Archive for the ‘Superlative’ Category

Superlative Chapter 2: The Fastest…

Thursday, July 31st, 2014

In the first edition of the Superlative series, we looked at the biggest things in the universe. Today we’ll explore another extreme – the fastest objects known.

Fastest Galaxy

The question of the fastest moving galaxy relative to us is not an easy one to answer. Because of the expanding universe, the speed at which distant galaxies are receding from our location is mostly due to the actual stretching of space. Thus, the further the galaxy from us, the further it is moving away from us.

Currently, the fastest known celestial object moving away from us is the primordial galaxy known as UDFy-38135539. It is also the furthest galaxy we have ever observed, at approximately 13.1 billion light years. This means UDFy-38135539 formed in the first 700 million years of the universe’s existence.

Infrared glow from the bow shock

Fastest Star

Recently, a number of new hypervelocity stars have been discovered in the Milky Way. These are stars that travel at more than two million miles per hour. The fastest of which is the star known as Kappa Cassiopeiae. It is traveling at 2.5 million miles an hour, and is at a distance of about 4000 light years from earth. Not to worry, Even if Kappa Cassiopeiae, which exists in the Cassiopeiae constellation, were heading directly for Earth, it still would take approximately 1.1 million years to reach our solar system.

Interestingly, hypervelocity stars such as Kappa Cassiopeiae impact the space in front of their direction of travel so much, that the interaction between the star’s magnetic field and the matter in space creates a large infrared glow. This phenomenon is known as a bow shock, and it can affect space up to four light years ahead of the star itself.

Artist’s rendition of VFTS 102

Fastest Rotating Object

The fastest rotating celestial body discovered to date does not exist in the Milky way, but rather a smaller galaxy approximately 160,000 light years away, known as the Large Magellanic Cloud. This star, known as VFTS 102, is about 25 times more massive than the sun, and was thought to be ejected from a binary star system. At its surface, it rotates at approximately 1 million miles an hour; about 100 times faster than our sun.

Fastest Planets

The fastest moving planet in our own solar system is Mercury. It has an orbital period (year) of just 88 Earth days, and moves through space relative to the sun at 107,700 mph. This is nearly double the 67,100 mph the Earth averages in it’s orbit around the sun.

As in most cases, exoplanets are far more extreme than our own solar system. Kepler 70b, for instance, has an orbital period of only 5.76 hours, giving it an orbital velocity of more than 375,000 mph.

Artist’s rendition of the Solar Probe Plus, set to launch in 2018

Fastest unmanned object

The current fastest man made object to exist was the Helios II probe launched on January 15th, 1976. It was put into orbit around the sun just inside the orbit of Mercury. At it’s nearest point (known as perihelion), it recorded a top speed of 157,078 miles per hour.

In the near future, the Juno probe which is set to visit Jupiter, will accelerate to 165,000 mph by using Earth’s gravity. Additionally, the Solar Probe Plus, set to launch in 2018, will take it on a similar mission as the Helios probe to study the sun. The probe is expected to reach speeds in excess of 450,000 mph, nearly three times the current record.

Fastest manned object

The fastest manned spacecraft, and thus the fastest humans have ever traveled relative to the Earth, was the Apollo 10 command module, on May 26th, 1969. This spacecraft was used for final testing in lunar orbit before Apollo 11 landed on the Moon. On its return flight home, it achieved a speed of 24,791 mph.

The Biggest in the Universe…

Saturday, November 23rd, 2013

Welcome to the first installment of the Vikings Astronomy Superlative Series. In the coming articles we will evaluate the most mind-blowing facts astronomy has to offer.

Galaxy

The largest galaxy observed in the universe is the ESO 146-IG 005 Galaxy. This galaxy was initially measured by the Gemini South Telescope in 2010, and exists approximately 1.4billion light years from Earth.  The ESO 146-IG 005 galaxy is about 30 trillion solar masses, which is 50 times larger than the Milky Way. It has been increasing its mass since the early stages of the universe by merging with smaller galaxies in its local group.

The most massive spiral galaxy is known as ISOHDFS 27. It is much further from Earth than ESO 146-IG 005, at approximately six billion light years. It is only about four times as large as the Milky Way.

Star

Our sun has a mass of about two nonillion kilograms, or 2,000,000,000,000,000,000,000,000,000,000kg. That’s about 1,300,000 times more massive than the earth. However the sun pales in comparison to the largest stars of our known universe.

NML Cygni is currently the largest known star, a red hypergiant roughly 25-40 times more massive than our sun. Its radius is even more impressive, approximately 1,650 times that of the sun. It is a part of the Milky Way, at about 5,300 light years from earth.

Ceres

Asteroid

The largest asteroid in the solar system is actually considered a dwarf planet. Ceres is 950km (590 mi) in diameter, and has a mass of 9.46×1020 kg. Ceres exists in the asteroid belt, which is an area of the solar system between mars and Jupiter. Ceres accounts for about one third of the entire mass of the asteroid belt. It was discovered on January 1st, 1801 by Guiseppe Piazzi, and was originally classified as a planet. The Dawn spacecraft is currently on its way to Ceres, and should arrive in 2015 to perform observations which will help scientists understand the early solar system. This will be the first time we’ve gotten an up close look at Ceres.

Exoplanet

As we learned in a recent article, there are hundreds of known planets outside of our solar system orbiting nearby stars. Because of the techniques used to find these planets, it is usually much easier to find large ones rather than small ones. Currently the largest confirmed exoplanet is CD-35 2722 b, which is approximately 31 times the size of Jupiter. Jupiter, for reference, has a mass of about 318 Earths. It was discovered in 2011.

Spacecraft

International Space Station

The largest manmade object that exists in space is the International Space Station (ISS). The ISS is a joint effort between multiple space agencies, and has been in space since 1998. It currently has a mass of about 990,000 lbs (450,000 kg). The space station has been slowly adding components since its launch, and may operate until 2028.

Saturn V Rocket During Launch

The largest (and most powerful) rocket ever to launch into space is the Saturn V rocket used by NASA during the late 60’s and early 70’s. It stood 363 feet tall, with a diameter of 33 feet, and weighed in at 6.2 million pounds. It was used during NASA’s Apollo program to launch spacecraft into Low Earth Orbit (LEO) as well as to the moon.