Space and astronomy news
A 16-year-old high school girl who is attempting to sail solo around the world spotted a bright bolide over the Pacific Ocean during the peak of last week’s Leonid meteor shower. The International Meteor organization relies on reports just like this from observers in the field….or in this case “all at sea”.
Jessica Watson a student from Queensland, Australia, has set off on the adventure of a lifetime, attempting to become the youngest woman to sail solo and unassisted around the world.
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Five of the planets are visible with the unaided eye and have been known about for thousands of years. Uranus was discovered in 1781, and Neptune was found in 1846. but when was Pluto discovered?
Pluto was discovered February 18th, 1930 by Clyde Tombaugh at the Lowell Observatory in Flagstaff, Arizona. Now that Uranus and Neptune had been discovered, astronomers were certain that there were more planets in the outer Solar System. The director of the Lowell Observatory, Vesto Melvin Slipher, handed the job of finding this next planet, dubbed “Planet X” to the 23-year old Tombaugh.
Tombaugh used a tool called a “blink comparator” to compare two photographs of the night sky. He worked methodically, comparing two photographic plates, looking for any object that jumped from one night to another night. And finally on February 18th, 1930, Tombaugh discovered Pluto; a faint object in the right orbit.
The name for Pluto was chosen by an 11-year old British school girl named Venetia Burney. This continued the tradition of naming planets after Roman gods. Pluto was the Roman god of the underworld, the same as Hades in Greek mythology. It also matched the first initials of Percival Lowell, who the observatory was named after. Lowell died in 1916, and so he never saw the discovery of Pluto.
We have written many articles about the discovery of planets in the Solar System for Universe Today. Here’s an article about when Uranus was discovered, and here’s an article about when Neptune was discovered.
If you’d like more info on Pluto, check out Hubblesite’s News Releases about Pluto, and here’s a link to NASA’s Solar System Exploration Guide to Pluto.
We’ve also recorded a couple of episodes of Astronomy Cast about Pluto. Here’s a good one, Episode 64: Pluto and the Icy Outer Solar System.
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Were you wondering when was Jupiter discovered? Well, there’s no way to know. Jupiter is one of the 5 planets visible with the unaided eye. If you go outside and Jupiter is up in the sky, it’s probably the brightest object up there, brighter than any star; only Venus is brighter. So the ancient people have known about Jupiter for thousands of years, and there’s no way to know when the first person noticed the planet.
Perhaps a better question to ask is, when did we realize that Jupiter was a planet? In ancient times, astronomers used to think that the Earth was the center of the Universe. This was the geocentric model. The Sun, the Moon, the planets, and even the stars all orbited around the Earth in a series of crystal shells. But one thing that was hard to explain was the strange movements of the planets. They would move in one direction, then stop and go backwards in a retrograde motion. Astronomers created ever more elaborate models to explain these bizarre movements.
But then in the 1500s Nicolaus Copernicus developed his model of a Sun-centered, or heliospheric model of the Solar System. The Sun was center of the Solar System, and the planets, including Earth and Jupiter orbited around it. This nicely explained the strange movements of the planets in the sky. They were really following a circular path around the Sun, but the Earth was also traveling around the Sun, and this created different speeds based on our perspective.
The first person to actually view Jupiter in a telescope was Galileo. Even with his rudimentary telescope, he was able to see bands across the planet, and the 4 large Galilean moons that have been named after him. The moons clearly were orbiting Jupiter, which broke the theory that everything in the Universe was orbiting the Earth.
With bigger telescopes, astronomers were able to see more details in Jupiter’s cloud tops and discover more moons. But it wasn’t until the space age that scientists got to really study Jupiter close up. NASA’s Pioneer 10 was the first spacecraft to fly past Jupiter in 1973. It passed within 34,000 km of the cloud tops.
We’ve written several articles about when the planets of the Solar System were discovered. Here’s an article about the discovery of Uranus, and here’s an article about the discovery of Neptune.
If you’d like more information on Jupiter, check out Hubblesite’s News Releases about Jupiter, and here’s a link to NASA’s Solar System Exploration Guide to Jupiter.
