Science | WPN World People News

This infographic compares the characteristics of three classes of stars in our galaxy: Sunlike stars are classified as G stars; stars less massive and cooler than our Sun are K dwarfs; and even fainter and cooler stars are the reddish M dwarfs. The graphic compares the stars in terms of several important variables. The habitable zones, potentially capable of hosting life-bearing planets, are wider for hotter stars. The longevity for red dwarf M stars can exceed 100 billion years. K dwarf ages can range from 15 to 45 billion years. And, our Sun only lasts for 10 billion years. The relative amount of harmful radiation (to life as we know it) that stars emit can be 80 to 500 times more intense for M dwarfs relative to our Sun, but only 5 to 25 times more intense for the orange K dwarfs. Red dwarfs make up the bulk of the Milky Way's population, about 73%. Sunlike stars are merely 6% of the population, and K dwarfs are at 13%. When these four variables are balanced, the most suitable stars for potentially hosting advanced life forms are K dwarfs.

These images taken by the Terra satellite and enhanced by using correction reflectance bands on the MODIS (Moderation Resolution Imaging Spectroradiometer) highlight in brighter colors the areas on Kangaroo Island that have been burned by the bushfires in late December 2019 and early January 2020.

Conceptual image of water-bearing (left) and dry (right) exoplanets with oxygen-rich atmospheres. Crescents are other planets in the system, and the red sphere is the M-dwarf star around which the exoplanets orbit. The dry exoplanet is closer to the star, so the star appears larger.

TOI 1338 b is silhouetted by its host stars. TESS only detects transits from the larger star.

This new multiwavelength image of the Crab Nebula combines X-ray light from the Chandra X-ray Observatory (in blue) with visible light from the Hubble Space Telescope (in yellow) and infrared light seen by the Spitzer Space Telescope (in red). This particular combination of light from across the electromagnetic spectrum highlights the nested structure of the pulsar wind nebula. The X-rays reveal the beating heart of the Crab, the neutron-star remnant from the supernova explosion seen almost a thousand years ago. This neutron star is the super-dense collapsed core of an exploded star and is now a pulsar that rotates at a blistering rate of 30 times per second. A disk of X-ray-emitting material, spewing jets of high-energy particles perpendicular to the disk, surrounds the pulsar. The infrared light in this image shows synchrotron radiation, formed from streams of charged particles spiraling around the pulsar's strong magnetic fields. The visible light is emission from oxygen that has been heated by higher-energy (ultraviolet and X-ray) synchrotron radiation. The delicate tendrils seen in visible light form what astronomers call a "cage" around the rich tapestry of synchrotron radiation, which in turn encompasses the energetic fury of the X-ray disk and jets. These multiwavelength interconnected structures illustrate that the pulsar is the main energy source for the emission seen by all three telescopes. The Crab Nebula resides 6,500 light-years from Earth in the constellation Taurus.

This Hubble Space Telescope photograph showcases the majestic spiral galaxy UGC 2885, located 232 million light-years away in the northern constellation Perseus. The galaxy is 2.5 times wider than our Milky Way and contains 10 times as many stars. A number of foreground stars in our Milky Way can be seen in the image, identified by their diffraction spikes. The brightest star photobombs the galaxy's disk. The galaxy has been nicknamed "Rubin's galaxy," after astronomer Vera Rubin (1928 – 2016), who studied the galaxy's rotation rate in search of dark matter.

This figure shows the volcanic peak Idunn Mons (at 46 degrees south latitude, 214.5 degrees east longitude) in the Imdr Regio area of Venus. The colored overlay shows the heat patterns derived from surface brightness data collected by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS), aboard the European Space Agency's Venus Express spacecraft.

Hubble Sights Galaxy’s Celestial Sequins

An aerial view of Las Tintoreras, Isla Isabela in the Galapagos Islands, Ecuador.