. Image Credit: Wikipedia

Infrared telescopes need to be kept cool. They use sunshades and cryogenic coolers to keep temperatures down and IR light detectable. The longer the wave of infrared light, the cooler the sensor needs to be. Sunshades are passive and cool the primary mirror, but the instruments require active cryogenic cooling, and those systems have a limited lifetime that restricts mission length. In SALTUS’s case, the baseline mission length is five years.

During those five years, SALTUS will make use of its 14-meter primary mirror and its pair of instruments to open a “powerful window to the Universe through which we can explore our cosmic origins,” according to the paper’s authors.

The two instruments are the SAFARI-Lite spectrometer (SALTUS Far-Infrared Lite) and HiRX (High-Resolution receiver.) Using these instruments, SALTUS will complement the observing capabilities of the JWST and ALMA, the Atacama Large Millimetre/submillimetre Array.

Its aperture is so large that it’ll be the only Far-IR observatory with arcsec-scale spatial resolution. One arcsecond is defined as the ability to show two posts standing 4.8mm apart from 1km away as separate posts. “This will permit an unmasking of the true nature of the cold Universe, which holds the answers to many of the questions concerning our cosmic origins,” the authors write.

SALTUS has a unique design among space telescopes. It features an inflatable primary mirror, which is new to space telescopes but has been proven during decades of use in ground-based telecommunications. A two-layer sunshield will keep the inflatable mirror cool.

SALTUS large aperture will provide high sensitivity and is aimed at a couple of foundational questions.

How does habitability develop while planets are forming? To address this question, SALTUS will trace carbon, oxygen, and nitrogen in 1,000 different protoplanetary disks. It has the power to recognize numerous molecular and atomic species and different lattice modes of ice and some minerals. No existing telescope has this capability.

SALTUS’ far IR observing capabilities will let it see a portion of protoplanetary disks that are obscured in other wavelengths. This will open a new window into planet formation and how habitability develops. Image Credit: Chin et al. 2025/Miotello et al. Protostars and Planets 2023.

Habitability, as far as we understand it, revolves around water. Water begins its journey in the same molecular clouds where stars form. SALTUS will follow water’s journey from molecular cloud to protoplanetary disks to icy planetesimals and comets that deliver water to planets like Earth. A key part of SALTUS’s work will be deriving deuterium/hydrogen ratios.

This simple graphic shows how water arrives on planets and can lead to habitability. SALTUS will follow the water’s journey by observing hundreds of protoplanetary disks. Image Credit: Chin et al. 2024.

How do galaxies form and evolve? SALTUS will measure how galaxies form and acquire more mass. It’ll measure heavy elements and interstellar dust from the Universe’s first galaxies to today. The telescope will also probe the co-evolution of galaxies and their supermassive black holes (SMBHs.)

Tracking the rapid evolution of dust grains in galaxies in the Universe’s first billion years is part of understanding galaxy formation and evolution. SALTUS can do that by observing PAHs, polycyclic aromatic hydrocarbons, and their spectral lines. Some PAH spectral lines are very faint but entirely visible to SALTUS.

There’s a causal link between star formation and active galactic nuclei (AGN) that influences galaxy growth and evolution. But the two phenomena take place on wildly different spatial scales, and the phase that links them together is obscured by dust. SALTUS’s high resolution and sensitive far-IR spectroscopy will give astronomers a clearer view of AGN and how they shape galaxies.

SALTUS would be placed into a Sun-Earth Halo L2 orbit. Its maximum distance from Earth would be 1.8 million km (1.12 million miles). That orbit would give the telescope two continuous 20º viewing zones around the ecliptic poles, resulting in full sky coverage every six months.

The SALTUS concept is designed in response to the 2020 Decadal Survey and NASA’s Astrophysical Roadmap. It’s a direct response to NASA’s 2023 Astrophysics Probe Explorer (APEX) solicitation. The questions it’ll help answer come directly from those works.

“SALTUS has both the sensitivity and spatial resolution to address not just the open science questions of the year 2023 but, more importantly, the unknown questions that will be raised in the 2030s,” the authors write in their summary. “SALTUS is forward-leaning and well-suited to serving the current and future needs of the astronomical community.”

The post Astronomers Propose a 14-Meter Infrared Space Telescope appeared first on Universe Today.

This year could bring up to 25 named tropical storms in the Atlantic Ocean due to a shift to La Niña conditions, says the US National Oceanic and Atmospheric Administration

This year could bring up to 25 named tropical storms in the Atlantic Ocean due to a shift to La Niña conditions, says the US National Oceanic and Atmospheric Administration

Male mice injected with a molecule that affects sperm movement were temporarily unable to impregnate a female, showing promise for a new type of birth control drug for people

Male mice injected with a molecule that affects sperm movement were temporarily unable to impregnate a female, showing promise for a new type of birth control drug for people

A twice-flown SpaceX capsule has debuted at the Griffin Museum of Science and Industry in Chicago, next to a Mercury spacecraft and an Apollo command module.

