An M80 with No Kaboom

M80This one’s a star cluster not a firecracker.

M80 is in the constellation Scorpius between the stars α Scorpii (Antares) and β Scorpii in a part of the Milky Way rich in nebulae. When viewed with a modest amateur telescope (like mine), it appears as a mottled ball of light. This Hubble image shows more detail. M80 is roughly 95 light-years in diameter. It contains several hundred thousand stars, making it one of the more densely populated globular clusters in the galaxy.

M80 contains a fair number of blue stragglers, stars that appear to be much younger than the cluster itself. Astronomers believe that these stars lost part of their outer layers during close encounters with other cluster members or as the result of collisions between stars in the tightly packed cluster. Images from Hubble show regions with very high blue straggler densities which suggests that the center of the cluster probably has a very high capture and collision rate.

Image Credit: NASA

A Helicopter on Mars

Nighttime temperatures at Jezero Crater on Mars can drop to -90 C which can damage unprotected electrical components and ruin batteries. However, the Ingenuity helicopter survived its first night after being deployed from the Perseverance rover on 3 April. If all goes well, Ingenuity will be the first aircraft to attempt powered, controlled flight on another planet.

Image Credit: NASA

The Veil Nebula

The Veil Nebula is about 2,100 light-years from Earth in the constellation of Cygnus (the Swan), making it a relatively close neighbor in astronomical terms. It’s the visible portion of a supernova remnant formed around 10,000 years ago known as the Cygnus Loop.

This image which only shows a portion of the nebula. It was assembled from data taken using five different filters with the Wide Field Camera 3 on the Hubble Space Telescope. Post-processing of the data brings out enhanced details of emissions from doubly ionized oxygen (blues) and ionized hydrogen and ionized nitrogen (reds).

Image Credit: NASA / ESA / Z. Levay

Just Passing By—For Now

Asteroid 99942 Apophis made a relatively distant pass by Earth on 5 March. It will be back. This animation shows the trajectory of  the asteroid as it flies safely past Earth on 13 April, 2029. Earth’s gravity will slightly deflect the trajectory as the 340-meter-wide Near-Earth Object comes within 32,000 kilometers of the Earth’s surface. The motion has been sped up by a factor of 2,000. Recent observations and refined calculations show that 99942 Apophis should not hit the Earth for at least a century.

Video Credit: NASA / JPL

Supernova Leftovers

About 11,000 years ago, a star went supernova. The light from this event first reached Earth around A.D. 1667. There are no records of anyone noticing probably because large amounts of dust between the dying star and Earth obscured our view of the explosion.

The remnants of this supernova was finally noticed in 1947 by radio astronomers. Now known as Cassiopeia A, it is one of the brightest radio sources in the whole sky. More recently, the Wide-field Infrared Survey Explorer (WISE) was used to observe the infrared echoes from the supernova.

When WISE took this image, the blast wave had expanded out to about a distance of 21 light-years, but he flash of light from the explosion, traveling at the speed of light, had covered well over 300 light-years. The orange-colored echoes further out from the central remnant have been reflected from interstellar dust that was heated by the supernova flash centuries after the original explosion.

Image Credit: NASA / JPL / UCLA

Dactyl

The asteroid Ida orbits the Sun between the orbits of Mars and Jupiter. It takes about 4.8 years to complete an orbit. Ida has a moon named Dactyl, official designation (243) Ida I Dactyl, discovered in images taken by the Galileo spacecraft during its flyby in 1993. These images provided the first direct confirmation of an asteroid moon. Dactyl is heavily cratered, like Ida, and consists of similar materials, suggesting they are fragments of the same parent body. Ida is the dot on the right side of the image above. The image on the left is our best closeup of Dactyl to date. Dactyl is about 1.6 x 1.4 x 1.2 km across.

Image Credits: NASA

A Young Stellar Object

A young star takes centre stageThe reflection nebula spiraling out of this star looks a bit like a snail’s shell.The star V1331 Cyg is located in a dark cloud and is classified as a Young Stellar Object, but it is starting to contract to become a main sequence star similar to the Sun.

From our point of view V1331Cyg is special because we look almost exactly at one of its poles. Usually, the view of a young star is obscured by the dust from its circumstellar disc. In the case of V1331Cyg we are looking straight into the polar jet driven by the star that is clearing the dust. This point of view give us an almost undisturbed view of the star and its immediate surroundings, allowing astronomers to study it in greater detail and look for features that might suggest the formation of a very low-mass object (a planet) in the outer circumstellar disk.

Image Credit: ESA / NASA

An Irregular Dwarf Galaxy

ngc-4214This is dwarf galaxy NGC 4214 which is forming clusters of new stars from its interstellar gas and dust. The young clusters of new stars are within glowing gas clouds. The gas glows because it is excited by the strong ultraviolet light emitted from the young stars forming in the gravitational collapse of the gas. These hot stars eject stellar winds moving at thousands of km/s which blow bubbles in the gas. Near the center of the galaxy, there is a cluster of hundreds of massive blue stars, each more than 10,000 X brighter than our Sun, and a huge bubble inflated by stellar winds and radiation pressure surrounds the cluster.

Image Credit: NASA / ESA

Warp Factor

How did spiral galaxy ESO 510-13 get bent out of shape? The disks of many spiral galaxies are thin and flat, but with the gaps between star they are not solid. Spiral disks are loose conglomerations of billions of stars and diffuse gas all gravitationally orbiting a galaxy center. The common flat disk shape  is thought to be created by sticky collisions of large gas clouds early in the galaxy’s formation. Warped disks are not uncommon, though, and even our own Milky Way Galaxy is thought to have a bit of warp. The causes of spiral warps are still being investigated, but some warps are thought to result from interactions or even collisions between galaxies. ESO 510-13, shown in the digitally sharpened Hubble image above, is about 150 million light years away and about 100,000 light years across.

Image Credit: NASA

An Eye in Space?

Sauron in SpaceEven though it looks like it belongs atop the Dark Tower of Barad-dûr, this fiery swirl is actually a planetary nebula known as ESO 456-67. It lies in the constellation of Sagittarius (The Archer) in the southern sky.

It is possible to see in this image of the nebula the various layers of material expelled by the central star. Each appears in a different color—red, orange, yellow, and green-tinted bands of gas are visible, with clear patches of at the center. Astronomers don’t fully understood how planetary nebulae form such a wide variety of shapes and structures. Some are spherical, some elliptical, others shoot material in waves from their polar regions, some look like hourglasses or figures of eight, and others resemble large, messy stellar explosions.

Image Credit: NASA