Astronomy Archives

April 24, 2019April 24, 2019 by Matt Williams

Astronomers Think a Meteor Came from Outside the Solar System

Multi-photo composite showing Perseid meteors shooting from their radiant point in the constellation Perseus. Earth crosses the orbit of comet 109P/Swift-Tuttle every year in mid-August. Debris left behind by the comet burns up as meteors when it strikes our upper atmosphere at 130,000 mph. Credit: NASA

When ‘Oumuamua was first detected on October 19th, 2017, astronomers were understandably confused about the nature of this strange object. Initially thought to be an interstellar comet, it was then designated as an interstellar asteroid. But when it picked up velocity as it departed our Solar System (a very comet-like thing to do), scientists could only scratch their heads and wonder.

After much consideration, Shmuel Bialy and Professor Abraham Loeb of the Harvard-Smithsonian Center for Astrophysics (CfA) proposed that ‘Oumuamua could in fact be an artificial object (possibly an alien probe). In a more recent study, Amir Siraj and Prof. Loeb identified another (and much smaller) potential interstellar object, which they claim could be regularly colliding with Earth.

April 24, 2019April 24, 2019 by Paul M. Sutter

Barfing Neutron Stars Reveal Their Inner Guts

Artist's illustration of two merging neutron stars. The narrow beams represent the gamma-ray burst while the rippling spacetime grid indicates the isotropic gravitational waves that characterize the merger. Swirling clouds of material ejected from the merging stars are a possible source of the light that was seen at lower energies. Credit: National Science Foundation/LIGO/Sonoma State University/A. Simonnet

We don’t really understand neutron stars. Oh, we know that they are – they’re the leftover remnants of some of the most massive stars in the universe – but revealing their inner workings is a little bit tricky, because the physics keeping them alive is only poorly understood.

But every once in a while two neutron stars smash together, and when they do they tend to blow up, spewing their quantum guts all over space. Depending on the internal structure and composition of the neutron stars, the “ejecta” (the polite scientific term for astronomical projectile vomit) will look different to us Earth-bound observers, giving us a gross but potentially powerful way to understand these exotic creatures.

April 23, 2019April 23, 2019 by Matt Williams

You Could Travel Through a Wormhole, but it’s Slower Than Going Through Space

Artist illustration of a spacecraft passing through a wormhole to a distant galaxy. Image credit: NASA.

Special Relativity. It’s been the bane of space explorers, futurists and science fiction authors since Albert Einstein first proposed it in 1905. For those of us who dream of humans one-day becoming an interstellar species, this scientific fact is like a wet blanket. Luckily, there are a few theoretical concepts that have been proposed that indicate that Faster-Than-Light (FTL) travel might still be possible someday.

A popular example is the idea of a wormhole: a speculative structure that links two distant points in space time that would enable interstellar space travel. Recently, a team of Ivy League scientists conducted a study that indicated how “traversable wormholes” could actually be a reality. The bad news is that their results indicate that these wormholes aren’t exactly shortcuts, and could be the cosmic equivalent of “taking the long way”!

April 19, 2019April 19, 2019 by Paul M. Sutter

What Will the James Webb Space Telescope See? A Whole Bunch of Dust, That’s What

With its helical appearance resembling a snail’s shell, this reflection nebula seems to spiral out from a luminous central star in this new NASA/ESA Hubble Space Telescope image. The star in the centre, known as V1331 Cyg and located in the dark cloud LDN 981 — or, more commonly, Lynds 981 — had previously been defined as a T Tauri star. A T Tauri is a young star — or Young Stellar Object — that is starting to contract to become a main sequence star similar to the Sun. What makes V1331Cyg special is the fact that we look almost exactly at one of its poles. Usually, the view of a young star is obscured by the dust from the circumstellar disc and the envelope that surround it. However, with V1331Cyg we are actually looking in the exact direction of a jet driven by the star that is clearing the dust and giving us this magnificent view. This view provides 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 verylow-mass object in the outer circumstellar disc.

When it comes to the first galaxies, the James Webb Space Telescope will attempt to understand the formation of those galaxies and their link to the underlying dark matter. In case you didn’t know, most of the matter in our universe is invisible (a.k.a. “dark”), but its gravity binds everything together, including galaxies. So by studying galaxies – and especially their formation – we can get some hints as to how dark matter works. At least, that’s the hope. It turns out that astronomy is a little bit more complicated than that, and one of the major things we have to deal with when studying these distant galaxies is dust. A lot of dust.

That’s right: good old-fashioned dust. And thanks to some fancy simulations, we’re beginning to clear up the picture.

