In the Sky This Week – May 21, 2019

Jupiter’s Great Red Spot is Unraveling!

As I was writing this post, I came upon this story on SpaceWeather.com:

Around the world, amateur astronomers are monitoring a strange phenomenon on the verge of Jupiter’s Great Red Spot (GRS). The giant storm appears to be unraveling. “I haven’t seen this before in my 17-or-so years of imaging Jupiter,” reports veteran observer Anthony Wesley of Australia, who photographed a streamer of gas detaching itself from the GRS on May 19th –SpaceWeather.com

Jupiter, May 19, 2019. Credit: Anthony Wesley.

I realized I should probably headline this topic when I immediately stopped what I was doing, and went upstairs to tell my wife about it!

Jupiter returns the the evening sky, rising in the southeastern sky around 10:30 PM.

Jupiter rises in the southeastern sky around 10:30 PM this week; the location of dwarf planet Ceres is in the red cross hairs. Credit: Stellarium / Bob Trembley.

The Moon dances with Saturn and Jupiter for the next several days in the predawn sky:

Mars will soon be lost on the glare of the sunset in the west-northwestern sky.

Mars in the west-northwestern sky at dusk, May 21, 2019. Credit: Stellarium / Bob Trembley

Globular cluster Messier 68

“A ten billion year stellar dance.” Messier 68. Credit: ESA/Hubble & NASA

The NASA/ESA Hubble Space Telescope offers this delightful view of the crowded stellar encampment called Messier 68, a spherical, star-filled region of space known as a globular cluster. Mutual gravitational attraction amongst a cluster’s hundreds of thousands or even millions of stars keeps stellar members in check, allowing globular clusters to hang together for many billions of years.

Astronomers can measure the ages of globular clusters by looking at the light of their constituent stars. The chemical elements leave signatures in this light, and the starlight reveals that globular clusters’ stars typically contain fewer heavy elements, such as carbon, oxygen and iron, than stars like the Sun. Since successive generations of stars gradually create these elements through nuclear fusion, stars having fewer of them are relics of earlier epochs in the Universe. Indeed, the stars in globular clusters rank among the oldest on record, dating back more than 10 billion years.

More than 150 of these objects surround our Milky Way galaxy. On a galactic scale, globular clusters are indeed not all that big. In Messier 68’s case, its constituent stars span a volume of space with a diameter of little more than a hundred light-years. The disc of the Milky Way, on the other hand, extends over some 100 000 light-years or more.

Messier 68 is located about 33 000 light-years from Earth in the constellation Hydra (The Female Water Snake). French astronomer Charles Messier notched the object as the sixty-eighth entry in his famous catalogue in 1780.

Hubble added Messier 68 to its own impressive list of cosmic targets in this image using the Wide Field Camera of Hubble’s Advanced Camera for Surveys. The image, which combines visible and infrared light, has a field of view of approximately 3.4 by 3.4 arcminutes. – ESA/Hubble & NASA

Location of M68 May 21, 2019. Credit: Stellarium / Bob Trembley

I wondered what our Sun would look like as seen from Messier 68, so I went there in SpaceEngine and found out!

Artist view: near Messier 68 looking in the direction of the Sun (cross hairs). Credit: SpaceEngine / Bob Trembley.

The Moon is a waning gibbous, rising after sunset, visible high in the sky after midnight, and visible to the southwest after sunrise.

The third quarter Moon occurs on Sunday May 26^th; the Moon will rise around midnight, and visible to the south after sunrise.

The Moon from May 21-27, 2019. Visualizations by Ernie Wright / NASA’s Scientific Visualization Studio.

Moon News

The exciting sunspots from last week have rotated out of view, and the Sun has been spot-free for 2 days. Coronal holes appear at both poles, and a small hole appears between the south pole and the equator. SpaceWeather.com says: “Solar wind flowing from a weakly-organized hole in the sun’s atmosphere is expected to buffet Earth’s magnetic field this week. This will cause geomagnetic unrest, but probably not geomagnetic storms, on May 21st through 23rd. Photographic auroras mixed with moonlight are possible at high latitudes.”

Some exciting prominences on the limb of the Sun over the last few days!

The solar wind speed is 387.7 km/sec (↓), with a density of 3.3 protons/cm³ (↓).

Animated LASCO C2 Coronograph showing the solar corona above the Sun’s limb (the white circle). Credit: NASA/JPL-Caltech

Sun News

Upcoming Earth-asteroid encounters:

Notes: LD means “Lunar Distance.” 1 LD = 384,401 km, the distance between Earth and the Moon. Table from SpaceWeather.com

On May 20, 2019, the NASA All Sky Fireball Network reported 3 fireballs.
(3 sporadics)

In this diagram of the inner solar system, all of the fireball orbits intersect at a single point–Earth. The orbits are color-coded by velocity, from slow (red) to fast (blue). From: Spaceweather.com

Fireball News

https://twitter.com/LifeWithWeather/status/1130470272329506818

This is the position of the planets and a couple bodies in the solar system:

Solar System News – Jupiter’s Great Red Spot

OSIRIS-REx – Possible Sample Site in a Crater (left)

Juno – Exploring Jupiter’s Magnetic Field

Climate

You should have heard of this young woman by now:

Data from the NASA Exoplanet Archive

Exoplanet Artwork by Bob Trembley

Artist view of sunrise over super-hot, super-Jupiter exoplanet HD 220074 b. Credit: SpaceEngine / Bob Trembley.

LIGO Detects a Multiple Black Hole Mergers

Inexplicably, gravitational lensing has been on my mind for the last couple days; when the Muse strikes, go with it!

A gravitational lens is a distribution of matter (such as a cluster of galaxies) between a distant light source and an observer, that is capable of bending the light from the source as the light travels towards the observer. This effect is known as gravitational lensing, and the amount of bending is one of the predictions of Albert Einstein‘s general theory of relativity. (Classical physics also predicts the bending of light, but only half that predicted by general relativity.) – Wikipedia

Apps used for this post:

NASA Eyes on the Solar System: an immersive 3D solar system and space mission simulator – free for the PC /MAC.
I maintain the unofficial NASA Eyes Facebook page.
Stellarium: a free open source planetarium app for PC/MAC/Linux. It’s a great tool for planning observing sessions.
Universe Sandbox: a space simulator that merges real-time gravity, climate, collision, and material interactions to reveal the beauty of our universe and the fragility of our planet. Includes VR support.
Space Engine: a free 3D Universe Simulator for the PC. VR support coming soon!

Section header image credits:
The Sky – Stellarium/ Bob Trembley
Observing Target – Turn Left at Orion / M. Skirvin
The Moon – NASA/JPL-Caltech
The Sun – NASA/JPL-Caltech
Asteroids – NASA/JPL-Caltech
Fireballs – Credited to YouTube
Comets – Comet P/Halley, March 8, 1986, W. Liller
The Solar System – NASA Eyes on the Solar System / Bob Trembley
Spacecraft News – NASA Eyes on the Solar System / Bob Trembley
Exoplanets – Space Engine / Bob Trembley
The Universe – Universe Today

2018 is NASA’s 60th Anniversary!

July 20, 2019 is the 50^th Anniversary of the Apollo 11 landing on the Moon.