Archive for the ‘Astronomy’ Category

There’s a new paper coming out in Astronomy and Astrophysics from Wu, Usoskin et al that is of interest to us. It reconstructs solar activity over 9 millennia. When I get a copy of the data, I’ll compare it to Steinhilber et al’s 2012 effort.



A montage of Uranus’ large moons and one smaller moon: from left to right Puck, Miranda, Ariel, Umbriel, Titania and Oberon. Size proportions are correct. [image credit: Vzb83 @ Wikipedia (from originals taken by NASA’s Voyager 2)]

The five major moons of Uranus in ascending distance from the planet are:
Miranda, Ariel, Umbriel, Titania and Oberon

Of these, the first three exhibit a synodic resonance similar to that of Jupiter’s Galilean moons, as we showed here:
Why Phi? – the resonance of Jupiter’s Galilean moons

Quoting from that post:
The only exact ratio is between the synodic periods which is 3:2:1.
It isn’t necessary to have an exact 4:2:1 orbit ratio in order to get a 3:2:1 synodic ratio.


Astronomer announces he has discovered … Mars

Posted: March 22, 2018 by oldbrew in Astronomy, humour

Mars [image credit: NASA]

As banana skins go, this is a good one. Bad luck, professor!

In an online publication, this astronomer reports the detection of a very bright object in the night sky that wasn’t there before. Turns out, he’s thousands of years late for this discovery, says LiveScience.

Astronomer Peter Dunsby just made a groundbreaking discovery, after noticing a very bright “star” pop up in his field of view at an observatory at the University of Cape Town that was not present two weeks prior.

Too bad Dunsby was perhaps thousands of years late … the bright object was the planet Mars.


NASA releases stunning photo of cartwheel galaxy

Posted: January 24, 2018 by oldbrew in Astronomy

It’s an enhancement of an earlier image, but this just has to be seen.
H/T Sci-News

NASA has released the sharpest image ever taken of the Cartwheel Galaxy, a lenticular galaxy in the constellation Sculptor.

The Cartwheel Galaxy was first spotted on wide-field images from the U.K. Schmidt telescope and then studied in detail using the Anglo-Australian Telescope.

Also known as LEDA 2248, ESO 350-40 and IRAS 00352-3359, the galaxy is an estimated 150,000 light-years in diameter and has a mass of about 3 billion solar masses.

Along with the two galaxies on the left, the Cartwheel is part of a group of galaxies approximately 500 million light-years away.

According to astronomers, the cartwheel shape of the galaxy is the result of a violent galactic collision.

Continued here.

K2-138 could even have more than five planets. [image credit: NASA/JPL-Caltech]

And it’s a good one. The abstract says: ‘The periods of the five planets are 2.35, 3.56, 5.40, 8.26, and 12.76 days, forming an unbroken chain of near 3:2 resonances.’

The Exoplanet Explorers project has led to the first discovery of a multi-planet system solely through crowdsourcing efforts, as Futurism reports.

Through a project called Exoplanet Explorers, a band of citizen scientists has discovered K2-138, a far-off planetary system that houses least five exoplanets.

This is the first time that a multi-planet system has been discovered entirely through crowdsourcing.


Star system has record eight exoplanets

Posted: December 14, 2017 by oldbrew in Astronomy, Astrophysics, News
Tags: ,

Kepler Space Telescope [credit: NASA]

The two nearest planets to the star Kepler-90 (90b and 90c) are very close to a 5:4 (i.e. first order) orbit ratio.

Nasa finds a distant star circled by eight planets, equal to the complement in our own Solar System, BBC News reports.

It’s the largest number of worlds ever discovered in a planetary system outside our own.

The star known as Kepler-90, is just a bit hotter and larger than the Sun; astronomers already knew of seven planets around it.

The newly discovered world is small enough to be rocky, according to scientists.


A/2017 U1 may be from beyond our solar system [image credit: Tony873004 / Wikipedia]

This is real, unlike the object in the 1980s spoof ‘It Came From Somewhere Else’, described by one critic as ‘filmed on a shoestring budget, without the shoe and without the string’ – but amusing anyway. “We have been waiting for this day for decades,” said one scientist.

A small, recently discovered asteroid – or perhaps a comet – appears to have originated from outside the solar system, coming from somewhere else in our galaxy, says If so, it would be the first “interstellar object” to be observed and confirmed by astronomers.

This unusual object – for now designated A/2017 U1 – is less than a quarter-mile (400 meters) in diameter and is moving remarkably fast.

