Comet Catalina and its closest approach to Earth

Over the past few years I’ve been interested in capturing images of comets as they move through the inner solar system. Some have been easier than others primarily because of their brightness but also because of where they lie in the sky.

Comet Catalina (C/2013 US10), however, has been a challenge. When it first became visible in the northern hemisphere it was difficult to see in the early morning twilight. Later, it moved so that it was well up in the sky before twilight but then I was fighting both bright moonlight and cloudy weather.

Finally, clear skies have allowed me another chance to take images of the comet this week. It is quickly moving through the northern skies towards the constellation Ursa Major and made its closest approach to Earth (at a very safe distance of 110 million km) last night (17 January 2016).

The comet isn’t bright enough to be visible to the unaided eye but binoculars are sufficient to reveal it as a fuzzy spot in the sky. With a DSLR and long exposure it’s possible to get reasonable images.

C/2013 US10 (Catalina) showing its double tail structure (12 January 2016).
C/2013 US10 (Catalina) showing its double tail structure (12 January 2016).
C/2013 US10 (Catalina) long exposure showing motion in the comet (12 January 2016).
C/2013 US10 (Catalina) long exposure showing motion in the comet (12 January 2016).
C/2013 US10 (Catalina) moving past stars in the Big Dipper handle and a couple of galaxies (12 January 2016).
C/2013 US10 (Catalina) moving past stars in the Big Dipper handle and a couple of galaxies (12 January 2016).

The first set of images are from 12 January 2016. The comet is approaching the handle of the Big Dipper. One long-exposure image shows points of light for stars but a short streak for the comet as it moves through the sky.

C/2013 US10 (Catalina) as it continues on its journey (18 January 2016).
C/2013 US10 (Catalina) as it continues on its journey (18 January 2016).

The second set of images are from 18 January 2016. Occasional clouds and a quarter moon made it more challenging to get a great image but there will be more opportunities later this month.

Another Space Station in the Sky

We all know about the International Space Station (ISS). Many people have watched as it flies overhead as a brilliant point of light moving across the sky.

But now it is no longer the only space station in the sky. On 29 September 2011 China launched its own space station known as Tiangong (“Heavenly Palace”). It’s not as bright as the ISS and thus less noticeable to most observers.

Tiangong and Shenzou spacecraft moving across the pre-dawn sky.
Tiangong and Shenzou spacecraft moving across the pre-dawn sky.

Then, on 01 November 2011, China launched the Shenzhou-8, an unmanned spacecraft designed to dock with Tiangong. And early on the morning of 02 November 2011, both spacecraft passed overhead cutting through the constellation Orion. Just a few hours later, Shenzou-8 successfully docked with Tiangong.

The dual spacecraft flyby is reminiscent of the ISS-Shuttle flybys.

The final flight of the Endeavour

As the Endeavour (STS-134) mission comes to an end NASA is one step closer to the final chapter of the Space Shuttle program. The Discovery has already flown its final mission. The upcoming flight of Atlantis will be the final and last shuttle mission.

ISS and STS-134 along with frozen cloud of ice particles from a vented tank over northern Arizona.
ISS and STS-134 along with frozen cloud of ice particles from a vented tank over northern Arizona.

Endeavour undocked from the International Space Station (ISS) at 8:55 pm MST 29 May 2011 (0355 UTC 30 May 2011) and began a slow separation from the ISS in preparation for its landing on Wednesday. The double flyby of the ISS and the STS-134 Endeavour over northern Arizona early this morning resulted in this spectacular image as the two spacecraft emerged from Earth’s shadow. In preparation for its return to Earth Endeavour had vented its tanks creating an ice cloud in space that was moving along with the two craft.

This is a composite of eight images of 15 seconds duration. There is a small gap between each image as the camera shutter briefly closed. Also visible in this image in the upper right is the faint track of another earth orbiting satellite — most likely COSMOS 2228 Nova 1.

Edit: Received information that the satellite is Nova1.

The final flight of the Discovery

An era has come to an end as the NASA space shuttle Discovery landed earlier this week after a successful mission to the International Space Station (ISS). This was the last flight for Discovery and it will now be retired to a museum.

After Discovery undocked from the ISS their orbits began to separate with the shuttle flying across the sky a few tens of seconds earlier than the ISS. On the night before returning to Kennedy Space Center, the ISS and Discovery made two evening twilight passes across the southwestern United States.

ISS and STS-133 transiting the northern sky above the San Francisco Peaks.
ISS and STS-133 transiting the northern sky above the San Francisco Peaks.

The first pass came early in the evening with a still bright twilight sky. The ISS and Discovery only rose to about 17 degrees above the horizon and this made it easy to capture an image with the San Francisco Peaks and the Kachina wetlands in the same photograph.

ISS and STS-133 climbing out of the western sky and entering the Earths shadow as they approach the lunar disk.
ISS and STS-133 climbing out of the western sky and entering the Earths shadow as they approach the lunar disk.

About 95 minutes later a second pass occurred. This time the two spacecraft arose from the western sky and climbed higher towards the crescent moon before disappearing into the Earths shadow.

Only two more shuttle missions remain and then, truly, it will be the end of an era.