Universe Today

September 17, 2024September 17, 2024 by Mark Thompson

Earth Might Have Had Rings Half a Billion Years Ago

Areas of continental crust proximal to the equator during the Ordovician

Saturn is well known for its ring system and many recognise that the planets Jupiter, Uranus and Neptune also have rings. Did Earth ever have rings though? A team of researchers suggests that a worldwide collection of impact craters points to the existence of a ring around Earth millions of years ago. It’s possible that Earth captured and destroyed an asteroid that passed too close 466 million years ago. The asteroids torn up debris orbited the Earth as a ring and then the individual chunks entered the atmosphere, landed on the surface and produced the craters observed today.

September 17, 2024September 17, 2024 by Mark Thompson

Earth Will Have a Tiny New Mini-Moon for a Few Months

An illustration of a completely unrelated asteroid

The Moon has inspired poets and artists, musicians and playwrights. The sight of our one and only Moon is familiar to anyone that has ever glanced up at the night time (and sometimes day time sky!) Every so often though, our Moon (note the use of capital ‘M’)is joined by a small asteroid that wanders too close. Astronomers have detected an 11-metre wide asteroid that has the snappy name 2024 PT5 and it came within 567,000 kilometres of Earth and will become a temporary satellite from 29 September until 25 November when it will leave our system.

September 16, 2024September 16, 2024 by Evan Gough

A Black Hole has Almost Halted Star Formation in its Galaxy

This is a quiescent galaxy in the early Universe named GS-10578 but nicknamed ‘Pablo’s Galaxy’. It has an SMBH in its center, and astronomers have used the NASA/ESA James Webb Space Telescope to confirm that supermassive black holes can starve their host galaxies of the fuel they need to form new stars. Image Credit: JADES Collaboration

When the James Webb Space Telescope was launched on Christmas Day in 2021, it faced a whole host of intriguing questions. By the time it finally launched, astronomers had a big list of targets begging for the type of detailed observations that only the powerful infrared space telescope could perform. One of the targets was an ancient, massive galaxy that’s basically dead and forms no new stars.

The results are in, and an international team of astronomers know what happened to the quiescent galaxy.

September 16, 2024September 16, 2024 by Andy Tomaswick

An Ambitious Mission to Neptune Could Study Both the Planet and Triton

Mission concepts to the outer solar system are relatively common, as planetary scientists are increasingly frustrated by our lack of knowledge of the farthest planets. Neptune, the farthest known planet, was last visited by Voyager 2 in the 1980s. Technologies have advanced a lot since that probe was launched in 1977. But to utilize that better technology, we first need to have a mission arrive in the system – and one such mission is being developed over a series of papers by ConEx Research and University College London.

September 16, 2024September 17, 2024 by David Dickinson

Earth’s Shadow Nicks the Moon During This Week’s Partial Lunar Eclipse

The Moon just brushes the umbral shadow of the Earth during Tuesday night’s partial lunar eclipse.

A shallow partial lunar eclipse is on tap for the night of September 17th/18th. The eclipse is a slight one to be sure, but will be noticeable as the northwestern limb of the Moon just slips past the dark inner umbral shadow of the Earth. The eclipse is just over 8% partial at its maximum, meaning the Full Moon will look a little ‘smushed’ on one side at mid-eclipse.

September 16, 2024September 16, 2024 by Mark Thompson

Mars has an Amazing Variety of Clouds

Lee waves: Lee waves are a special type of cloud created by the wind encountering obstacles and build up on the ‘leeward‘ or downwind side. The geometries of the lee waves depend on the shape of the obstacles. Credit: ESA/DLR/FU Berlin.

Mars has always held a special place in our hearts, likely from hints over the decades of perhaps finding signs of life, albeit fossilised and primitive. It’s been the subject of study from telescopes and space missions alike, most notably ESA’s Mars Express which has been observing the red planet for 20 years. Over the two decades of observation it has studied an amazing variety of atmospheric phenomenon which have now been catalogued in a new ‘Cloud Atlas.’ Many will be familiar to sky watchers on Earth but some are very different.

September 15, 2024September 15, 2024 by Andy Tomaswick

Can a Greenhouse with a Robotic Arm Feed the Next Lunar Astronauts?

