A Binary Asteroid


This time-lapse video was put together from Hubble Space Telescope photos. It shows two asteroids with comet-like features orbiting each other. The asteroid pair, called 2006 VW139/288P, was observed in 2016, just before its closest approach to the Sun. The photos reveal the binary system has a tail like a comet. The apparent movement of the tail is caused by changes in the relative alignment between the Sun, Earth, and 2006 VW139/288P between observations. The tail orientation is also affected by a change in the particle size. The pair was emitting relatively large particles (about 1 mm) in late July, and the tail was pointing in more or less the same direction as most of the particle emissions. However, after 20 September, 2016, the tail began to point in the opposite direction as pressure of sunlight pushed smaller (about 10 µm) dust particles away from the Sun.

Credits: NASA, ESA, and J. DePasquale and Z. Levay (STScI)

The Heart of the Crab


Here’s NASA’s description of this video—

This video starts with a composite image of the Crab Nebula, a supernova remnant that was assembled by combining data from five telescopes spanning nearly the entire breadth of the electromagnetic spectrum: the Very Large Array, the Spitzer Space Telescope, the Hubble Space Telescope, the XMM-Newton Observatory, and the Chandra X-ray Observatory.

The video dissolves to the red-colored radio-light view that shows how a neutron star’s fierce “wind” of charged particles from the central neutron star energized the nebula, causing it to emit the radio waves. The yellow-colored infrared image includes the glow of dust particles absorbing ultraviolet and visible light. The green-colored Hubble visible-light image offers a very sharp view of hot filamentary structures that permeate this nebula. The blue-colored ultraviolet image and the purple-colored X-ray image shows the effect of an energetic cloud of electrons driven by a rapidly rotating neutron star at the center of the nebula.

Video Credit: NASA, ESA, J. DePasquale (STScI)

NGC 3370


IDL TIFF fileSpiral galaxy NGC 3370 is roughly the same size and general layout as our Milky Way. It’s about 100 million light-years away in the direction of the constellation Leo. It dominates the foreground of this Hubble image (click it to embiggen) which shows other galaxies scattered in the background. This particular picture is detailed enough for study of individual pulsating stars known as Cepheid variables that can be used to accurately determine the distance to the galaxy. NGC 3370 is also home to a recent type Ia supernova. Combining the known distance to this “standard candle” supernova and the Cepheid data with observations of other supernovae at even greater distances has been useful in refining estimates of the age and expansion rate of the Universe.

Image Credit: NASA

A Star Is Born


Actually, a whole lot of them. This massive, young stellar grouping, called R136, is only a few million years old and resides in the 30 Doradus (aka Tarantula) Nebula, a turbulent star-birthing region in the Large Magellanic Cloud, a satellite galaxy of our Milky Way. There is no known star-forming region in our galaxy as large or as prolific as 30 Doradus.

Many of the diamond-like icy blue stars are among the most massive stars known. Some are 100 times more massive than our sun. These huge stars are destined to explode like a string of firecrackers when they become supernovas in a few million years.

This picture, taken in ultraviolet, visible, and red light by Hubble’s Wide Field Camera 3, spans about 100 light-years. The nebula is close enough to Earth that Hubble can resolve individual stars, giving astronomers important information about the stars’ birth and evolution.

The brilliant stars are carving deep cavities in the surrounding material by unleashing a torrent of ultraviolet light, and strong stellar winds (streams of charged particles), which scour away the enveloping hydrogen gas cloud in which the stars were born. The image shows a  what looks like a landscape of pillars, ridges, and valleys, as well as a dark region in the center that looks a bit like the outline of a Christmas tree. In addition to sculpting the gaseous “terrain,” these brilliant stars are also helping create a new generation of offspring. When the stellar winds hit dense walls of gas, they create shock waves which can create a new wave of star birth.

This picture was put together from observations taken in October, 2009. The blue color is light from the hottest, most massive stars; the green from the glow of oxygen; the red from fluorescing hydrogen.

Image Credit: NASA