Astronomers are urgently working to point telescopes around the world and in space at this notable object. Once these data are obtained and analyzed, astronomers may know more about the origin and possibly the composition of the object.


Saturn’s moon Janus

Cassini maintains its reputation for surprises right to the end. It’s the ‘moon resonances’ that maintain ring stability, but with a new twist.

For three decades, astronomers thought that only Saturn’s moon Janus confined the planet’s A ring – the largest and farthest of the visible rings.

But after poring over NASA’s Cassini mission data, Cornell astronomers now conclude that the teamwork of seven moons keeps this ring corralled, as explains.

Without forces to hold the A ring in check, the ring would keep spreading out and ultimately disappear.


Star KIC 8462852 in infrared (2MASS survey) and ultraviolet (GALEX) [credit: NASA]

One observer commented about “Tabby’s Star” that ‘every explanation that doesn’t involve aliens has some sort of problem’. Its nickname is the WTF star, reports

Round 5 a.m. on a Tuesday this past May, Tabetha “Tabby” Boyajian sat staring at a laptop, cross-legged on her couch in the living room of her Baton Rouge, La., home. The coffee table was cluttered with the artifacts of an all-nighter: an empty wine glass to calm her nerves alongside an empty coffee mug to fuel her through the night.

Since midnight, Boyajian had been downloading and analyzing data from the Las Cumbres telescopes—two on Maui, Hawaii, and two more on the Spanish island of Tenerife off the coast of West Africa—that sat trained on an F-type star, bigger and hotter than the sun, near the constellation Cygnus.


Mercury [image credit: NASA]

The first photos of ice at Mercury’s poles were released in 2014 but this research goes a step further, as reports. It finds that ‘the total area of the three sheets [is] about 3,400 square kilometers—slightly larger than the state of Rhode Island’.

The scorching hot surface of Mercury seems like an unlikely place to find ice, but research over the past three decades has suggested that water is frozen on the first rock from the sun, hidden away on crater floors that are permanently shadowed from the sun’s blistering rays.

Now, a new study led by Brown University researchers suggests that there could be much more ice on Mercury’s surface than previously thought.

The study, published in Geophysical Research Letters, adds three new members to the list of craters near Mercury’s north pole that appear to harbor large surface ice deposits.


Where is Planet 9? [credit: NASA]

This may say something about what is not likely to be true about the mysterious, or mythical, Planet 9 but obviously it’s still all in the realms of theory. If it did form around the sun, how did it get to be so much further away from it than the known major planets in the solar system?

Astronomers at the University of Sheffield have shown that ‘Planet 9’ – an unseen planet on the edge of our solar system – probably formed closer to home than previously thought, reports

A team led by Dr Richard Parker from the University of Sheffield’s Department of Physics and Astronomy has found that Planet 9 is ‘unlikely’ to have been captured from another planetary system, as has previously been suggested, and must have formed around the sun.

The outskirts of the solar system have always been something of an enigma, with astronomers in the late 19th and early 20th centuries searching for a giant planet that wasn’t there, and the subsequent discovery of Pluto in 1930.


Showing all of the Moon including the side we never see from Earth. Composite from images taken by the Lunar Orbiter


Much media attention on this new paper this week. Is there a surprise lurking in the details now that the orbit period of the seventh planet has been confirmed?.

What the numbers in the diagram show is the orbits per planet in a fixed period (top row), the conjunctions per planet pair in the same period (second row), and the ratios that represents (third row).

The number of conjunctions of any two planets is the difference between the two orbit numbers in a given period, which in this case is equivalent to just under 1446 Earth days (see data below).

Apart from the obvious symmetry of the ratios, something else arose from the science paper.


Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, the largest astronomical project in the world –
Magellanic Clouds near top of image [credit: NASA / Ames]

It’s unimaginably vast: astronomers say ‘this structure is a 75,000 light-year long filament of gas and dust’. Trying to separate out the effects of gravity and magnetism here should be an interesting challenge.

A magnetic field appears to span the space between the Large and Small Magellanic Clouds, the two dwarf galaxies being consumed by our Milky Way Galaxy, reports Sky & Telescope via

For stargazers in the Northern Hemisphere, it’s easy to forget that the Milky Way is actively consuming two dwarf galaxies. Those in the Southern Hemisphere have a front row seat to watch our galaxy wreak havoc on the Large and Small Magellanic Clouds (LMC and SMC).

