Universe Today

December 9, 2024December 9, 2024 by Brian Koberlein

Do We Really Know What Becomes a Type Ia Supernova?

Illustration of a Type Ia supernova. Credit: Kiso Observatory, The University of Tokyo

Lots of things out in the Universe can cause a supernova, from the gravitational collapse of a massive star, to the collision of white dwarfs. But most of the supernovae we observe are in other galaxies, too distant for us to see the details of the process. So, instead, we categorize supernovae by observed characteristics such as the light curves of how they brighten and fade and the types of elements identified in their spectra. While this gives us some idea of the underlying cause, there are still things we don’t entirely understand. This is particularly true for one particular kind of supernova known as Type Ia.

December 9, 2024December 9, 2024 by Andy Tomaswick

A Cheap Satellite with Large Fuel Tank Could Scout For Interplanetary Missions

A spacecraft that can provide the propulsion necessary to reach other planets while also being reproducible, relatively light, and inexpensive would be a great boon to larger missions in the inner solar system. Micocosm, Inc., based in Hawthorne, California, proposed just such a system via a NASA Small Business Innovation Research (SBIR) grant. Its Hummingbird spacecraft would have provided a platform to visit nearby planets and asteroids and a payload to do some basic scouting of them.

December 9, 2024December 11, 2024 by David Dickinson

Our Strategy to Catch the 2024 Geminid Meteors

Don’t let the bright Moon deter you from seeing the one of the best meteor showers of the year.

Update: Astronomer Gianluca Masi will carry the Geminid meteors live on December 13th, courtesy of the Virtual Telescope Project.

One of the best meteor showers of 2024 closes out the year this coming weekend. If skies are clear, watch for the Geminid meteors, peaking on the night of Friday into Saturday, December 13-14^th.

December 8, 2024December 8, 2024 by Brian Koberlein

Observations by DESI Open the Door to Modified Gravity Models

The relations between various approaches of modified gravity. Credit: J. M. Ezquiaga and M. Zumalacárregui (2018)

The standard theory of cosmology is based upon four things: the structure of space and time, matter, dark matter, and dark energy. Of these, dark energy is the one we currently understand the least. Within the standard model, dark energy is part of the structure of space and time as described by general relativity. It is uniform throughout the cosmos and expressed as a parameter known as the cosmological constant. But initial observations from the Dark Energy Spectroscopic Instrument (DESI) suggest the rate of comic expansion may vary over time. If further observations reinforce this, it could open up cosmological models to alternatives to general relativity known as modified gravity.

December 8, 2024December 8, 2024 by Mark Thompson

Using Jupiter as a Dark Matter Detector

This full-disc image of Jupiter was taken on 21 April 2014 with Hubble's Wide Field Camera 3 (WFC3).

The nature of dark matter has been a hotly debated topic for decades. If it’s a heavy, slow moving particle then it’s just possible that neutrinos may be emitted during interactions with normal matter. A new paper proposes that Jupiter may be the place to watch this happen. It has enough gravity to capture dark matter particles which may be detectable using a water Cherenkov detector. The researchers suggest using a water Cherenkov detector to watch for excess neutrinos coming from the direction of Jupiter with energies between 100 MeV and 5 GeV.

December 7, 2024December 7, 2024 by Matt Williams

NASA has Plans for More Cargo Deliveries to the Moon

Early conceptual renderings of cargo variants of human lunar landing systems from NASA’s providers SpaceX, left, and Blue Origin, right. Credit: SpaceX/Blue Origin

Through the Artemis Program, NASA hopes to lay the foundations for a program of “sustained lunar exploration and development.” This will include regular missions to the surface, the creation of infrastructure and habitats, and a long-term human presence. To facilitate this, NASA is teaming up with industry and international partners to develop Human Landing Systems (HLS) that can transport crews to and from the lunar surface and landers that can deliver payloads of equipment, vehicles, and supplies to the lunar surface.

In a recent statement, NASA indicated that it intends to award Blue Origin and SpaceX additional work under their existing contracts to develop landers that will deliver equipment and infrastructure to the lunar surface. NASA also plans to assign demonstration missions to these companies, in addition to design certification reviews, which will validate their concepts. This decision builds on NASA’s earlier request, made in 2023, that the two companies develop cargo versions of their HLS concepts, which are currently in development for the Artemis III, Artemis IV, and Artemis V missions.

December 7, 2024December 7, 2024 by Scott Alan Johnston

Space Telescopes Could See a Second Life With a Servicing Mission

CAD model of the Gaia spacecraft with service vehicle, post-docking configuration.

Telescopes in space have a huge advantage over those on the ground: they can see the universe more clearly. The Earth’s atmosphere, weather conditions, and low-flying satellites don’t obscure their view. But space telescopes have a disadvantage too. They can’t be repaired, at least not since NASA’s Space Shuttle program ended in 2011.

But next-generation telescopes are being planned with robotic servicing missions in mind. And not just in low earth orbit, where the Hubble Space Telescope received repairs and upgrades five times during its lifespan from space shuttle crews. Today’s engineers are preparing for ways to repair telescopes in deep space, including at the Sun-Earth Lagrange point L2.

December 6, 2024December 6, 2024 by Mark Thompson

Other Liquids Could Be Forming Minerals on Mars

At left: Steel is seen to corrode into siderite (FeCO3) when immersed in subcritical liquid carbon dioxide (LCO2). At right: Samples of albite (a plagioclase feldspar) and a sandstone core are observed to form red rhodochrosite (MnCO3) when exposed to supercritical CO2 in the presence of a water solution with potassium chloride and manganese chloride, with particularly strong reaction near the interface of the two solutions. In both experiments, water saturation is provided by floating LCO2 on the water. Under the lower pressure conditions characteristic of early Mars, the water would float on the LCO2. Credits:Photos courtesy of Todd Schaef/PNNL (left) and Earl Mattson/Mattson Hydrology (right).

Most people will think of a dry arid landscape when they think of Mars. When seen from orbit, dry river channels and lake-beds can be seen along with mineral deposits thought to be the created in the presence of liquid water. A team of researches now suggest that liquid carbon dioxide could also explain the features seen. On Earth, a process known as carbon sequestration liquefies CO2 which is buried underground. There are a number of mechanisms that could explain the liquid CO2 underground the researchers suggest.

December 6, 2024December 6, 2024 by Mark Thompson

Jared Isaacman is Trump’s Choice for NASA Administrator

As a new President of the United States is elected, the NASA administrator role is usually reviewed. With the election of Trump, a new administrator has been chosen, Jared Isaacman. He is a billionaire entrepreneur, an experienced jet pilot and has himself completed to private flights to space. He was also the first to complete a spacewalk during the Polaris Dawn mission. Isaacman replaces the outgoing administrator Bill Nelson, a former space shuttle astronaut and senator.

December 6, 2024December 6, 2024 by Carolyn Collins Petersen

NASA Pushes Human Moon Landing Back to 2027

Artist's rendering of the Starship HLS on the lunar surface. NASA has contracted with SpaceX to provide the lunar landing system. Credit: SpaceX — Artist's rendering of the Starship HLS on the Moon's surface. NASA has contracted with SpaceX to provide the lunar landing system. Credit: SpaceX

The Artemis moon landings are delayed again due to technical difficulties. This time, the problem is with the Orion spacecraft heat shield. NASA administrator Bill Nelson announced that the new landing dates are in April of 2026 for Artemis II and sometime in 2027 for the first human landing during the Artemis III mission.