Good Article: Understanding Rogue Planets

Posted on by onespaceman2000
Credit: Image by Dewald Van Rensburg from Pixabay.

Scientific American magazine has an interesting article on rogue planets, titled “How Many Rogue Planets Roam the Milky Way?” It discusses those lonely exoplanets that may or may not have started in a solar system, but nonetheless now drift in the darkness alone.

The article discusses a new paper from a team of astronomers at the Technion–Israel Institute of Technology that looked at the ejection of planets from planetary systems. Among the various findings noted, the team found that within the first billion years of a planetary system, on average as many as 3.5 planets are ejected , with most ejections happen within the first 100 million years. Moreover, systems with 10 or more planets eject more planets – as many as 70 percent of the system’s planets.

So that brings us back to our solar system. How many rogue planets did we spin off billions of years ago? We will never really know, but it gives one plenty to ponder when thinking about what awaits us out there should we venture beyond our present home system. Will we find old friends?

Note: An earlier article estimated there are seven rogue planets for every star in our galaxy, meaning the Milky Way may host trillions of rogue planets.

Protect NASA Astrobiology Research

Posted on by onespaceman2000
Image (Credit): Artist’s conception of a planetary lineup showing habitable-zone exoplanets with similarities to Earth, featured on the far right. (NASA/Ames/JPL-Caltech)

The astrobiology community is looking for individuals to show their support for NASA’s efforts in this area. In a white paper highlighting the benefits of astrobiology research, some of the key points are:

  • Preserve Astrobiology Leadership: Astrobiology is a pillar of NASA’s mission with a storied legacy that must be safeguarded.
  • Unprecedented Discoveries Ahead: Mars, Ocean Worlds, and exoplanet missions in the coming decades could finally answer one of humanity’s most profound questions: “are we alone?
  • Public Passion and Impact: The public passionately supports the search for life – a pursuit that inspires, unites, and advances STEM engagement.
  • NASA’s Unique Role: NASA’s unique capabilities and infrastructure position it as a leader in astrobiology, working in collaboration with U.S. academia and industry to advance this field.
  • Preserve Astrobiology at Its Peak: Astrobiology is thriving; workforce and research funding reductions must not derail our best chance to find life beyond Earth.

At a time of unprecedented threats to NASA’s program and mission, it is important to send a message to Congress and others that we have just begun to understand the universe and its potential for other forms of life, and now is not the time to back away.

The paper notes:

As NASA navigates the administration’s government-wide workforce optimization initiative, it is vital that we do not undermine astrobiology research – a field at the very heart of our agency’s purpose and future. Acting leadership has rightly stated that any reductions must align with mission needs. Few needs are more central to NASA’s science mission than understanding life’s existence beyond Earth.

The same site provides a link to an endorsement page.

I expect this is one of many initiatives to bring attention to the threats facing our space program. It is true that some efficiencies can be found in government with the right level of analysis and careful consideration of existing programs (as has been done in the past), but that is not happening right now with the random and unexplainable cuts.

Space Stories: JWST Exoplanet Images, Nearby Exoplanets Located, and Exoplanet Biosignatures,

Posted on by onespaceman2000
Image (Credit): Infrared view of the multi-planet system HR 8799. Colors are applied to filters from Webb’s NIRCam (Near-Infrared Camera). A star symbol marks the location of the host star HR 8799, whose light has been blocked by the coronagraph. (NASA, ESA, CSA, STScI, W. Balmer (JHU), L. Pueyo (STScI), M. Perrin (STScI))

Here are some recent stories of interest related to exoplanets.

—Webbtelescope.org: “NASA’s Webb Images Young, Giant Exoplanets, Detects Carbon Dioxide“

The first planet outside our solar system was discovered in the 1990’s, but it wasn’t until more than a decade later astronomers actually obtained a direct image of one. It’s extremely difficult to image an exoplanet, as stars in other planetary systems can be thousands of times brighter and bigger than their planets. NASA’s James Webb Space Telescope is equipped with a highly sensitive coronagraph, a tiny mask that blocks the light of the star, allowing Webb to image exoplanets. Webb’s new images of two iconic systems, HR 8799 and 51 Eridani, and their planets have stunned researchers, and provided additional information into the chemical make-up of the young gas giants.

—ABC News: “Several Planets Found Orbiting Star Less Than 6 light-years Away“

Astronomers have confirmed the existence of four planets orbiting a star less than 6 light-years away with help from some of the world’s most powerful telescopes. Research published in October 2024 revealed that one planet was rotating around Barnard’s Star, the second-closest single star system to Earth. But a combination of telescopes all over the world confirmed the presence of four small exoplanets, according to a study published last week in The Astrophysical Journal Letters.