But there’s more to the story — the dwarfs are not only gravitationally interacting with the Milky Way but with each other as well.


The Lined Wolf

Let’s face it: KIC 8462852 (also Tabby’s Star or Boyajian’s Star) is a weird star. Since its unusual light variations were discovered by citizen scientists using data of NASA’s Kepler space telescope in September 2015 many, many things have been written by professional and amateur astronomers, science communicators and “searchers of mysteries”, as an interesting hypothesis about its behavior was that it could be signs of activity associated with intelligent extraterrestrial life constructing a Dyson swarm. Of course, this just run wild in general media, and many astronomers since them have been asked by journalist to talk about “Mysterious Tabby’s Star”.

In particular, this theme soon captured the attention of some of my friends at the Instituto de Astrofísica de Canarias (IAC, Spain), as they weekly produce an amazing ~2h science communication podcast Coffee Break: Señal y Ruido (Signal to noise). I’m proud to participate in this podcast from…

View original post 547 more words

Astrophysicist Ian Wilson has emailed me to ask for a brainstorming session at the talkshop to assist him. Ian writes:

“I was wondering if you or your colleagues (e.g. oldbrew) could help me work out the solution to the following lunar puzzle”


The Conundrum

The diagram below shows the Perigee of the lunar orbit pointing at the Sun at 0.0 days. In addition, the diagram shows the Perigee of the lunar orbit once again pointing at the Sun after one Full Moon Cycle (FMC) = 411.78443025 days. It takes more than 1.0 sidereal year (= 365.256363004 days) for the Perigee to realign with the Sun because of the slow pro-grade (clockwise) precession of the lunar line-of-apse once every 8.85023717 sidereal years.

1.0 FMC falls short of 15 anomalistic months (= 413.31824817 days) by 1.53381792 days (= 1.5117449198O). During these 1.5117449198 days the Perigee end of the lunar line-of-apse rotates by 0.17081406in a prograde direction, producing an overall movement of the line-of-apse (red line) of 1.34093086O (= 1.5117449198O – 0.17081406O) with respect to the Earth-Sun line (blue line).


The 1,100 year orbit of ‘DeeDee’

The solar system’s dwarf-planet population is about to increase by one, reports The far-flung object 2014 UZ224 — informally known as DeeDee, for “Distant Dwarf” — is about 395 miles wide (635 kilometers), new observations reveal.

That means the frigid object probably harbors enough mass to be shaped into a sphere by its own gravity, entitling it to “dwarf planet” status, researchers said.

Astronomers first spotted DeeDee in 2014 using the optical Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile (though they didn’t announce the discovery until 2016).

Size comparison of GJ 1132 b (aka Gliese 1132 b) with Earth [credit: Wikipedia]

Early indications from models suggest that ‘an atmosphere rich in water and methane would explain the observations very well.’

Astronomers have detected an atmosphere around the super-Earth GJ 1132b, reports the Max Planck Institute for Astronomy.

This marks the first detection of an atmosphere around a low-mass Super-Earth, in terms of radius and mass the most Earth-like planet around which an atmosphere has yet been detected.

Thus, this is a significant step on the path towards the detection of life on an exoplanet. The team, which includes researchers from the Max Planck Institute for Astronomy, used the 2.2 m ESO/MPG telescope in Chile to take images of the planet’s host star GJ 1132, and measuring the slight decrease in brightness as the planet and its atmosphere absorbed some of the starlight while passing directly in front of their host star.

While it’s not the detection of life on another planet, it’s an important step in the right direction: the detection of an atmosphere around the super-Earth GJ 1132b marks the first time an atmosphere has been detected around a planet with a mass and radius close to that of Earth (1.6 Earth masses, and 1.4 Earth radii).

The largest ‘TNOs’

This is about the ‘no-name’ dwarf planet 2007 OR10, which has the unusual property of being 3 times further from the Sun at aphelion (furthest) than at perihelion (nearest).

Everybody gets a moon! With the discovery of a small moon orbiting the third-largest dwarf planet, all the large objects that orbit beyond Neptune now have satellites, reports New Scientist.

Trans-Neptunian objects (TNOs) spend most or all of their orbits beyond Neptune. Last April, the dwarf planet Makemake became the ninth of the ten TNOs with diameters near or above 1,000 kilometres known to have a moon.

So when dwarf planet 2007 OR10 was found to be rotating more slowly than expected, it was suspected that a moon might be the culprit.