We’ve also recorded an entire episode of Astronomy Cast just about Jupiter. Listen here, Episode 56: Jupiter.
Reference:
NASA
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Were you wondering who discovered Saturn? Well, nobody knows. Here’s the problem. Saturn is one of the 5 planets that you can see with the unaided eye. In fact, if you’re seeing a bright star in the sky, there’s a good chance it’s Saturn. It takes a telescope to see the rings, but anybody can find Saturn, even in a bright city.
So perhaps a better question might be to ask, when did astronomers realize that Saturn was a planet? The ancient astronomers believed in the geocentric model of the Universe. The Earth was at the center of the Universe, and everything else orbited around it in crystal shells: the Sun, the Moon, the planets and the stars. One problem with this model was the strange movements of the planets. They would sometimes slow down, stop and even travel backwards in the sky. And to explain this, astronomers had to create elaborate models for the planets where the orbited inside spheres within spheres.
Anyway, this model was turned on its ear by Nicolaus Copernicus in the 1500s. He placed the Sun at the center of the Solar System, and had all the planets orbiting around it. This nicely explained the strange movements of the planets. They weren’t going backwards, it was just a change in perspective, since the Earth is also going around the Sun.
The first person to actually look at Saturn in a telescope was Galileo. He saw a strange oval-shaped planet. He thought the planet might have ears, or two small balls on either side. Later observations showed that these were actually Saturn’s grand ring system. Galileo also discovered Saturn’s moon Titan.
Better observations of Saturn by Giovanni Cassini turned up 4 additional moons of Saturn, as well a division in the rings that would later be named after him: the Cassini division.
But it wouldn’t be until 1979 that the first spacecraft flew past Saturn. NASA’s Pioneer 11 spacecraft made the journey, getting within 20,000 km of the planet’s cloud tops. This was followed by the Voyager spacecraft, and eventually NASA’s Cassini spacecraft that’s orbiting the planet today. All of our best images of Saturn were sent back by orbiting spacecraft.
We have written many articles about the discovery of planets for Universe Today. Here’s an article about the discovery of Uranus, and here’s an article about the discovery of Neptune.
If you’d like more info on Saturn, start with the NASA Cassini mission homepage. That’s where you’ll see all the latest news and photos sent back from Saturn. Then check out Hubblesite’s News Releases about Saturn.
We’ve also recorded an entire episode of Astronomy Cast just about Saturn. Check it out here, Episode 59: Saturn.
Reference:
NASA
You might know the name “Hubble” because of the Hubble Space Telescope. But this phenomenal observatory was named after one of the most influential astronomers in modern history. Hubble discovered that galaxies are speeding away from us in all directions, leading to our current understanding of an expanding Universe. Let’s learn about the man behind the telescope.
Click here to download the episode.
Or subscribe to: astronomycast.com/podcast.xml with your podcatching software.
Launching a rocket into space requires a big effort on the ground. Space agencies have built up huge infrastructures to store, prepare and launch rockets. Let’s take a look at what’s involved on the ground at a place like Cape Canaveral. What happens before, during and after a launch.
Click here to download the episode.
Or subscribe to: astronomycast.com/podcast.xml with your podcatching software.
Were you wondering when was Venus discovered? Actually, there’s no way to know. Venus is one of the 5 planets visible with the unaided eye. In fact, Venus is the brightest object in the night sky after the Sun and the Moon. When Venus is at its brightest, it even casts shadows. So even ancient people would have been aware of Venus, and so there’s no way to know who that first person was, and when it happened.
However, a better question might be to ask, when did we know that Venus was a planet? This happened about the same time that astronomers first realized the Earth was a planet too. In ancient times, astronomers used to think that the Earth was the center of the Universe, and everything orbited around it: the Sun, the Moon, the planets and the stars. One problem with this model was the strange behavior of the planets. Sometimes they would speed up, and then slow down, stop, and even go backwards in the sky.
But then in the 1500s, Nicolaus Copernicus developed his model of a Sun-centered Solar System. The Earth was just a planet, and all of the planets orbited around the Sun instead. This model explained how the planets could have such strange movements. Since the Earth is moving too, we’re really just seeing them from different perspective in they sky.
