Astronomy Archives

October 1, 2022October 1, 2022 by Matt Williams

NASA's Dragonfly Helicopter Will be Exploring This Region of Titan

Cassini radar image of the Selk Crater, the landing site for the upcoming Dragonfly mission. Credit: NASA/JPL-Caltech/ASI/Cornell

In June 2027, NASA will launch the long-awaited Dragonfly mission toward Saturn’s largest moon, Titan. By 2034, the 450 kg (990-lbs) nuclear-powered quadcopter will touch down at its target landing site (the Selk crater region) and begin searching Titan’s surface and atmosphere to learn more about this curious satellite. In particular, the mission will investigate the moon’s prebiotic chemistry, active methane cycle, and organic environment. These goals underpin Dragonfly’s main objective, which is to search for possible signs of life (aka. “biosignatures”) on Titan.

For years, scientists have speculated if life could exist on Titan since it appears to possess all the necessary ingredients (though not for life as we know it). This curiosity has only deepened since the Cassini–Huygens mission, which spent thirteen years exploring Saturn and its system of moons (from 2004 and 2017). Recently, a team of Cornell researchers combined and analyzed radar images taken by Cassini to determine the properties of the surface. The result is a detailed map of the Dragonfly‘s landing site, revealing a landscape of sand dunes and broken-up icy ground.

September 30, 2022September 30, 2022 by Allen Versfeld

Stars Spiral Inward to the Cores of Stellar Nurseries

Image of NGC 346, a stellar nursery where astronomers have discovered newborn stars spiralling in towards the center of a nebula — Astronomers have been bemused to find young stars spiralling into the centre of a massive cluster of stars in the Small Magellanic Cloud, a satellite galaxy of the Milky Way. The outer arm of the spiral in this huge, oddly shaped stellar nursery — called NGC 346 — may be feeding star formation in a river-like motion of gas and stars. This is an efficient way to fuel star birth, researchers say.

Astronomers studying a stellar cluster within the Small Magellanic Cloud (SMC) have found young stars spiraling in towards the center of the cluster. The cluster, NGC 346, is an open cluster embedded within a glowing cloud of gas, which is typical of stellar nurseries – places where new stars are formed. The outer spiral arm of this star forming region appears to be funneling gas, dust and new stars into the center, which researchers describe as an efficient way to fuel the birth of new stars.

September 29, 2022September 30, 2022 by Alan Boyle

Mysterious Europa Gets an Extreme Closeup From NASA’s Juno Probe

Juno's view of Europa — The ridges and troughs on Europa stand out in an image from NASA's Juno orbiter. (NASA / JPL-Caltech / SwRI / MSSS / Björn Jónsson)

Over the course of a brief two-hour opportunity, NASA’s Juno spacecraft captured a rare close look at Europa, an ice-covered moon of Jupiter that’s thought to harbor a hidden ocean — and perhaps an extraterrestrial strain of marine life.

Juno has been orbiting Jupiter since 2016, but this week brought the best opportunity to look at Europa, which is the prime target for investigation by NASA’s Europa Clipper probe in the 2030s. On Sept. 29, the orbiter buzzed over the moon’s surface at a velocity in excess of 52,000 mph (23.6 km per second), and at an altitude of 352 kilometers (219 miles).

That’s as close as any spacecraft has come to Europa since the Galileo orbiter’s 218-mile flyby in 2000.

September 29, 2022September 30, 2022 by Cathrine Versfeld

China uses drag sail to clear up space junk successfully.

Scientists at the Shanghai Academy of Spaceflight Technology (SAST) have devised an ingenious way to combat the growing problem of space debris. The team fitted a drag sail to a Long March 2 rocket and successfully launched it in July this year. Rocket launches often leave discarded booster stages in low-earth orbit, adding to the pollution of near-earth space. The pilot testing for the sail came as a surprise to many space agencies when, a day after the rocket’s launch, the 25 square meters deorbiting sail was unfolded.

September 28, 2022September 28, 2022 by Brian Koberlein

Jupiter’s Atmosphere is Surprisingly Hot

Temperature measurements of Jupiter's upper atmosphere. Credit: James O’Donoghue

Jupiter is a big planet, but it’s still a planet. That means it doesn’t heat itself through fancy mechanisms like nuclear fusion. Its interior is heated through its own weight, squeezing the interior through hydrostatic equilibrium, and its surface is heated mostly by the Sun. Since Jupiter only gets about 4% of the light per square meter that Earth gets, you’d expect its upper atmosphere to be pretty cold. Traditional models estimate it should be about -70 degrees Celsius. But recent measurements show the upper atmosphere is over 400 degrees Celsius, and in the polar regions as much as 700 degrees Celsius. In the words of Ruby Rhod from the movie The Fifth Element, “It’s Hot Hot Hot!”