Detecting bird flu signs in dairy cows sooner could have helped staunch the virus's spread

The ICEYE satellite constellation has given researchers a peek beneath the glacier, and it's not looking good.

The parade of interesting new exoplanets continues. Today, NASA issued a press release announcing the discovery of a new exoplanet in the Gliese 12 system, sized somewhere between Earth and Venus and inside the host star’s habitable zone. Two papers detail the discovery, but both teams think that the planet is an excellent candidate for follow-up with the James Webb Space Telescope (JWST) to try to tease out whether it has an atmosphere and, if so, what that atmosphere is made of.

But before JWST knew where to look, another workhorse of the exoplanet hunt had to do its job. The Transiting Exoplanet Survey Satellite (TESS) found this planet in a system only 40 light years away. That would make it the closest known example of a rocky, Earth or Venus-sized exoplanet in its star’s habitable zone.

Gliese 12 is a red dwarf, only weighing about 27% of the Sun’s weight. Due to the intricacies of fusion, this amounts to the star outputting about 60% of the light of our Sun, which, in turn, means its habitable zone is much closer than our own. The planet, known as Gliese 12b, orbits its parent star once every 12.8 days. But more importantly, it receives about 85% of the energy that Venus typically receives from the Sun.

Fraser discusses some of the accomplishments of TESS.

The similarity between our closest neighbor and this exoplanet is striking. It could also lead to new discoveries about the formation of our solar system. Current theory holds that Venus and the Earth originally had an atmosphere and then lost it. They diverged to become the Eden-like Earth and the hell-like Venus because of one crucial substance – water.  

Venus’ atmosphere lacked water, so when its current atmosphere started to form, none of the liquid necessary for life as we know it was available. Earth, on the other hand, had plenty of water to spare, allowing it to eventually develop life and humans to evolve there.

One of the holy grails of astrobiology is to find an Earth analog, where the solar radiation, day length, size, atmospheric makeup, and other factors are similar enough for a reasonable chance for life to evolve. We can quickly determine many of those numbers, such as orbit, size, and the amount of solar radiation a planet receives. But finding details like atmospheric makeup is harder.

Artist’s depiction of Gliese 12b in comparison to Earth, with different atmospheres – from no atmosphere at all on the left to a atmosphere like Venus’ on the right.
Credit – NASA / JPL-Caltech/R. Hurt (Caltech/IPC)

Hence why the researchers suggested JWST should get involved. The world’s most powerful space-based telescope would be capable of detecting the atmospheric makeup of Gliese 12b using a technique called transmission spectroscopy. That’s when the light from a planet’s host star is forced through the planet’s atmosphere, and what wavelengths are absorbed can give an astronomer an idea of what kind of gases are present in that atmosphere.

For now, it’s pure speculation whether Gliese12b has any atmosphere. But with some observational time on JWST, scientists should be able to answer that question easily. Until then, workhorses like TESS will keep picking up new exoplanet candidates for JWST to look at. There are undoubtedly some more interesting ones hiding out there amongst the stars—it’s only a matter of time before we find them.

Learn More:
Kuzuhara et al. – Gliese 12 b: A Temperate Earth-sized Planet at 12 pc Ideal for Atmospheric Transmission Spectroscopy
Dholakia et al.- Gliese 12 b, a temperate Earth-sized planet at 12 parsecs discovered with TESS and CHEOPS
UT – TESS Finds Eight More Super-Earths
UT – Hubble Succeeds Where TESS Couldn’t: It Measured the Nearest Transiting Earth-Sized Planet

Lead Image:
Artist’s depiction of Gliese 12b and its parent star.
Credit – NASA / JPL-Caltech / R Hurt (Caltech-IPAC)

The post A New Venus-Sized World Found in the Habitable Zone of its Star appeared first on Universe Today.

Counting crows proclaim “caw, caw, caw, caw” when staring at the number four

SpaceX launched 23 more of its Starlink internet satellites from Florida on Thursday night (May 23). It was the third mission in two days for the company.

NASA astronaut Kate Rubins places a sample marker in the soil before collecting a sample during a nighttime simulated moonwalk in the San Francisco Volcanic Field in Northern Arizona on May 16, 2024. A sample marker provides a photographic reference point for science samples collected on the lunar surface.

NASA exoplanet-hunter TESS has found a temperate, Earth-size world in the habitable zone of its red dwarf star. This planet could make waves in the search for life.

Supermassive black holes that are blasting out beams of high-energy particles killing star formation in their galaxies are shifting targets like real-life Death Stars.

Electric trucks and sedans have proven popular with municipal fleets, but cities have also bought niche vehicles such as an electric Zamboni

The Holy Stone HS900 adds another attractive option in the sub-250g drone category thanks to great flight performance.

A dose of caffeine helped ants locate a sweet reward 30 per cent faster, suggesting the drug boosts learning in the insects