The first person to see Venus in a telescope was Galileo. Although he wasn’t able to resolve anything but a bright disk (astronomers can’t do any better today), he saw that Venus went through phases like the Moon. This was further evidence that Venus orbits around the Sun – closer than the Earth, and so we see it in various phases of illumination.
Because Venus is shrouded in clouds, astronomers weren’t able to get a better view of Venus until the first spacecraft arrived from Earth. The first spacecraft to visit Venus was NASA’s Mariner 2, which arrived at Venus in 1962. But even then the planet was still blocked by clouds. The Russian Venera landers were able to pierce through the clouds and landed on the surface to send back a few quick images of the planet’s surface. They showed a hellish world, with thick atmosphere, clogging clouds, and blasting heat, hot enough to melt lead. NASA’s Magellan spacecraft (launched in 1989) was equipped with a radar instrument that allowed it to pierce through the clouds on Venus and show the planet’s landscape, craters and volcanoes.
We’ve written many articles about the discovery of planets for Universe Today. Here’s an article about the discovery of Uranus, and here’s an article about the discovery of Neptune.
If you’d like more information on Venus, check out Hubblesite’s News Releases about Venus, and here’s a link to NASA’s Solar System Exploration Guide on Venus.
We’ve also recorded an entire episode of Astronomy Cast about Venus. Listen here, Episode 50: Venus.
Pluto is incredibly faint. You need a powerful backyard telescope to even see it as a dot, so it’s not surprising that Pluto wasn’t discovered until the modern age. Who discovered Pluto? That was the astronomer Clyde Tombaugh, who found Pluto on February 18, 1930.
Tombaugh worked as an astronomer at the Lowell Observatory in Flagstaff, Arizona. He was given the task of finding a trans-Neptunian object which was predicted by Percival Lowell and William Pickering – the search for Planet X. Tombaugh used a tool called a blink comparator to study two images of the same region of the sky taken several nights apart. He would display one image and then blink to the second image to see if any objects had moved from night to night.
And so on February 18, 1930, Tombaugh turned up just such an object moving at the right speed to be the unknown Planet X. The name “Pluto” was suggested by Venetia Burney, and 11-year old English school girl. Pluto was the name of the Roman god of the underworld, and Percival Lowell liked it because the first two letters started with PL, after his own initials.
Pluto was considered the 9th planet in the Solar System until 2006, when the International Astronomical Union reclassified Pluto as a dwarf planet, joining Eris and Ceres as the Solar System’s 3 dwarf planets. There are now only 8 planets in the Solar System.
We have written many articles about the discovery of planets in the Solar System. Here’s an article about who discovered Uranus, and here’s an article about who discovered Neptune.
If you’d like more info on Pluto, check out Hubblesite’s News Releases about Pluto, and here’s a link to NASA’s Solar System Exploration Guide to Pluto.
We’ve also recorded several episodes of Astronomy Cast about Pluto. Start here, Episode 64: Pluto and the Icy Outer Solar System.
K. Itagaki of Yamagata, Japan was photographing the night sky in Eridanus two days ago when Hitoshi Yamaoka of Kyushu University noticed an anomaly – a possible classic nova event. Just how big a jump in amplitude did this star make? Try at least seven magnitudes within hours… and Joe Brimacombe was on it.
According to AAVSO Special Notice #181 released on November 25, 2009, there could be a possible nova in Eridanus. “Central Bureau Electronic Telegram No. 2050 (Daniel W. E. Green, Ed.) announces the discovery of a possible nova in Eridanus, as reported by Hitoshi Yamaoka, Kyushu University, by K. Itagaki, Yamagata, Japan, at magnitude 8.1 on images taken Nov. 25.536 UT. The object was confirmed by Itagaki on an image taken on Nov. 25.545.
