Astronomy

Emerging AI services present scenarios that could challenge the laws over rights to a persona

Japan's Smart Lander for Investigating Moon (SLIM) mission failed to respond to a signal sent Monday — but all hope is not lost.

Mathematicians are working on ways to use their field to tackle major social issues, such as social inequality and the need for gender equity

Rocket Lab will launch the second of two cubesats for NASA's PREFIRE climate change mission tonight (May 31), and you can watch the action live.

Astronomers have detected giant, magnetic stars outside the Milky Way for the first time. These infant stars in the Magellanic Clouds could reveal details of early stellar evolution.

Week in images: 27-31 May 2024

Discover our week through the lens

NASA's new X-59 supersonic jet has successfully completed its Flight Readiness Review, marking a pivotal step towards its first flight.

The shape of the cosmos could be much more complex than anyone had ever imagined

Skin-care experts break down dangerous misconceptions about tanning and suggest healthy ways to enjoy summertime sunshine

Just watching someone scratch themselves on social media switches on the brain network that initiates the physical sensation of itch

The iconic star Polaris appears to be much younger than its true age. The secret: it’s eating another star

China's Chang'e 6 moon mission is studying landing sites on the lunar far side for accessibility ahead of a planned touchdown attempt this weekend.

A cost-effective pollution solution on Cape Cod could start in the bathroom.

There is an instant feel of quality in this rugged and easy-to-use Opticron Oregon 4 PC Oasis 10X42 monocular.

Arcturus and Vega highlight the evening, The Big Dipper quickly pivots. And sorry, tell your friends and family who ask that no "dazzling Parade of Planets" is blazing across the sky. Who makes this stuff up??

The post This Week's Sky at a Glance, May 31 – June 9 appeared first on Sky & Telescope.

Image: Resembling a reddish jellyfish, the Mahajamba Bay in Madagascar is imaged by Copernicus Sentinel-2.

Image: YPSat checked in for Ariane 6 flight

Lunar I-Hab, the next European habitat in lunar orbit as part of the Gateway, has recently undergone critical tests to explore and improve human living conditions inside the space module.

How can machine learning help astronomers find Earth-like exoplanets? This is what a recently accepted study to Astronomy & Astrophysics hopes to address as a team of international researchers investigated how a novel neural network-based algorithm could be used to detect Earth-like exoplanets using data from the radial velocity (RV) detection method. This study holds the potential to help astronomers develop more efficient methods in detecting Earth-like exoplanets, which are traditionally difficult to identify within RV data due to intense stellar activity from the host star.

The study notes, “Machine learning is one of the most efficient and successful tools to handle large amounts of data in the scientific field. Many algorithms based on machine learning have been proposed to mitigate stellar activity to better detect low-mass and/or long period planets. These algorithms can be classified into two categories: supervised learning and unsupervised learning. The advantage of supervised learning is that the proposed model contains a large set of variables and has the ability to produce relatively accurate predictions based on the training data.”

For the study, the researchers applied their algorithm to three stars to ascertain its ability to identify exoplanets within the stellar activity data: our Sun, Alpha Centauri B (HD 128621), and Tau ceti (HD 10700), with Alpha Centauri B being located approximately 4.3 light-years from Earth and Tau ceti being located approximately 12 light-years from Earth. After inserting simulated planetary signals within the algorithm, the researchers found their algorithm successfully identified simulated exoplanets with potential orbital periods ranging between 10 to 550 days for our Sun, 10 to 300 days for Alpha Centauri B, and 10 to 350 days for Tau ceti. It’s important to note that Alpha Centauri B currently has had several potential exoplanet detections but non confirmed while Tau ceti currently has eight exoplanets listed as “unconfirmed” within its system.

Additionally, the algorithm identified these results correspond to Alpha Centauri B and Tau ceti potentially having exoplanets approximately 4 times the size of Earth and within the habitable zones of those stars, as well. After inserting more stellar activity data into the algorithm, the researchers discovered the algorithm successfully identified a simulated exoplanet approximately 2.2 times the size of the Earth while orbiting the same distance as the Earth from our Sun.

The study noted in its conclusions, “In this paper, we developed a neural network framework to efficiently mitigate stellar activity at the spectral level, to enhance the detection of low-mass planets on periods from a few days up to a few hundred days, corresponding to the habitable zone of solar-type stars.”

While the study focused on finding Earth-like exoplanets within RV data, the researchers note that additional data, including transit time, phase, and space-based photometry, could be used to identify Earth-like exoplanets. They emphasize the European Space Agency’s PLATO space telescope mission could accomplish this, which is currently being developed and slated for launch sometime in 2026. Upon launch, it will be stationed at the Sun-Earth L2 Lagrange point located on the opposite side of the Earth from the Sun where it scan up to one million stars searching for exoplanets using the transit method with an emphasis on terrestrial (rocky) exoplanets.

PLATO mission discussed around the 9:00 mark

This study comes as the number of confirmed exoplanets by NASA has reached 5,632 as of this writing, which is comprised of 201 terrestrial exoplanets, and also provides the upcoming PLATO mission ample opportunity to discover many more terrestrial exoplanets within our Milky Way Galaxy.

How will machine learning help astronomers detect Earth-like exoplanets in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post A New Deep Learning Algorithm Can Find Earth 2.0 appeared first on Universe Today.

Universe Today has had the privilege of spending the last several months venturing into a multitude of scientific disciplines, including impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, planetary atmospheres, planetary geophysics, cosmochemistry, meteorites, radio astronomy, extremophiles, organic chemistry, and black holes, and their importance in helping teach scientists and the public about our place in the cosmos.

