Scattered stars in Sagittarius

This colourful and star-studded view of the Milky Way galaxy was captured when the NASA/ESA Hubble Space Telescope pointed its cameras towards the constellation of Sagittarius (The Archer). Blue stars can be seen scattered across the frame, set against a distant backdrop of red-hued cosmic companions. This blue litter most likely formed at the same time from the same collapsing molecular cloud.

The colour of a star can reveal many of its secrets. Shades of red indicate a star much cooler than the Sun, so either at the end of its life, or much less massive. These lower-mass stars are called red dwarfs and are thought to be the most common type of star within the Milky Way. Similarly, brilliant blue hues indicate hot, young, or massive stars, many times the mass of the Sun.

A star's mass decides its fate; more massive stars burn brightly over a short lifespan, and die young after only tens of millions of years. Stars like the Sun typically have more sedentary lifestyles and live longer, burning for approximately ten billion years. Smaller stars, on the other hand, live life in the slow lane and are predicted to exist for trillions of years, well beyond the current age of the Universe.

Credit: ESA/Hubble & NASA

Comments

Fermi Bubbles

Image: A giant gamma-ray structure was discovered in 2010 by processing Fermi all-sky data at energies from 1 to 10 billion electron volts, shown here. The dumbbell-shaped feature (center) emerges from the galactic center and extends 50 degrees north and south from the plane of the Milky Way, spanning the sky from the constellation Virgo to the constellation Grus. Credits: NASA/DOE/Fermi LAT/D. Finkbeiner et al. At a time when our earliest human ancestors mastered walking upright the heart of our Milky Way galaxy underwent a titanic eruption, driving gases and other material outward at 2 million miles per hour.

CONTAMINATION BY SUPERNOVAE IN GLOBULAR CLUSTERS

Credit: ALMA (ESO/NAOJ/NRAO)/Alexandra Angelich (NRAO/AUI/NSF) Only a small amount of the supernovae products remains trapped within globular clusters and this "catch" only occurs in the most massive cases (mass cluster ≥ 10^6 solar masses).

SUPER-EDDINGTON ACCRETION IN ACTIVE GALACTIC NUCLEI

Supermassive black holes at the cores of galaxies blast radiation and ultra-fast winds outward, as illustrated in this artist's conception. Credit: NASA/JPL-Caltech Broad emission lines are a hallmark feature of type 1 active galactic nuclei (AGNs) and quasars. Many basic properties of the broad-line region (BLR), such as its basic geometry, dynamics, and physical connection to the accretion disk around the supermassive black hole (BH), remain illdefined. AGN spectra exhibit both tremendous diversity as well as discernable patterns of systematic regularity.

SpaceTime

Search This Blog