Continuous human habitation of the Moon is the state aim of many major space-faring nations in the coming decades. Reaching that aim requires many tasks, but one of the most fundamental is feeding those humans. Shipping food consistently from Earth will likely be prohibitively expensive shortly, so DLR, Germany’s space agency, is working on an alternative. This semi-autonomous greenhouse can be used to at least partially feed the astronauts in residence on the Moon. To support that goal, a team of researchers from DLR released a paper about EVE, a robotic arm intended to help automate the operations of the first lunar greenhouse, at the IEEE Aerospace conference in March.

September 15, 2024September 15, 2024 by Matt Williams

Early Dark Energy Could Resolve Two of the Biggest Mysteries in Cosmology

This is a small portion of the field observed by NASA’s James Webb Space Telescope’s NIRCam (Near-Infrared Camera) for the Cosmic Evolution Early Release Science (CEERS) survey. It is filled with galaxies. The light from some of them has traveled for over 13 billion years to reach the telescope. Credit: NASA, ESA, CSA, Steve Finkelstein (University of Texas at Austin)

Of all the mysteries facing astronomers and cosmologists today, the “Hubble Tension” remains persistent! This term refers to the apparent inconsistency of the Universe’s expansion (aka. the Hubble Constant) when local measurements are compared to those of the Cosmic Microwave Background (CMB). Astronomers hoped that observations of the earliest galaxies in the Universe by the James Webb Space Telescope (JWST) would solve this mystery. Unfortunately, Webb confirmed that the previous measurements were correct, so the “tension” endures.

Since the JWST made its observations, numerous scientists have suggested that the existence of Early Dark Energy (EDE) might explain the Hubble Tension. In a recent study supported by NASA and the National Science Foundation (NSF), researchers from the Massachusetts Institute of Technology (MIT) suggested that EDE could resolve two cosmological mysteries. In addition to the Hubble Tension, it might explain why Webb observed as many galaxies as it did during the early Universe. According to current cosmological models, the Universe should have been much less populated at the time.

September 15, 2024September 15, 2024 by Laurence Tognetti

Studying Stars from the Lunar Surface with MoonLITE, Courtesy of NASA’s Commercial Lunar Payload Services

Diagram conveying the setup for MoonLITE on the lunar surface, beginning with a lander being delivered by NASA’s Commercial Lunar Payload Services (1), which unrolls a fiber umbilical over 100 meters (328 feet) (2), concluding with deploying the siderostat station (3). Science operations begin once instrument calibration is performed. (Credit: van Belle et al. (2024))

Optical interferometry has been a long-proven science method that involves using several separate telescopes to act as one big telescope, thus achieving more accurate data as opposed to each telescope working individually. However, the Earth’s chaotic atmosphere often makes achieving ground-based science difficult, but what if we could do it on the Moon? This is what a recent study presented at the SPIE Astronomical Telescopes + Instrumentation 2024 hopes to address as a team of researchers propose MoonLITE (Lunar InTerferometry Explorer) as part of the NASA Astrophysics Pioneers program. This also comes after this same team of researchers recently proposed the Big Fringe Telescope (BFT), which is a 2.2-kilometer interferometer telescope to be built on the Earth with the goal of observing bright stars.

September 14, 2024September 14, 2024 by Matt Williams

New Video Shows How Tiny Spacecraft Will “Swarm” Proxima Centauri

Screenshot of the animation showing the Swarming Proxima Centauri approaching Proxima b. Credit: i4is/Interstellar Initiatives

Earlier this year, NASA selected a rather interesting proposal for Phase I development as part of their NASA Innovative Advanced Concepts (NIAC) program. It’s known as Swarming Proxima Centauri, a collaborative effort between Space Initiatives Inc. and the Initiative for Interstellar Studies (i4is) led by Space Initiative’s chief scientist, Marshall Eubanks. The concept was recently selected for Phase I development as part of this year’s NASA Innovative Advanced Concepts (NIAC) program.

Similar to other proposals involving gram-scale spacecraft and lightsails, the “swarming” concept involves accelerating tiny spacecraft with a laser array to up to 20% the speed of light. This past week, on the last day of the 2024 NASA Innovative Advanced Concepts (NIAC) Symposium, Eubanks and his colleagues presented an animation illustrating what this mission will look like. The video and their presentation provide tantalizing clues as to what scientists expect to find in the closest star system to our own. This includes Proxima b, the rocky planet that orbits within its parent star’s circumsolar habitable zone (CHZ).