Get your telescopes out in Spain... 2011 EY11

Asteroid 2011 EY11 to come closer to the Earth than the Moon!!!.....

The distance between the Earth and the Moon is: 384,401km

When measuring the distance between near earth objects, they use this distance as 1 LD.

Asteroid 2011 EY11 will come within 0.3 LD tonight according to Space Weather (scroll down the page)...somewhere between 75,000 km and 125,000 km

However it is only 9 km across!

"Scientists do not anticipate it to hit the planet."....

Just in case... I'm going to have a beer!

 Only 9km across? That´s huge!

9 meters - don't panic.

Sorry!

Typo!

9 m across... not 9 km!

Still.... this is very, very close!

I can't tell from the website, is this something we will see tonight or was it last night?

Justin

Today and tonight according to the Jet Propulsion Labs Small-body Database.... depending where on Earth you are!

Here is the Orbit Diagram from JPL for: 2011 EY11

For Western Europe it should be some time tonight!

There was another one, bigger but farther away overnight on the 26th Feb...

We were having a bbq that evening, and just after the sun disappeared, we saw an object travel across the sky, in an easterly direction.

It looked like it was right over Manilva from our viewpoint.

So, if you think you saw a UFO that night... it wasn't.... it was a Near Earth Object...

And if you look up tonight and think you see a UFO... then it's not, it's 2011 EY11

But say "Live long and prosper" just in case!

Will get the telescope out this evening.  It would be great to see it.

Thanks

Justin

This is set to be the closest NEO (Near Earth Object) to pass for some time.

Also, watch out for possible 'green fireballs' from tonight until the 9th March.

There are loads of NEO's every month, however most are quite far away in reality.

The one that is passing by tonight is special because it is within the lunar orbit - it will only be one third the distance between the Earth and the Moon.

Here's a table from JPL on NEO's during: March - June 2011

You will see form the table that there have already been 10 NEO's this month, and there will be another 80 during the next 4 months, including 2011 EY11

Every single NEO that has passed Earth this month, and over the next few months, will be 1 LD (distance of the Moon to Earth) or greater! .... except this one!

And by the way... 2011 EY11 was first discovered on the 5th May 2011

Hence why I'm saying.... this is close!

TechNo,

I suspect that you probably saw a UFO the other day (or more likely a satellite or the ISS) rather than one of the NEOs.

If the quoted magnitudes are correct on your link, there is no way any of these could be seen with the naked eye, or even with huge amateur telescopes.

Sky magnitudes are quoted on a reverse logarithmic scale, so the bigger the number, the fainter the star.  Really bright things have negative numbers.

As an example, the sun has a magnitude of around -27 whilst the full moon has a magnitude of about -13. Although this doesn't seem very different, because it's a log scale it shows that the sun is about 400,000 times brighter than the full moon.

The brightest star (Sirius) has a magnitude of about -1.5 and the maximum brightness of Saturn is around -0.5.

The faintest stars visible with the naked eye in an urban environment are around +3 to +4 magnitude and "down" to around +6.5 magnitude in excellent viewing conditions (you should be able to see around 10,000 stars in these conditions)

Uranus has a magnitude of around +5, although this tends to depend on how hot the curry was you ate on the previous night.

With a decent pair of binoculars, you can resolve down to magnitude +10, and with a 24" telescope (that's 24 inches wide !!) with a 30 minute exposure you could see magnitude 22 stars.

So, with magnitudes well into the 20s, it's unlikely that we'll ever see any NEOs with our naked eyes or even with half decent telescopes until they get VERY close, ie. in the earths atmosphere.

Still, it's still interesting to realise how busy our local space actually is.