Here, we discuss the intriguing field of cryovolcanism with Dr. Rosaly Lopes, who is the Directorate Scientist for the Planetary Science Directorate and a Senior Research Scientist at NASA’s Jet Propulsion Laboratory, regarding the importance of studying cryovolcanism, examples throughout the solar system, what cryovolcanism can teach us about finding life beyond Earth, exciting aspects of studying cryovolcanism, and advice for upcoming students who wish to study cryovolcanism. So, what is the importance of studying cryovolcanism?

Dr. Lopes references Geissler (2015) and tells Universe Today, “My colleague Paul Geissler defined it well: ‘The eruption of liquid or vapor phases (with or without entrained solids) of water or other volatiles that would be frozen solid at the normal temperature of the icy satellite’s surface’.

While we associate volcanism on Earth as being when hot magma erupts from the Earth’s interior into a fiery blaze and melting everything in its path, cryovolcanism is the study of ice volcanism, as “cryo” is defined as “ice cold” or “frost”. The term was first used in an abstract at the 1987 Geological Society of America (GSA) Abstract with Programs by Steven K. Croft and has since been used to describe ice volcanoes throughout the solar system. Additional terms used in the context of cryovolcanism include cryomagma and cryolava—comparable to magma and lava from traditional volcanoes—and cryovolcanic edifice—comparable to traditional shield volcanoes seen both on Earth and other planetary bodies (i.e., Mars and Venus). Therefore, what are some examples of cryovolcanism in our solar system?

Dr. Lopes tells Universe Today, “We see active cryovolcanism on Enceladus, and signs of past cryovolcanism on Titan, Europa, Ganymede, and even Io (SO2 rather than water).” Dr. Lopes elaborates more on active and past volcanism in a 2010 book chapter, as well.

The reason we see active cryovolcanism on Saturn’s moon, Enceladus, is due to the large liquid water ocean it possesses beneath its icy crust, with NASA’s Cassini spacecraft having not only imaged active plumes erupting from Enceladus’ south pole “Tiger Stripes”, but Cassini also flew through the plumes in March 2008, using its Ion and Neutral Mass Spectrometer (INMS) to identify water vapor, carbon dioxide, carbon monoxide, and organic materials, whose levels were higher than the Cassini team had hypothesized prior to the flyby.

Saturn’s largest moon, Titan, is home to bodies of liquid methane and ethane across its surface due to the frigid surface temperatures of -182.55 degrees Celsius (-296.59 degrees Fahrenheit), whereas methane and ethane exist strictly as gases on Earth. Regarding evidence for past cryovolcanism on Titan, the Cassini spacecraft discovered Doom Mons in 2005 and Erebor Mons in 2007, with both currently being generally accepted as cryovolcanoes. Additionally, Cassini used its radar instruments in 2018 to identify topography on Titan that was identified as the “very best evidence” for a cryovolcano on Titan.

Like Enceladus, Jupiter’s two Galilean Moons, Europa and Ganymede, have exhibited significant evidence that they both contain interior liquid oceans beneath their icy crusts, and NASA’s Europa Clipper mission is slated to launch this October to explore this icy world in detail once it arrives sometime in 2030. Additionally, the European Space Agency’s Jupiter Icy Moons Explorer (JUICE) mission launched in April 2023 with the goal of studying Ganymede in detail and is currently scheduled to enter Ganymede’s orbit sometime in late 2034.

Regarding evidence of past cryovolcanism on Europa, scientists postulated in 2020 that plumes observed to emanate from Europa could originate from directly within the icy crust. For Ganymede, specific surface features known as paterae have indicated “potential cryovolcanic regions”, but scientists remain skeptical and have listed these features as something the JUICE mission should investigate further.

Additional worlds in our solar system that also exhibit past or current evidence of cryovolcanism include the dwarf planet, Ceres; Neptune’s moon, Triton; the dwarf planet, Pluto and its moon, Charon; and other dwarf planets, as well. Therefore, with this plethora of worlds that exhibit current or past evidence of cryovolcanism within our solar system, what can cryovolcanism teach us about finding life beyond Earth?

Dr. Lopes tells Universe Today, “For life as we know it to exist, we need water and energy – cryovolcanism provides the heat (energy) and it is a way to bring material that may have biosignatures to the surface of bodies. If the material just stays in the ocean under an ice crust, it could be many decades before we are able to sample it.”

Regarding the most exciting aspects about cryovolcanism that she has studied during her career, Dr. Lopes tells Universe Today, “Finding Doom Mons and Erebor Mons on Titan was very exciting, as they are the most convincing evidence we have that cryovolcanism happened on Titan.”

Like the other scientific disciplines that Universe Today has explored, the field of cryovolcanism involves the collaboration of scientists from a multitude of backgrounds, including volcanology, planetary geology, physics, and computer science. Through this, scientists can create computer models of cryovolcanism based on existing data, along with using imagery from orbiters to confirm or update their models to ascertain the processes behind the cryovolcanism they have observed. Therefore, what advice can Dr. Lopes offer upcoming students who wish to study cryovolcanism?

Dr. Lopes tells Universe Today, “The physics of the process is still not well understood. Lab experiments are valuable. They should read the literature and figure out how to advance their understanding.”

How will cryovolcanism teach us about our place in the universe in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Cryovolcanism: Why study it? What can it teach us about finding life beyond Earth? appeared first on Universe Today.