April 19, 2019April 19, 2019 by Evan Gough

The First Molecule that was Possible in the Universe has been Seen in Space

Image of planetary nebula NGC 7027 with illustration of helium hydride molecules. In this planetary nebula, SOFIA detected helium hydride, a combination of helium (red) and hydrogen (blue), which was the first type of molecule to ever form in the early universe. This is the first time helium hydride has been found in the modern universe. Credits: NASA/ESA/Hubble Processing: Judy Schmidt

It takes a rich and diverse set of complex molecules for things like stars, galaxies, planets and lifeforms like us to exist. But before humans and all the complex molecules we’re made of could exist, there had to be that first primordial molecule that started a long chain of chemical events that led to everything you see around you today.

Though it’s been long theorized to exist, the lack of observational evidence for that molecule was problematic for scientists. Now they’ve found it and those scientists can rest easy. Their predictive theory wins!

April 18, 2019April 18, 2019 by Evan Gough

Methane-Filled Lakes on Titan are “Surprisingly Deep”

A near-infrared mosaic image of Saturn's moon Titan shows the sun reflecting and glinting off of Titan's northern polar seas. Image Credit: NASA/JPL-Caltech/University of Arizona/University of Idaho

The Cassini mission to Saturn and its moons wrapped up in 2017, when the spacecraft was sent plunging into the gas giant to meet its end. But there’s still a lot of data from the mission to keep scientists busy. A team of scientists working with Cassini data have made a surprising discovery: Titan’s methane-filled lakes are much deeper, and weirder, than expected.

April 18, 2019April 18, 2019 by Evan Gough

TESS Just Found its First Earth-Sized World

Artist's conception of HD 21749c, the first Earth-sized planet found by NASA's Transiting Exoplanets Survey Satellite (TESS), as well as its sibling, HD 21749b, a warm sub-Neptune-sized world. Credit: Robin Dienel/Carnegie Institution for Science.

NASA’s new planet-hunting telescope, TESS (Transiting Exoplanet Survey Satellite), just found its first Earth-sized world. Though the Earth-sized planet, and its hot sub-Neptune companion, were first observed by TESS in January 2019, it’s taken until now to confirm their status with ground-based follow-up observations. The discovery is published in The Astrophysical Journal Letters.

April 17, 2019April 17, 2019 by David Dickinson

Astro-Challenge: Spotting Slender Moons

Jimena Moon — A slender crescent Moon sighted from Jimena de la Frontera, Spain. Image Credit: Dave Dickinson

Up for a challenge? Some of the toughest targets for a backyard observer involve little or no equipment at all. Northern hemisphere Spring brings with it one of our favorite astronomical pursuits: the first sighting of the extremely thin, waxing crescent Moon. This unique feat of visual athletics may be fairly straight forward, requiring nothing more than a working pair of Mk-1 eyeballs… but it’s tougher than you think. The angle of the evening ecliptic in the Spring is still fairly high for mid-northern latitudes, taking the Moon up and out of the weeds when it reaches waxing crescent phase.

April 16, 2019February 17, 2020 by Matt Williams

Soviet/Russian Space Missions

Taken just after the flight of Voskhod 2 in 1965, in order of flight (from left), the first Soviet cosmonauts: Yuri Gagarin, Gherman Titov, Andrian Nikolayev, Pavel Popovich, Valeri Bykovsky, Valentina Tereshkova, Konstantin Feoktistov, Vladimir Komarov, Boris Yegorov, Pavel Belyayev and Alexei Leonov. Alexei had just returned to Earth after performing the first spacewalk in history during the Voskhod 2 mission. Credit: alldayru.com, via ESA.

In the history of spaceflight, only one nation has made contributions that rival or supersede those of the Soviet Union or Russia. While the Soviets are credited with making the historic firsts that launched the “Space Age“, the contributions made by Russian scientists predate this period considerably. In terms of theory, the history of Russian space exploration goes back to the 19th century.

However, as with the United States, the practice of sending missions to space did not begin until after World War II. It was at this time, during the fabled “Space Race” between the east and the west, that the Soviet Union conducted several pioneering missions in robotic and crewed spaceflight. These contributions have continued since the collapse of the Soviet Union in 1991, ensuring Russia’s continued role as a superpower in space.

April 16, 2019April 16, 2019 by Matt Williams

NASA Wants to Send a Low-Cost Mission to Explore Neptune’s Moon Triton

Global Color Mosaic of Triton, taken by Voyager 2 in 1989. Credit: NASA/JPL/USGS

In the coming years, NASA has some bold plans to build on the success of the New Horizons mission. Not only did this spacecraft make history by conducting the first-ever flyby of Pluto in 2015, it has since followed up on that by making the first encounter in history with a Kuiper Belt Object (KBO) – 2014 MU69 (aka. Ultima Thule).

Given the wealth of data and stunning images that resulted from these events (which NASA scientists are still processing), other similarly-ambitious missions to explore the outer Solar System are being considered. For example, there is the proposal for the Trident spacecraft, a Discovery-class mission that would reveal things about Neptune’s largest moon, Triton.