September 28, 2022September 28, 2022 by Matt Williams

A Fascinating Look at Jupiter's Clouds Where the Light Intensity is Converted Into 3D

A still image from the 3D animation that shows the elevation of Jupiter's cloud tops. Credit: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt

In July 2016, NASA’s Juno space probe reached Jupiter, becoming the second spacecraft in history to orbit the gas giant (the first being the Galileo probe that orbited Jupiter from 1995 to 2003). The data it has sent back has led to new revelations about the Jovian atmosphere, magnetosphere, gravitational field, structure, and composition. While its primary mission was intended to only last until 2018, a mission extension means that Juno will continue to orbit Jupiter’s poles (a perijove maneuver) and send back stunning images and data until 2025.

Recently, a team of citizen scientists led by mathematician and software developer Gerald Eichstädt used images taken by the probe’s visible-light camera/telescope (the JunoCam) to create a 3D animation of Jupiter’s upper atmosphere. Eichstädt’s animation was presented at the 2022 Europlanet Science Congress (EPSC), which took place from September 18 – 23 in Granada, and shows the relative heights of the cloud tops of Jupiter that reveal delicately textured swirls and peaks. Eichstädt’s work also showcased the potential for citizen science and public engagement with today’s missions.

September 27, 2022September 27, 2022 by Carolyn Collins Petersen

Another Ghostly Spiral Galaxy Revealed by JWST

JWST and IC 5332 — This image of the spiral galaxy IC 5332, taken by the NASA/ESA/CSA JWST observatory, with its MIRI instrument. Courtesy ESA/Webb, NASA & CSA, J. Lee and the PHANGS-JWST and PHANGS-HST Teams

The famous American baseball player once said, “You can observe a lot just by watching.” That’s certainly true of the JWST, which just released its latest “spider-web” image of a distant galaxy. It “watched” IC 5332 using the onboard Mid-InfraRed Instrument (MIRI). In the process it observed spectacular details not easily seen in visible light.

September 27, 2022September 27, 2022 by Carolyn Collins Petersen

Climate Change is Making the Skies Worse for Astronomy

climate change could affect observatories like these on Mauna Kea in Hawaii. — The top of Mauna Kea is a prime site for telescopes, as shown in this image. It boasts clear, dry atmospheric conditions. Global climate change could alter that. Image courtesy Mauna Kea Observatories

Light pollution. Satellite trains and radio frequency interference. Encroaching civilization. These all pose threats to ground-based astronomy. But, did anyone ever think that global climate change might wreak havoc on observatories? It turns out the answer is “yes.”

September 27, 2022September 27, 2022 by Matt Williams

TESS Finds a Super-Earth and two Mini-Neptunes in a Single System

An artist’s rendition of the Transiting Exoplanet Survey Satellite (TESS). Credit: NASA's Goddard Space Flight Center

The field of extrasolar planet studies continues to grow by leaps and bounds. Currently, 5,090 exoplanets have been confirmed in 3,816 systems, and another 8,933 candidates are awaiting confirmation. The majority of these have been Neptune-like gas giants (1,779), gas giants comparable to Jupiter or Saturn (1,536), and rocky planets many times the size of Earth (1,582). The most effective means for finding exoplanets has been the Transit Method (aka. Transit Photometry), where periodic dips in a star’s brightness are seen as an indication of a planet passing in front of its star (transiting) relative to the observer.

Using data from NASA’s Transiting Exoplanet Survey Satellite (TESS), an international team of astronomers has discovered a three-planet system orbiting a Sun-like star (HD 22946, or TOI 11) located about 205.5 light-years. Based on size estimates yielded from their transits, the team theorizes that these exoplanets consist of a rocky planet several times the size of Earth (a Super-Earth) and two gas giants smaller than Neptune. Given its proximity, this system could be ideal for follow-up studies and characterization with the James Webb Space Telescope (JWST).

September 26, 2022September 26, 2022 by David Dickinson

Jupiter at Opposition 2022, Closest in 59 Years

Be sure to observe Jupiter this week, during its finest apparition of a lifetime.

You’ve never seen Jove like this. Jupiter opposition season for 2022 is upon us tonight, as the King of the Planet shines rising in the east opposite to the setting Sun in the west. This is the very best time to catch Jupiter and its retinue of moons, as they dominate the sky throughout the night. And although Jupiter reaches opposition as seen from the Earth nearly every year, this one is special as it’s the closest to the Earth in our lifetimes, and the nearest for the 21^st century.