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A reddish speck photographed near a dim and distant star last year is indeed a planet, about five times the mass of Jupiter, an international team of astronomers is reporting today. They say the results bolster their claim, put forward last fall, that this image was the first of a planet orbiting a star outside the solar system. The planet, about 230 light-years from Earth in the constellation Hydra, orbits a kind of failed star known as a brown dwarf at a distance of at least five billion miles, twice as far as icy Neptune is from our own Sun....

Astronomers have directly observed an extrasolar planet for the first time, but are at a loss to explain what they see. More than 130 planets have been detected orbiting stars other than our own, the Sun. But because the stars far outshine the planets, all of the planets were detected indirectly - by how much they made their host stars wobble or dim, for example. Now, astronomers say they are almost certain they have snapped an actual image of an extrasolar planet. It was first seen at infrared wavelengths with the Very Large Telescope in Chile in April 2004, and...

The image is a composite. 2M1207b orbits the brown dwarf from almost twice as far as Neptune does from the sun, but in the image, the planet appears positioned close to its star. The data used to capture it comes from three near-infrared exposures in different wavebands. It's a technique used to produce images for public consumption, but more importantly, to locate exoplanets around stars. That's because infrared data lessens the huge brightness difference between a star and a planet, making the latter easier to find.It was produced using the 27-foot (8.2 meters) Yepun telescope — part of the Very...

The BA.2.75 variant is rising fast in the country, but hospitalization rates are low so far.As countries await the end of COVID-19 surges caused by the variant BA.5, researchers are on the lookout for what will come next. An Omicron subvariant called BA.2.75 — and nicknamed ‘Centaurus’ by some on social media — is rising fast in India. A few scientists are sounding the alarm, whereas others say it’s too early to tell whether the variant will spread widely. In India, it doesn’t yet seem to be driving up hospitalization or death rates. BA.2.75 has been detected in more than...

Explanation: The jets emanating from Centaurus A are over a million light years long. These jets of streaming plasma, expelled by a giant black hole in the center of this spiral galaxy, light up this composite image of Cen A. Exactly how the central black hole expels infalling matter remains unknown. After clearing the galaxy, however, the jets inflate large radio bubbles that likely glow for millions of years. If energized by a passing gas cloud, the radio bubbles can even light up again after billions of years. X-ray light is depicted in the featured composite image in blue, while...

In his book "2061 - Odyssey Three" (the third of his Space Odyssey series), Arthur C. Clarke put forward the intriguing proposal that the core of the planet Jupiter was, in fact, a diamond the size of Earth. Now Clarke, even though a science fiction author of some repute, had a science background and always tried to bring rigorous scientific accuracy to his stories. So, could his proposition be possible? The somewhat predictable answer is - we don't know. But we can analyse the possibility within known scientific parametres, to see if it is, at least, possible. For diamond to...

One month after its launch, NASA’s Transiting Exoplanet Survey Satellite has sent back an initial test image that shows more than 200,000 stars in the southern sky. TESS’ image was taken by one of its cameras with a two-second exposure. The picture is centered on the constellation Centaurus, with the edge of the dark Coalsack Nebula at upper right and the star Beta Centauri prominent along the lower edge. The picture provides only a hint of what TESS will be seeing once it starts delivering science-quality images next month. When all four wide-field cameras are in operation, TESS’ images...

Planet watchers have plenty to occupy themselves this month. Mars, being too close to the sun, is the only naked eye planet that is not observable. Jupiter will be the first “star” that becomes visible after sunset. It will be low in the southwest. It is so very bright that it can be seen in twilight, but how soon can you detect it? It can be fun to test just how early you can see it. The moon passes close to Jupiter on July 28 making for a pretty grouping. Saturn is up all night this month. It doesn’t get...

Explanation: This beautiful telephoto composition spans light-years in a natural night skyscape from the island of Crete. Looking south, exposures both track the stars and record a fixed foreground in three merged panels that cover a 10x12 degree wide field of view. The May 15 waxing gibbous moonlight illuminates the church and mountainous terrain. A mere 18 thousand light-years away, huge globular star cluster Omega Centauri (NGC 5139) shining above gives a good visual impression of its appearance in binoculars on that starry night. Active galaxy Centaurus A (NGC 5128) is near the top of the frame, some 11 million...

Explanation: Following an ancient galaxy-galaxy collision 200 million light-years from Earth, debris from a gas-rich galaxy, NGC 5291, was flung far into intergalactic space. NGC 5291 and the likely interloper, also known as the "Seashell" galaxy, are captured near the center of this spectacular scene. The sharp, ground-based telescopic image looks toward the galaxy cluster Abell 3574 in the southern constellation Centaurus. Stretched along the 100,000 light-year long tidal tails, are clumps resembling dwarf galaxies, but lacking old stars, apparently dominated by young stars and active star forming regions. Found to be unusually rich in elements heavier than hydrogen and...