—Universe Today: “Astronomers Think They’ve Found a Reliable Biosignature. But There’s a Catch“

The search for life has become one of the holy grails of science. With the increasing number of exoplanet discoveries, astronomers are hunting for a chemical that can only be present in the atmosphere of a planet with life! A new paper suggests that methyl halides, which contain one carbon and three hydrogen atoms, may just do the trick. Here on Earth they are produced by bacteria, algae, fungi and some plants but not by any abiotic, non biological processes. There is a hitch, detecting these chemicals is beyond the reach of current telescopes.

Space Stories: Upcoming ESA Exoplanet Mission, Evidence of Early Water in the Universe, and a New Nearby Dwarf Galaxy

Posted on by onespaceman2000

Here are some recent stories of interest.

—German Aerospace Center: “PLATO Mission to Launch in Late 2026 Onboard Ariane 6“

On 29 January 2025, the European Space Agency (ESA)’s Director of Science, Carole Mundell; ESA’s Director of Space Transportation, Toni Tolker-Nielsen; and Arianespace’s Chief Commercial Officer, Steven Rutgers, signed the launch contract for the ESA PLATO science mission...PLATO stands for PLAnetary Transits and Oscillations of stars…PLATO’s goal is to detect Earth-like planets that orbit Sun-like stars in the Milky Way and may even have conditions suitable for life.

—ScienceNews: “The Universe’s First Supernovas Probably Produced Water“

The first generation of stars in the universe could have produced significant amounts of water upon their deaths, just 100 million to 200 million years after the Big Bang. Signatures of water have previously been observed some 780 million years after the Big Bang. But now, computer simulations suggest that this essential condition for life existed far earlier than astronomers thought, researchers report March 3 in Nature Astronomy.

—Phys.org: “New Dwarf Galaxy Discovered in the Halo of Andromeda Galaxy“

An international team of astronomers reports the discovery of a new dwarf galaxy, which they have named Pegasus VII. The newfound galaxy, which lies about 2.4 million light years away, was identified in the Ultraviolet Near-Infrared Optical Northern Survey (UNIONS). The discovery was detailed in a research paper published Feb. 13 on the arXiv preprint server. Dwarf galaxies are low-luminosity and low-mass stellar systems, usually containing a few billion stars. Their formation and activity are thought to be heavily influenced by interactions with larger galaxies.

Space Stories: Solar Orbiter Encounters Venus, White Dwarf Exoplanets, and the End of Gaia

Posted on by onespaceman2000
Credit: ESA

Here are some recent stories of interest..

—European Space Agency: “Solar Orbiter Ready for Close Encounter with Venus’“

The European Space Agency (ESA) is ready to guide the ESA/NASA Solar Orbiter spacecraft through its closest encounter with Venus so far. Today’s flyby will be the first to significantly ‘tilt’ the spacecraft’s orbit and allow it to see the Sun’s polar regions, which cannot be seen from Earth. Studying the Sun’s poles will improve our understanding of solar activity, space weather, and the Sun-Earth connection.

—UC Irvine News: “UC Irvine Astronomers Gauge Livability of Exoplanets Orbiting White Dwarf Stars’“

Among the roughly 10 billion white dwarf stars in the Milky Way galaxy, a greater number than previously expected could provide a stellar environment hospitable to life-supporting exoplanets, according to astronomers at the University of California, Irvine. In a paper published recently in The Astrophysical Journal, a research team led by Aomawa Shields, UC Irvine associate professor of physics and astronomy, share the results of a study comparing the climates of exoplanets at two different stars. One is a hypothetical white dwarf that’s passed through much of its life cycle and is on a slow path to stellar death. The other subject is Kepler-62, a “main sequence” star at a similar phase in its evolution as our sun.

—Uppsala University: “Mission Accomplished for Space Telescope Gaia’“

The space telescope Gaia has created the largest three-dimensional map of the Milky Way ever. On January 15, 2025, Gaia shut down after 11 years in space. But the research on data Gaia collected will continue for many years to come. Gaia is a space telescope onboard a satellite that has orbited the sun for 11 years. With the help of astrometry, which is a technique to measure the positions, distances and movements of stars and other heavenly bodies, Gaia has been able to measure distances and luminosities for up to 2 billion stars, which is about 1% of all stars in the Milky Way.