NuSTAR Update

Artist's concept of NuSTAR on orbit. Image Credit: NASA/JPL-Caltech

In anticipation of an upcoming launch, I recently provided an overview of NASA’s next on-orbit telescope, NuSTAR. At that time, the launch date had not yet been set. A news release was issued today, postponing the launch:

The planned launch of NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) mission has been postponed after a March 15 launch status meeting. The launch will be rescheduled to allow additional time to confirm the flight software used by the launch vehicle’s flight computer will issue commands to the rocket as intended.

The time required to complete the software review has moved NuSTAR beyond the March timeframe currently available on the range at Kwajalein. In the interim, NASA will coordinate with the launch site to determine the earliest possible launch opportunity. This is expected to be within the next two months.

(emphasis mine)

At this point, I’m not entirely sure what might have caused the delay. While NASA is calling it a postponement, they had never officially announced the launch date — though it was implied that it would be in March. In any case, I’d much rather them spend a couple of extra months increasing their confidence in a flawless launch and operations than face the potential consequences of hasty action.


NuSTAR

In just a few days (it looks like the launch date is March 21, but the date is “under review” as of this writing), the next NASA Small Explorer (SMEX) mission is set to launch. NuStar (Nuclear Spectroscopic Telescope Array) is the next orbital telescope that will collect high energy X-ray data and is the first on-orbit telescope to use a new generation of hard X-ray optics. Among its mission objectives are locating massive black holes, study the population of compact objects (such as collapsed stars and stellar mass black holes) located in the center of the Milky Way, create maps of of the material from young supernova remnants to better understand how stars explode and create elements, and discover what causes the relativistic jets that emanate from supermassive black holes.

Following a 1-month on-orbit checkout period, NuSTAR will begin its 2-year primary science mission; its main objectives taking an estimated 18 months (including the start-up month) with the six remaining months devoted to targeted observations, some of which will be determined after the mission has already begun. While the mission length is scheduled for two years, the telescope contains no consumables and can essentially function as long as it remains in orbit, which is in excess of five years. This extra time can be worked into extended missions working on Guest Observer proposals.

NuSTAR will work from an altitude of about 575 – 600 km (350 – 370 miles) in a low-earth orbit, inclined just 6° from the equator. This will allow it to have a view of about 80% of the sky at any given time.

The craft itself looks unlike any you’ve probably seen before. While it will launch in a stowed position, once in orbit the two main components will extend apart via a 10-meter mast, which will give the telescope a 10.15-meter focal length.

Artist's concept of NuSTAR

Artist's concept of NuSTAR on orbit. NuSTAR has a 10-m (30') mast that deploys after launch to separate the optics modules (right) from the detectors in the focal plane (left). The spacecraft, which controls NuSTAR's pointings, and the solar panels are with the focal plane. NuSTAR has two identical optics modules in order to increase sensitivity. Image Credit: NASA/JPL-Caltech

I can’t help but see some resemblance between NuSTAR and the “Satellite of Love” from Mystery Science Theatre 3000.

Satellite of Love from Mystery Science Theatre 3000

Satellite of Love from Mystery Science Theatre 3000

But I digress….

What’s also interesting to me about NuSTAR is the way it will be launched. Rather than a ground-based launch, the Pegasus XL rocket is carried up to 40,000 feet (12.19 kilometers) on the underside of a L-1011 Stargazer carrier aircraft, contracted through Orbital Sciences Corporation. Once dropped, it will fall for about five seconds before the rocket engines ignite, taking it up to an orbit altitude and trajectory.

Stay tuned for a successful launch of NuSTAR this month. I can’t wait to see the images it will produce and what mysteries it will unravel.