If you live in the southern hemisphere, the southern sky constellation of Centaurus may look a little different to you tonight, as a bright nova has been identified in the region early this week. The initial discovery of Nova Centauri 2013 (Nova Cen 2013) was made by observer John Seach based out of Chatsworth Island in New South Wales Australia. The preliminary discovery magnitude for Nova Cen 2013 was magnitude +5.5, just above naked eye visibility from a good dark sky site. Estimates by observers over the past 24 hours place Nova Cen 2013 between magnitudes +4 and +5 “with...

A large asteroid visits our fair corner of the solar system this week, and with a little planning you may just be able to spot it. Near Earth Asteroid (NEA) 285263 (1998 QE2) will pass 6.2 million kilometres from the Earth on Friday, May 31st at 20:59 Universal Time (UT) or 4:59PM EDT. Discovered in 1998 during the LIncoln Near-Earth Asteroid Research (LINEAR) sky survey looking for such objects, 1998 QE2 will shine at magnitude +10 to +12 on closest approach. Estimates of its size vary from 1.3 to 2.9 kilometres, with observations by the Spitzer Space Telescope in 2010...

Explanation: Large spiral galaxy NGC 4945 is seen edge-on near the center of this cosmic galaxy portrait. In fact, NGC 4945 is almost the size of our own Milky Way Galaxy. Its own dusty disk, young blue star clusters, and pink star forming regions standout in the sharp, colorful telescopic image. About 13 million light-years distant toward the expansive southern constellation Centaurus, NGC 4945 is only about six times farther away than Andromeda, the nearest large spiral galaxy to the Milky Way. Though the galaxy's central region is largely hidden from view for optical telescopes, X-ray and infrared observations indicate...

Explanation: These are larger dust bunnies than you will find under your bed. Situated in rich star fields and glowing hydrogen gas, these opaque clouds of interstellar dust and gas are so large they might be able to form stars. Their home is known as IC 2944, a bright stellar nursery located about 5,900 light years away toward the constellation of Centaurus. The largest of these dark globules, first spotted by South African astronomer A. D. Thackeray in 1950, is likely two separate but overlapping clouds, each more than one light-year wide. Along with other data, the above representative color...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 August 6 Dusty Galaxy Centaurus A Credit: Marina Rejkuba (ESO-Garching) et al., ISAAC, VLT ANTU telescope, ESO Paranal Obs. Explanation: Why is peculiar galaxy Centaurus A so dusty? Dramatic dust lanes that run across the galaxy's center mark Cen A. These dust lanes are so thick they almost completely obscure the galaxy's center in visible light. This is particularly unusual as Cen A's red stars and round...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 July 5 Centaurus A: X-Rays from an Active Galaxy Credit: R.Kraft (SAO) et al., CXO, NASA Explanation: Its core hidden from optical view by a thick lane of dust, the giant elliptical galaxy Centaurus A was among the first objects observed by the orbiting Chandra X-ray Observatory. Astronomers were not disappointed, as Centaurus A's appearance in x-rays makes its classification as an active galaxy easy to appreciate....

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 May 1 The Energetic Jet from Centaurus A Credit: M. J. Hardcastle (Univ. Bristol), et al.X-ray; Chandra Observatory, NASA / Radio; NRAO, VLA Explanation: The center of well-studied active galaxy Centaurus A is hidden from the view of optical telescopes by a cosmic jumble of stars, gas, and dust. But both radio and x-ray telescopes can trace the remarkable jet of high-energy particles streaming from the galaxy's...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 April 19 Spiral Galaxy In Centaurus Credit: FORS1, VLT, ESO Explanation: Centaurus, the Centaur, is one of the most striking constellations in the southern sky. The lovely Milky Way flows through this large constellation whose celestial wonders also include the closest star to the sun, Alpha Centauri, the largest globular star cluster in our galaxy, Omega Centauri, and the closest active galaxy, Centaurus A. Embraced by tightly...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 March 17 SN 1006: History's Brightest Supernova Credit: Frank Winkler (Middlebury College et al., AURA, NOAO, NSF Explanation: Suddenly, in the year 1006 AD, a new star appeared in the sky. Over the course of just a few days, the rogue star became brighter than the planet Venus. The star, likely the talk of everyone who could see it, was recorded by people who lived in areas...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 February 20 Cold Wind from the Boomerang Nebula Credit: R. Sahai and J. Trauger (JPL), NASA/ESA Explanation: A cold wind blows from the central star of the Boomerang Nebula. Seen here in a detailed false-color image recorded in 1998 by the Hubble Space Telescope, the nebula lies about 5,000 light-years away towards the grand southern constellation of Centaurus. The symmetric cloud appears to have been created by...