Coordinates: R.A. = 04:47:54.21 Decl. = -10:10:43.1 (equinox 2000.0)
According to CBET No. 2050, “Itagaki notes that there is a faint (mag about 15) object near this position on his archival patrol images. Yamaoka suggests that it might be the brightening of a 15th-mag blue star that is contained in many catalogs (USNO-B1.0 position end figures 54s.19, 42″.9), noting that the amplitude of seven magnitudes is rather large for a dwarf nova, but somewhat small for a rapid classical nova. Yamaoka adds that the ASAS-3 system (Pojmanski 2002, Acta. Astron. 52, 397) also detected this object at the following V magnitudes: Nov. 10.236 UT, [14.0:; 19.241, 7.34; 22.179, 7.98; 24.269, 8.12.” Finder charts for this object may be plotted using VSP by entering the coordinates into the form at the this URL.
This object has been assigned the VSX identifier VSX J044754.2-101043. An AUID will be assigned by the VSX moderators and will be added to the on-line version of this notice when it becomes available. Please report observations to the AAVSO International Database as N ERI 2009 or VSX J044754.2-101043.”
Within 24 hours even more news came in via AAVSO Special Notice #182:
“This new variable object in Eridanus, originally called a possible nova in CBET 2050, is most likely a WZ Sge variable. It matches closely the coordinates of GSC1.2 05325-01837, listed in that catalog at 14.76 mag. At the peak outburst magnitude of 7.3, this is about 7.5 magnitudes amplitude, within the range of a galactic variable and lower than a typical nova. It appears to be fading and is about V=8.5 right now. However, WZ Sge cataclysmic variables have a complex light curve and the star may re-brighten. We are awaiting spectral
confirmation and possible GCVS naming, and will pass on that information as soon as possible.
As mentioned in Special Notice 181, the star has been entered as VSX J044754.2-101043 and now has an AUID of 000-BJR-847. You can submit observations to the AAVSO with either identifier. We have a preliminary sequence from Mati Morel, and have obtained BVRI imagery using the Bright Star Monitor at Astrokolkhoz Observatory
which we will use to construct a multiwavelength sequence tomorrow (November 27).
This is a good target for time series photometry, and at its current brightness, we highly recommend using filters. Larger telescopes should consider B or even U filters.”
Congratulations to K. Itagaki on his latest discovery, to AAVSO for pinning it down and to Joe Brimacombe for his quick imaging of the phenomena!
Mars is one of the 5 planets visible with the unaided eye. On any dark night, when Mars is in the sky, it’s easy to see with your own eyes. Ancient people knew about Mars, and long ago discovered that it moves from night to night compared to the stars. So it’s impossible to know who discovered Mars. That would have been one of the first humans.
Perhaps a better question to ask is: who realized that Mars is a planet? And that discovery happened with the idea that the Earth is a planet.
In ancient times, astronomers thought that the Earth was the center of the Universe, and the Sun, Moon, planets and stars orbited around us in a set of crystalline spheres. But the motions of the planets were hard to explain; they would sometimes speed up, stop, and even reverse their direction in the sky.
But the astronomer Nicolaus Copernicus developed the view that it was the Sun that was at the center of the Solar System, and the planets orbited around it. This view neatly explained the strange motions of the planets, since the Earth was also moving around the Sun, and these quirks were really just changes in perception.
Galileo was the first person to view Mars in a telescope, and he saw not much more than a bright disk. He did take many observations over the course of the year and realized that Mars gets closer and more distant, and so larger and smaller in his telescope. As telescopes got bigger and better, astronomers were able to make out the polar ice caps on Mars, and some astronomers incorrectly thought they saw a system of canals crisscrossing the surface of the planet.
But the best views of Mars came with the first robotic exploration of Mars. The first spacecraft to arrive at Mars was NASA’s Mariner 4, launched in 1964. The first spacecraft to go into orbit around Mars was Mariner 9, in 1971. These spacecraft helped take high resolution images that revealed craters, mountains and chasms; the red landscape of Mars that we’re so familiar with today.
We’ve written many articles about the discovery of planets for Universe Today. Here’s an article about the discovery of Uranus, and another about the discovery of Neptune.
If you’d like more information on Mars, check out Hubblesite’s News Releases about Mars, and here’s a link to the NASA Mars Exploration home page.
We’ve also recorded several episodes of Astronomy Cast about Mars. Start here, Episode 52: Mars.
References:
NASA Mars Exploration
NASA: The Mariner Missions